In sel_make_bools, kernel allocates memory for bool_pending_names[i]
with security_get_bools. So if we just free bool_pending_names, those
memories for bool_pending_names[i] will be leaked.
This patch resolves dozens of following kmemleak report after resuming
from suspend:
unreferenced object 0xffff88022e4c7380 (size 32):
comm "init", pid 1, jiffies 4294677173
backtrace:
[<ffffffff810f76b5>] create_object+0x1a2/0x2a9
[<ffffffff810f78bb>] kmemleak_alloc+0x26/0x4b
[<ffffffff810ef3eb>] __kmalloc+0x18f/0x1b8
[<ffffffff811cd511>] security_get_bools+0xd7/0x16f
[<ffffffff811c48c0>] sel_write_load+0x12e/0x62b
[<ffffffff810f9a39>] vfs_write+0xae/0x10b
[<ffffffff810f9b56>] sys_write+0x4a/0x6e
[<ffffffff81011b82>] system_call_fastpath+0x16/0x1b
[<ffffffffffffffff>] 0xffffffffffffffff
Signed-off-by: Xiaotian Feng <dfeng@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Right now the syslog "type" action are just raw numbers which makes
the source difficult to follow. This patch replaces the raw numbers
with defined constants for some level of sanity.
Signed-off-by: Kees Cook <kees.cook@canonical.com>
Acked-by: John Johansen <john.johansen@canonical.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
This allows the LSM to distinguish between syslog functions originating
from /proc/kmsg access and direct syscalls. By default, the commoncaps
will now no longer require CAP_SYS_ADMIN to read an opened /proc/kmsg
file descriptor. For example the kernel syslog reader can now drop
privileges after opening /proc/kmsg, instead of staying privileged with
CAP_SYS_ADMIN. MAC systems that implement security_syslog have unchanged
behavior.
Signed-off-by: Kees Cook <kees.cook@canonical.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <jmorris@namei.org>
Allow runtime switching between different policy types (e.g. from a MLS/MCS
policy to a non-MLS/non-MCS policy or viceversa).
Signed-off-by: Guido Trentalancia <guido@trentalancia.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Always load the initial SIDs, even in the case of a policy
reload and not just at the initial policy load. This comes
particularly handy after the introduction of a recent
patch for enabling runtime switching between different
policy types, although this patch is in theory independent
from that feature.
Signed-off-by: Guido Trentalancia <guido@trentalancia.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
This patch removes dead code in type_attribute_bounds_av().
Due to the historical reason, the type boundary feature is delivered
from hierarchical types in libsepol, it has supported boundary features
both of subject type (domain; in most cases) and target type.
However, we don't have any actual use cases in bounded target types,
and it tended to make conceptual confusion.
So, this patch removes the dead code to apply boundary checks on the
target types. I makes clear the TYPEBOUNDS restricts privileges of
a certain domain bounded to any other domain.
Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
--
security/selinux/ss/services.c | 43 +++------------------------------------
1 files changed, 4 insertions(+), 39 deletions(-)
Signed-off-by: James Morris <jmorris@namei.org>
Per https://bugzilla.redhat.com/show_bug.cgi?id=548145
there are sufficient range transition rules in modern (Fedora) policy to
make mls_compute_sid a significant factor on the shmem file setup path
due to the length of the range_tr list. Replace the simple range_tr
list with a hashtab inside the security server to help mitigate this
problem.
Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
If allow_unknown==deny, SELinux treats an undefined kernel security
class as an error condition rather than as a typical permission denial
and thus does not allow permissions on undefined classes even when in
permissive mode. Change the SELinux logic so that this case is handled
as a typical permission denial, subject to the usual permissive mode and
permissive domain handling.
Also drop the 'requested' argument from security_compute_av() and
helpers as it is a legacy of the original security server interface and
is unused.
Changes:
- Handle permissive domains consistently by moving up the test for a
permissive domain.
- Make security_compute_av_user() consistent with security_compute_av();
the only difference now is that security_compute_av() performs mapping
between the kernel-private class and permission indices and the policy
values. In the userspace case, this mapping is handled by libselinux.
- Moved avd_init inside the policy lock.
Based in part on a patch by Paul Moore <paul.moore@hp.com>.
Reported-by: Andrew Worsley <amworsley@gmail.com>
Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
Don't pass current RLIMIT_RTTIME to update_rlimit_cpu() in
selinux_bprm_committing_creds, since update_rlimit_cpu expects
RLIMIT_CPU limit.
Use proper rlim[RLIMIT_CPU].rlim_cur instead to fix that.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Eric Paris <eparis@parisplace.org>
Cc: David Howells <dhowells@redhat.com>
The last return is unreachable, remove the 'return'
in default, let it fall through.
Signed-off-by: WANG Cong <amwang@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
The size argument to kcalloc should be the size of desired structure,
not the pointer to it.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@expression@
expression *x;
@@
x =
<+...
-sizeof(x)
+sizeof(*x)
...+>// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Historically we've seen cases where permissions are requested for classes
where they do not exist. In particular we have seen CIFS forget to set
i_mode to indicate it is a directory so when we later check something like
remove_name we have problems since it wasn't defined in tclass file. This
used to result in a avc which included the permission 0x2000 or something.
Currently the kernel will deny the operations (good thing) but will not
print ANY information (bad thing). First the auditdeny field is no
extended to include unknown permissions. After that is fixed the logic in
avc_dump_query to output this information isn't right since it will remove
the permission from the av and print the phrase "<NULL>". This takes us
back to the behavior before the classmap rewrite.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
For SELinux to do better filtering in userspace we send the name of the
module along with the AVC denial when a program is denied module_request.
Example output:
type=SYSCALL msg=audit(11/03/2009 10:59:43.510:9) : arch=x86_64 syscall=write success=yes exit=2 a0=3 a1=7fc28c0d56c0 a2=2 a3=7fffca0d7440 items=0 ppid=1727 pid=1729 auid=unset uid=root gid=root euid=root suid=root fsuid=root egid=root sgid=root fsgid=root tty=(none) ses=unset comm=rpc.nfsd exe=/usr/sbin/rpc.nfsd subj=system_u:system_r:nfsd_t:s0 key=(null)
type=AVC msg=audit(11/03/2009 10:59:43.510:9) : avc: denied { module_request } for pid=1729 comm=rpc.nfsd kmod="net-pf-10" scontext=system_u:system_r:nfsd_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=system
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
The SELinux dynamic class work in c6d3aaa4e3
creates a number of dynamic header files and scripts. Add .gitignore files
so git doesn't complain about these.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Ensure that we release the policy read lock on all exit paths from
security_compute_av.
Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Drop remapping of netlink classes and bypass of permission checking
based on netlink message type for policy version < 18. This removes
compatibility code introduced when the original single netlink
security class used for all netlink sockets was split into
finer-grained netlink classes based on netlink protocol and when
permission checking was added based on netlink message type in Linux
2.6.8. The only known distribution that shipped with SELinux and
policy < 18 was Fedora Core 2, which was EOL'd on 2005-04-11.
Given that the remapping code was never updated to address the
addition of newer netlink classes, that the corresponding userland
support was dropped in 2005, and that the assumptions made by the
remapping code about the fixed ordering among netlink classes in the
policy may be violated in the future due to the dynamic class/perm
discovery support, we should drop this compatibility code now.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Add a simple utility (scripts/selinux/genheaders) and invoke it to
generate the kernel-private class and permission indices in flask.h
and av_permissions.h automatically during the kernel build from the
security class mapping definitions in classmap.h. Adding new kernel
classes and permissions can then be done just by adding them to classmap.h.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Modify SELinux to dynamically discover class and permission values
upon policy load, based on the dynamic object class/perm discovery
logic from libselinux. A mapping is created between kernel-private
class and permission indices used outside the security server and the
policy values used within the security server.
The mappings are only applied upon kernel-internal computations;
similar mappings for the private indices of userspace object managers
is handled on a per-object manager basis by the userspace AVC. The
interfaces for compute_av and transition_sid are split for kernel
vs. userspace; the userspace functions are distinguished by a _user
suffix.
The kernel-private class indices are no longer tied to the policy
values and thus do not need to skip indices for userspace classes;
thus the kernel class index values are compressed. The flask.h
definitions were regenerated by deleting the userspace classes from
refpolicy's definitions and then regenerating the headers. Going
forward, we can just maintain the flask.h, av_permissions.h, and
classmap.h definitions separately from policy as they are no longer
tied to the policy values. The next patch introduces a utility to
automate generation of flask.h and av_permissions.h from the
classmap.h definitions.
The older kernel class and permission string tables are removed and
replaced by a single security class mapping table that is walked at
policy load to generate the mapping. The old kernel class validation
logic is completely replaced by the mapping logic.
The handle unknown logic is reworked. reject_unknown=1 is handled
when the mappings are computed at policy load time, similar to the old
handling by the class validation logic. allow_unknown=1 is handled
when computing and mapping decisions - if the permission was not able
to be mapped (i.e. undefined, mapped to zero), then it is
automatically added to the allowed vector. If the class was not able
to be mapped (i.e. undefined, mapped to zero), then all permissions
are allowed for it if allow_unknown=1.
avc_audit leverages the new security class mapping table to lookup the
class and permission names from the kernel-private indices.
The mdp program is updated to use the new table when generating the
class definitions and allow rules for a minimal boot policy for the
kernel. It should be noted that this policy will not include any
userspace classes, nor will its policy index values for the kernel
classes correspond with the ones in refpolicy (they will instead match
the kernel-private indices).
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
This patch resets the security_ops to the secondary_ops before it flushes
the avc. It's still possible that a task on another processor could have
already passed the security_ops dereference and be executing an selinux hook
function which would add a new avc entry. That entry would still not be
freed. This should however help to reduce the number of needless avcs the
kernel has when selinux is disabled at run time. There is no wasted
memory if selinux is disabled on the command line or not compiled.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Ratan Nalumasu reported that in a process with many threads doing
unnecessary wakeups. Every waiting thread in the process wakes up to loop
through the children and see that the only ones it cares about are still
not ready.
Now that we have struct wait_opts we can change do_wait/__wake_up_parent
to use filtered wakeups.
We can make child_wait_callback() more clever later, right now it only
checks eligible_child().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ratan Nalumasu <rnalumasu@gmail.com>
Cc: Vitaly Mayatskikh <vmayatsk@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Tested-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Before SELinux is disabled at boot it can create AVC entries. This patch
will flush those entries before disabling SELinux.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Move the avc_cache flushing into it's own function so it can be reused when
disabling SELinux.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
__validate_process_creds should check if selinux is actually enabled before
running tests on the selinux portion of the credentials struct.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch adds a setxattr handler to the file, directory, and symlink
inode_operations structures for sysfs. The patch uses hooks introduced in the
previous patch to handle the getting and setting of security information for
the sysfs inodes. As was suggested by Eric Biederman the struct iattr in the
sysfs_dirent structure has been replaced by a structure which contains the
iattr, secdata and secdata length to allow the changes to persist in the event
that the inode representing the sysfs_dirent is evicted. Because sysfs only
stores this information when a change is made all the optional data is moved
into one dynamically allocated field.
This patch addresses an issue where SELinux was denying virtd access to the PCI
configuration entries in sysfs. The lack of setxattr handlers for sysfs
required that a single label be assigned to all entries in sysfs. Granting virtd
access to every entry in sysfs is not an acceptable solution so fine grained
labeling of sysfs is required such that individual entries can be labeled
appropriately.
[sds: Fixed compile-time warnings, coding style, and setting of inode security init flags.]
Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov>
Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
This patch introduces three new hooks. The inode_getsecctx hook is used to get
all relevant information from an LSM about an inode. The inode_setsecctx is
used to set both the in-core and on-disk state for the inode based on a context
derived from inode_getsecctx.The final hook inode_notifysecctx will notify the
LSM of a change for the in-core state of the inode in question. These hooks are
for use in the labeled NFS code and addresses concerns of how to set security
on an inode in a multi-xattr LSM. For historical reasons Stephen Smalley's
explanation of the reason for these hooks is pasted below.
Quote Stephen Smalley
inode_setsecctx: Change the security context of an inode. Updates the
in core security context managed by the security module and invokes the
fs code as needed (via __vfs_setxattr_noperm) to update any backing
xattrs that represent the context. Example usage: NFS server invokes
this hook to change the security context in its incore inode and on the
backing file system to a value provided by the client on a SETATTR
operation.
inode_notifysecctx: Notify the security module of what the security
context of an inode should be. Initializes the incore security context
managed by the security module for this inode. Example usage: NFS
client invokes this hook to initialize the security context in its
incore inode to the value provided by the server for the file when the
server returned the file's attributes to the client.
Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Add a keyctl to install a process's session keyring onto its parent. This
replaces the parent's session keyring. Because the COW credential code does
not permit one process to change another process's credentials directly, the
change is deferred until userspace next starts executing again. Normally this
will be after a wait*() syscall.
To support this, three new security hooks have been provided:
cred_alloc_blank() to allocate unset security creds, cred_transfer() to fill in
the blank security creds and key_session_to_parent() - which asks the LSM if
the process may replace its parent's session keyring.
The replacement may only happen if the process has the same ownership details
as its parent, and the process has LINK permission on the session keyring, and
the session keyring is owned by the process, and the LSM permits it.
Note that this requires alteration to each architecture's notify_resume path.
This has been done for all arches barring blackfin, m68k* and xtensa, all of
which need assembly alteration to support TIF_NOTIFY_RESUME. This allows the
replacement to be performed at the point the parent process resumes userspace
execution.
This allows the userspace AFS pioctl emulation to fully emulate newpag() and
the VIOCSETTOK and VIOCSETTOK2 pioctls, all of which require the ability to
alter the parent process's PAG membership. However, since kAFS doesn't use
PAGs per se, but rather dumps the keys into the session keyring, the session
keyring of the parent must be replaced if, for example, VIOCSETTOK is passed
the newpag flag.
This can be tested with the following program:
#include <stdio.h>
#include <stdlib.h>
#include <keyutils.h>
#define KEYCTL_SESSION_TO_PARENT 18
#define OSERROR(X, S) do { if ((long)(X) == -1) { perror(S); exit(1); } } while(0)
int main(int argc, char **argv)
{
key_serial_t keyring, key;
long ret;
keyring = keyctl_join_session_keyring(argv[1]);
OSERROR(keyring, "keyctl_join_session_keyring");
key = add_key("user", "a", "b", 1, keyring);
OSERROR(key, "add_key");
ret = keyctl(KEYCTL_SESSION_TO_PARENT);
OSERROR(ret, "KEYCTL_SESSION_TO_PARENT");
return 0;
}
Compiled and linked with -lkeyutils, you should see something like:
[dhowells@andromeda ~]$ keyctl show
Session Keyring
-3 --alswrv 4043 4043 keyring: _ses
355907932 --alswrv 4043 -1 \_ keyring: _uid.4043
[dhowells@andromeda ~]$ /tmp/newpag
[dhowells@andromeda ~]$ keyctl show
Session Keyring
-3 --alswrv 4043 4043 keyring: _ses
1055658746 --alswrv 4043 4043 \_ user: a
[dhowells@andromeda ~]$ /tmp/newpag hello
[dhowells@andromeda ~]$ keyctl show
Session Keyring
-3 --alswrv 4043 4043 keyring: hello
340417692 --alswrv 4043 4043 \_ user: a
Where the test program creates a new session keyring, sticks a user key named
'a' into it and then installs it on its parent.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Add a config option (CONFIG_DEBUG_CREDENTIALS) to turn on some debug checking
for credential management. The additional code keeps track of the number of
pointers from task_structs to any given cred struct, and checks to see that
this number never exceeds the usage count of the cred struct (which includes
all references, not just those from task_structs).
Furthermore, if SELinux is enabled, the code also checks that the security
pointer in the cred struct is never seen to be invalid.
This attempts to catch the bug whereby inode_has_perm() faults in an nfsd
kernel thread on seeing cred->security be a NULL pointer (it appears that the
credential struct has been previously released):
http://www.kerneloops.org/oops.php?number=252883
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Add support for the new TUN LSM hooks: security_tun_dev_create(),
security_tun_dev_post_create() and security_tun_dev_attach(). This includes
the addition of a new object class, tun_socket, which represents the socks
associated with TUN devices. The _tun_dev_create() and _tun_dev_post_create()
hooks are fairly similar to the standard socket functions but _tun_dev_attach()
is a bit special. The _tun_dev_attach() is unique because it involves a
domain attaching to an existing TUN device and its associated tun_socket
object, an operation which does not exist with standard sockets and most
closely resembles a relabel operation.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: Eric Paris <eparis@parisplace.org>
Signed-off-by: James Morris <jmorris@namei.org>
As suggested by OGAWA Hirofumi in thread:
http://lkml.org/lkml/2009/8/7/132, we should let selinux_inode_setattr()
to match our ATTR_* rules. ATTR_FORCE should not force things like
ATTR_SIZE.
[hirofumi@mail.parknet.co.jp: tweaks]
Signed-off-by: WANG Cong <amwang@redhat.com>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Eric Paris <eparis@redhat.com>
Cc: Eugene Teo <eteo@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Morris <jmorris@namei.org>
Currently SELinux enforcement of controls on the ability to map low memory
is determined by the mmap_min_addr tunable. This patch causes SELinux to
ignore the tunable and instead use a seperate Kconfig option specific to how
much space the LSM should protect.
The tunable will now only control the need for CAP_SYS_RAWIO and SELinux
permissions will always protect the amount of low memory designated by
CONFIG_LSM_MMAP_MIN_ADDR.
This allows users who need to disable the mmap_min_addr controls (usual reason
being they run WINE as a non-root user) to do so and still have SELinux
controls preventing confined domains (like a web server) from being able to
map some area of low memory.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Currently SELinux does not check CAP_SYS_RAWIO in the file_mmap hook. This
means there is no DAC check on the ability to mmap low addresses in the
memory space. This function adds the DAC check for CAP_SYS_RAWIO while
maintaining the selinux check on mmap_zero. This means that processes
which need to mmap low memory will need CAP_SYS_RAWIO and mmap_zero but will
NOT need the SELinux sys_rawio capability.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Convert avc_audit in security/selinux/avc.c to use lsm_audit.h,
for better maintainability.
- changed selinux to use common_audit_data instead of
avc_audit_data
- eliminated code in avc.c and used code from lsm_audit.h instead.
Had to add a LSM_AUDIT_NO_AUDIT to lsm_audit.h so that avc_audit
can call common_lsm_audit and do the pre and post callbacks without
doing the actual dump. This makes it so that the patched version
behaves the same way as the unpatched version.
Also added a denied field to the selinux_audit_data private space,
once again to make it so that the patched version behaves like the
unpatched.
I've tested and confirmed that AVCs look the same before and after
this patch.
Signed-off-by: Thomas Liu <tliu@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
This patch adds a new selinux hook so SELinux can arbitrate if a given
process should be allowed to trigger a request for the kernel to try to
load a module. This is a different operation than a process trying to load
a module itself, which is already protected by CAP_SYS_MODULE.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Fix memory leakage in /security/selinux/hooks.c
The buffer always needs to be freed here; we either error
out or allocate more memory.
Reported-by: iceberg <strakh@ispras.ru>
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Currently SELinux enforcement of controls on the ability to map low memory
is determined by the mmap_min_addr tunable. This patch causes SELinux to
ignore the tunable and instead use a seperate Kconfig option specific to how
much space the LSM should protect.
The tunable will now only control the need for CAP_SYS_RAWIO and SELinux
permissions will always protect the amount of low memory designated by
CONFIG_LSM_MMAP_MIN_ADDR.
This allows users who need to disable the mmap_min_addr controls (usual reason
being they run WINE as a non-root user) to do so and still have SELinux
controls preventing confined domains (like a web server) from being able to
map some area of low memory.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Currently SELinux does not check CAP_SYS_RAWIO in the file_mmap hook. This
means there is no DAC check on the ability to mmap low addresses in the
memory space. This function adds the DAC check for CAP_SYS_RAWIO while
maintaining the selinux check on mmap_zero. This means that processes
which need to mmap low memory will need CAP_SYS_RAWIO and mmap_zero but will
NOT need the SELinux sys_rawio capability.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
- is_single_threaded(task) is not safe unless task == current,
we can't use task->signal or task->mm.
- it doesn't make sense unless task == current, the task can
fork right after the check.
Rename it to current_is_single_threaded() and kill the argument.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Convert avc_audit in security/selinux/avc.c to use lsm_audit.h,
for better maintainability and for less code duplication.
- changed selinux to use common_audit_data instead of
avc_audit_data
- eliminated code in avc.c and used code from lsm_audit.h instead.
I have tested to make sure that the avcs look the same before and
after this patch.
Signed-off-by: Thomas Liu <tliu@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Added a call to free the avc_node_cache when inside selinux_disable because
it should not waste resources allocated during avc_init if SELinux is disabled
and the cache will never be used.
Signed-off-by: Thomas Liu <tliu@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
The ->ptrace_may_access() methods are named confusingly - the real
ptrace_may_access() returns a bool, while these security checks have
a retval convention.
Rename it to ptrace_access_check, to reduce the confusion factor.
[ Impact: cleanup, no code changed ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: James Morris <jmorris@namei.org>
Restore the optimization to skip revalidation in selinux_file_permission
if nothing has changed since the dentry_open checks, accidentally removed by
389fb800. Also remove redundant test from selinux_revalidate_file_permission.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
The attached patch adds support to generate audit messages on two cases.
The first one is a case when a multi-thread process tries to switch its
performing security context using setcon(3), but new security context is
not bounded by the old one.
type=SELINUX_ERR msg=audit(1245311998.599:17): \
op=security_bounded_transition result=denied \
oldcontext=system_u:system_r:httpd_t:s0 \
newcontext=system_u:system_r:guest_webapp_t:s0
The other one is a case when security_compute_av() masked any permissions
due to the type boundary violation.
type=SELINUX_ERR msg=audit(1245312836.035:32): \
op=security_compute_av reason=bounds \
scontext=system_u:object_r:user_webapp_t:s0 \
tcontext=system_u:object_r:shadow_t:s0:c0 \
tclass=file perms=getattr,open
Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
It is a cleanup patch to cut down a line within 80 columns.
Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
--
security/selinux/ss/services.c | 6 +++---
1 files changed, 3 insertions(+), 3 deletions(-)
Signed-off-by: James Morris <jmorris@namei.org>
Define three accessors to get/set dst attached to a skb
struct dst_entry *skb_dst(const struct sk_buff *skb)
void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst)
void skb_dst_drop(struct sk_buff *skb)
This one should replace occurrences of :
dst_release(skb->dst)
skb->dst = NULL;
Delete skb->dst field
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Audit trees defined 2 new netlink messages but the netlink mapping tables for
selinux permissions were not set up. This patch maps these 2 new operations
to AUDIT_WRITE.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
On Tue, 2009-05-19 at 00:05 -0400, Eamon Walsh wrote:
> Recent versions of coreutils have bumped the read buffer size from 4K to
> 32K in several of the utilities.
>
> This means that "cat /selinux/booleans/xserver_object_manager" no longer
> works, it returns "Invalid argument" on F11. getsebool works fine.
>
> sel_read_bool has a check for "count > PAGE_SIZE" that doesn't seem to
> be present in the other read functions. Maybe it could be removed?
Yes, that check is obsoleted by the conversion of those functions to
using simple_read_from_buffer(), which will reduce count if necessary to
what is available in the buffer.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
The selinuxfs superblock magic is used inside the IMA code, but is being
defined in two places and could someday get out of sync. This patch moves the
declaration into magic.h so it is only done once.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
The CRED patch incorrectly converted the SELinux send_sigiotask hook to
use the current task SID rather than the target task SID in its
permission check, yielding the wrong permission check. This fixes the
hook function. Detected by the ltp selinux testsuite and confirmed to
correct the test failure.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
We shouldn't worry about the tracer if current is ptraced, exec() must not
succeed if the tracer has no rights to trace this task after cred changing.
But we should notify ->real_parent which is, well, real parent.
Also, we don't need _irq to take tasklist, and we don't need parent's
->siglock to wake_up_interruptible(real_parent->signal->wait_chldexit).
Since we hold tasklist, real_parent->signal must be stable. Otherwise
spin_lock(siglock) is not safe too and can't help anyway.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Don't flush inherited SIGKILL during execve() in SELinux's post cred commit
hook. This isn't really a security problem: if the SIGKILL came before the
credentials were changed, then we were right to receive it at the time, and
should honour it; if it came after the creds were changed, then we definitely
should honour it; and in any case, all that will happen is that the process
will be scrapped before it ever returns to userspace.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
We are still calling secondary_ops->sysctl even though the capabilities
module does not define a sysctl operation.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
This patch enables applications to handle permissive domain correctly.
Since the v2.6.26 kernel, SELinux has supported an idea of permissive
domain which allows certain processes to work as if permissive mode,
even if the global setting is enforcing mode.
However, we don't have an application program interface to inform
what domains are permissive one, and what domains are not.
It means applications focuses on SELinux (XACE/SELinux, SE-PostgreSQL
and so on) cannot handle permissive domain correctly.
This patch add the sixth field (flags) on the reply of the /selinux/access
interface which is used to make an access control decision from userspace.
If the first bit of the flags field is positive, it means the required
access control decision is on permissive domain, so application should
allow any required actions, as the kernel doing.
This patch also has a side benefit. The av_decision.flags is set at
context_struct_compute_av(). It enables to check required permissions
without read_lock(&policy_rwlock).
Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Eric Paris <eparis@redhat.com>
--
security/selinux/avc.c | 2 +-
security/selinux/include/security.h | 4 +++-
security/selinux/selinuxfs.c | 4 ++--
security/selinux/ss/services.c | 30 +++++-------------------------
4 files changed, 11 insertions(+), 29 deletions(-)
Signed-off-by: James Morris <jmorris@namei.org>
The SELinux "compat_net" is marked as deprecated, the time has come to
finally remove it from the kernel. Further code simplifications are
likely in the future, but this patch was intended to be a simple,
straight-up removal of the compat_net code.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
The current NetLabel/SELinux behavior for incoming TCP connections works but
only through a series of happy coincidences that rely on the limited nature of
standard CIPSO (only able to convey MLS attributes) and the write equality
imposed by the SELinux MLS constraints. The problem is that network sockets
created as the result of an incoming TCP connection were not on-the-wire
labeled based on the security attributes of the parent socket but rather based
on the wire label of the remote peer. The issue had to do with how IP options
were managed as part of the network stack and where the LSM hooks were in
relation to the code which set the IP options on these newly created child
sockets. While NetLabel/SELinux did correctly set the socket's on-the-wire
label it was promptly cleared by the network stack and reset based on the IP
options of the remote peer.
This patch, in conjunction with a prior patch that adjusted the LSM hook
locations, works to set the correct on-the-wire label format for new incoming
connections through the security_inet_conn_request() hook. Besides the
correct behavior there are many advantages to this change, the most significant
is that all of the NetLabel socket labeling code in SELinux now lives in hooks
which can return error codes to the core stack which allows us to finally get
ride of the selinux_netlbl_inode_permission() logic which greatly simplfies
the NetLabel/SELinux glue code. In the process of developing this patch I
also ran into a small handful of AF_INET6 cleanliness issues that have been
fixed which should make the code safer and easier to extend in the future.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: James Morris <jmorris@namei.org>
Drop the printk message when an inode is found without an associated
dentry. This should only happen when userspace can't be accessing those
inodes and those labels will get set correctly on the next d_instantiate.
Thus there is no reason to send this message.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
New selinux permission to separate the ability to turn on tty auditing from
the ability to set audit rules.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
When I did open permissions I didn't think any sockets would have an open.
Turns out AF_UNIX sockets can have an open when they are bound to the
filesystem namespace. This patch adds a new SOCK_FILE__OPEN permission.
It's safe to add this as the open perms are already predicated on
capabilities and capabilities means we have unknown perm handling so
systems should be as backwards compatible as the policy wants them to
be.
https://bugzilla.redhat.com/show_bug.cgi?id=475224
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Rick McNeal from LSI identified a panic in selinux_netlbl_inode_permission()
caused by a certain sequence of SUNRPC operations. The problem appears to be
due to the lack of NULL pointer checking in the function; this patch adds the
pointer checks so the function will exit safely in the cases where the socket
is not completely initialized.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
At some point we (okay, I) managed to break the ability for users to use the
setsockopt() syscall to set IPv4 options when NetLabel was not active on the
socket in question. The problem was noticed by someone trying to use the
"-R" (record route) option of ping:
# ping -R 10.0.0.1
ping: record route: No message of desired type
The solution is relatively simple, we catch the unlabeled socket case and
clear the error code, allowing the operation to succeed. Please note that we
still deny users the ability to override IPv4 options on socket's which have
NetLabel labeling active; this is done to ensure the labeling remains intact.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
We do not need O(1) access to the tail of the avc cache lists and so we are
wasting lots of space using struct list_head instead of struct hlist_head.
This patch converts the avc cache to use hlists in which there is a single
pointer from the head which saves us about 4k of global memory.
Resulted in about a 1.5% decrease in time spent in avc_has_perm_noaudit based
on oprofile sampling of tbench. Although likely within the noise....
Signed-off-by: Eric Paris <eparis@redhat.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
The code making use of struct avc_cache was not easy to read thanks to liberal
use of &avc_cache.{slots_lock,slots}[hvalue] throughout. This patch simply
creates local pointers and uses those instead of the long global names.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
It appears there was an intention to have the security server only decide
certain permissions and leave other for later as some sort of a portential
performance win. We are currently always deciding all 32 bits of
permissions and this is a useless couple of branches and wasted space.
This patch completely drops the av.decided concept.
This in a 17% reduction in the time spent in avc_has_perm_noaudit
based on oprofile sampling of a tbench benchmark.
Signed-off-by: Eric Paris <eparis@redhat.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
we are often needlessly jumping through hoops when it comes to avd
entries in avc_has_perm_noaudit and we have extra initialization and memcpy
which are just wasting performance. Try to clean the function up a bit.
This patch resulted in a 13% drop in time spent in avc_has_perm_noaudit in my
oprofile sampling of a tbench benchmark.
Signed-off-by: Eric Paris <eparis@redhat.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Currently SELinux code has an atomic which was intended to track how many
times an avc entry was used and to evict entries when they haven't been
used recently. Instead we never let this atomic get above 1 and evict when
it is first checked for eviction since it hits zero. This is a total waste
of time so I'm completely dropping ae.used.
This change resulted in about a 3% faster avc_has_perm_noaudit when running
oprofile against a tbench benchmark.
Signed-off-by: Eric Paris <eparis@redhat.com>
Reviewed by: Paul Moore <paul.moore@hp.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
The avc update node callbacks do not check the seqno of the caller with the
seqno of the node found. It is possible that a policy change could happen
(although almost impossibly unlikely) in which a permissive or
permissive_domain decision is not valid for the entry found. Simply pass
and check that the seqno of the caller and the seqno of the node found
match.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
When a context is pulled in from disk we don't know that it is null
terminated. This patch forecebly null terminates contexts when we pull
them from disk.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Currently when an inode is read into the kernel with an invalid label
string (can often happen with removable media) we output a string like:
SELinux: inode_doinit_with_dentry: context_to_sid([SOME INVALID LABEL])
returned -22 dor dev=[blah] ino=[blah]
Which is all but incomprehensible to all but a couple of us. Instead, on
EINVAL only, I plan to output a much more user friendly string and I plan to
ratelimit the printk since many of these could be generated very rapidly.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
For cleanliness and efficiency remove all calls to secondary-> and instead
call capabilities code directly. capabilities are the only module that
selinux stacks with and so the code should not indicate that other stacking
might be possible.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Remove SELinux hooks which do nothing except defer to the capabilites
hooks (or in one case, replicates the function).
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Remove secondary ops call to shm_shmat, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove secondary ops call to unix_stream_connect, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove secondary ops call to task_kill, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove secondary ops call to task_setrlimit, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove unused cred_commit hook from SELinux. This
currently calls into the capabilities hook, which is a noop.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove secondary ops call to task_create, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove secondary ops call to file_mprotect, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove secondary ops call to inode_setattr, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove secondary ops call to inode_permission, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove secondary ops call to inode_follow_link, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove secondary ops call to inode_mknod, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove secondary ops call to inode_unlink, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove secondary ops call to inode_link, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove secondary ops call to sb_umount, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove secondary ops call to sb_mount, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove secondary ops call to bprm_committed_creds, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove secondary ops call to bprm_committing_creds, which is
a noop in capabilities.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Remove unused bprm_check_security hook from SELinux. This
currently calls into the capabilities hook, which is a noop.
Acked-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Context mounts and genfs labeled file systems behave differently with respect to
setting file system labels. This patch brings genfs labeled file systems in line
with context mounts in that setxattr calls to them should return EOPNOTSUPP and
fscreate calls will be ignored.
Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@macbook.localdomain>
There is no easy way to tell if a file system supports SELinux security labeling.
Because of this a new flag is being added to the super block security structure
to indicate that the particular super block supports labeling. This flag is set
for file systems using the xattr, task, and transition labeling methods unless
that behavior is overridden by context mounts.
Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@macbook.localdomain>
The super block security structure currently has three fields for what are
essentially flags. The flags field is used for mount options while two other
char fields are used for initialization and proc flags. These latter two fields are
essentially bit fields since the only used values are 0 and 1. These fields
have been collapsed into the flags field and new bit masks have been added for
them. The code is also fixed to work with these new flags.
Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@macbook.localdomain>
Fix a regression in cap_capable() due to:
commit 3b11a1dece
Author: David Howells <dhowells@redhat.com>
Date: Fri Nov 14 10:39:26 2008 +1100
CRED: Differentiate objective and effective subjective credentials on a task
The problem is that the above patch allows a process to have two sets of
credentials, and for the most part uses the subjective credentials when
accessing current's creds.
There is, however, one exception: cap_capable(), and thus capable(), uses the
real/objective credentials of the target task, whether or not it is the current
task.
Ordinarily this doesn't matter, since usually the two cred pointers in current
point to the same set of creds. However, sys_faccessat() makes use of this
facility to override the credentials of the calling process to make its test,
without affecting the creds as seen from other processes.
One of the things sys_faccessat() does is to make an adjustment to the
effective capabilities mask, which cap_capable(), as it stands, then ignores.
The affected capability check is in generic_permission():
if (!(mask & MAY_EXEC) || execute_ok(inode))
if (capable(CAP_DAC_OVERRIDE))
return 0;
This change passes the set of credentials to be tested down into the commoncap
and SELinux code. The security functions called by capable() and
has_capability() select the appropriate set of credentials from the process
being checked.
This can be tested by compiling the following program from the XFS testsuite:
/*
* t_access_root.c - trivial test program to show permission bug.
*
* Written by Michael Kerrisk - copyright ownership not pursued.
* Sourced from: http://linux.derkeiler.com/Mailing-Lists/Kernel/2003-10/6030.html
*/
#include <limits.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sys/stat.h>
#define UID 500
#define GID 100
#define PERM 0
#define TESTPATH "/tmp/t_access"
static void
errExit(char *msg)
{
perror(msg);
exit(EXIT_FAILURE);
} /* errExit */
static void
accessTest(char *file, int mask, char *mstr)
{
printf("access(%s, %s) returns %d\n", file, mstr, access(file, mask));
} /* accessTest */
int
main(int argc, char *argv[])
{
int fd, perm, uid, gid;
char *testpath;
char cmd[PATH_MAX + 20];
testpath = (argc > 1) ? argv[1] : TESTPATH;
perm = (argc > 2) ? strtoul(argv[2], NULL, 8) : PERM;
uid = (argc > 3) ? atoi(argv[3]) : UID;
gid = (argc > 4) ? atoi(argv[4]) : GID;
unlink(testpath);
fd = open(testpath, O_RDWR | O_CREAT, 0);
if (fd == -1) errExit("open");
if (fchown(fd, uid, gid) == -1) errExit("fchown");
if (fchmod(fd, perm) == -1) errExit("fchmod");
close(fd);
snprintf(cmd, sizeof(cmd), "ls -l %s", testpath);
system(cmd);
if (seteuid(uid) == -1) errExit("seteuid");
accessTest(testpath, 0, "0");
accessTest(testpath, R_OK, "R_OK");
accessTest(testpath, W_OK, "W_OK");
accessTest(testpath, X_OK, "X_OK");
accessTest(testpath, R_OK | W_OK, "R_OK | W_OK");
accessTest(testpath, R_OK | X_OK, "R_OK | X_OK");
accessTest(testpath, W_OK | X_OK, "W_OK | X_OK");
accessTest(testpath, R_OK | W_OK | X_OK, "R_OK | W_OK | X_OK");
exit(EXIT_SUCCESS);
} /* main */
This can be run against an Ext3 filesystem as well as against an XFS
filesystem. If successful, it will show:
[root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043
---------- 1 dhowells dhowells 0 2008-12-31 03:00 /tmp/xxx
access(/tmp/xxx, 0) returns 0
access(/tmp/xxx, R_OK) returns 0
access(/tmp/xxx, W_OK) returns 0
access(/tmp/xxx, X_OK) returns -1
access(/tmp/xxx, R_OK | W_OK) returns 0
access(/tmp/xxx, R_OK | X_OK) returns -1
access(/tmp/xxx, W_OK | X_OK) returns -1
access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1
If unsuccessful, it will show:
[root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043
---------- 1 dhowells dhowells 0 2008-12-31 02:56 /tmp/xxx
access(/tmp/xxx, 0) returns 0
access(/tmp/xxx, R_OK) returns -1
access(/tmp/xxx, W_OK) returns -1
access(/tmp/xxx, X_OK) returns -1
access(/tmp/xxx, R_OK | W_OK) returns -1
access(/tmp/xxx, R_OK | X_OK) returns -1
access(/tmp/xxx, W_OK | X_OK) returns -1
access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1
I've also tested the fix with the SELinux and syscalls LTP testsuites.
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: J. Bruce Fields <bfields@citi.umich.edu>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
inotify: fix type errors in interfaces
fix breakage in reiserfs_new_inode()
fix the treatment of jfs special inodes
vfs: remove duplicate code in get_fs_type()
add a vfs_fsync helper
sys_execve and sys_uselib do not call into fsnotify
zero i_uid/i_gid on inode allocation
inode->i_op is never NULL
ntfs: don't NULL i_op
isofs check for NULL ->i_op in root directory is dead code
affs: do not zero ->i_op
kill suid bit only for regular files
vfs: lseek(fd, 0, SEEK_CUR) race condition
... and don't bother in callers. Don't bother with zeroing i_blocks,
while we are at it - it's already been zeroed.
i_mode is not worth the effort; it has no common default value.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
I started playing with pahole today and decided to put it against the
selinux structures. Found we could save a little bit of space on x86_64
(and no harm on i686) just reorganizing some structs.
Object size changes:
av_inherit: 24 -> 16
selinux_class_perm: 48 -> 40
context: 80 -> 72
Admittedly there aren't many of av_inherit or selinux_class_perm's in
the kernel (33 and 1 respectively) But the change to the size of struct
context reverberate out a bit. I can get some hard number if they are
needed, but I don't see why they would be. We do change which cacheline
context->len and context->str would be on, but I don't see that as a
problem since we are clearly going to have to load both if the context
is to be of any value. I've run with the patch and don't seem to be
having any problems.
An example of what's going on using struct av_inherit would be:
form: to:
struct av_inherit { struct av_inherit {
u16 tclass; const char **common_pts;
const char **common_pts; u32 common_base;
u32 common_base; u16 tclass;
};
(notice all I did was move u16 tclass to the end of the struct instead
of the beginning)
Memory layout before the change:
struct av_inherit {
u16 tclass; /* 2 */
/* 6 bytes hole */
const char** common_pts; /* 8 */
u32 common_base; /* 4 */
/* 4 byes padding */
/* size: 24, cachelines: 1 */
/* sum members: 14, holes: 1, sum holes: 6 */
/* padding: 4 */
};
Memory layout after the change:
struct av_inherit {
const char ** common_pts; /* 8 */
u32 common_base; /* 4 */
u16 tclass; /* 2 */
/* 2 bytes padding */
/* size: 16, cachelines: 1 */
/* sum members: 14, holes: 0, sum holes: 0 */
/* padding: 2 */
};
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Fix a regression in cap_capable() due to:
commit 5ff7711e635b32f0a1e558227d030c7e45b4a465
Author: David Howells <dhowells@redhat.com>
Date: Wed Dec 31 02:52:28 2008 +0000
CRED: Differentiate objective and effective subjective credentials on a task
The problem is that the above patch allows a process to have two sets of
credentials, and for the most part uses the subjective credentials when
accessing current's creds.
There is, however, one exception: cap_capable(), and thus capable(), uses the
real/objective credentials of the target task, whether or not it is the current
task.
Ordinarily this doesn't matter, since usually the two cred pointers in current
point to the same set of creds. However, sys_faccessat() makes use of this
facility to override the credentials of the calling process to make its test,
without affecting the creds as seen from other processes.
One of the things sys_faccessat() does is to make an adjustment to the
effective capabilities mask, which cap_capable(), as it stands, then ignores.
The affected capability check is in generic_permission():
if (!(mask & MAY_EXEC) || execute_ok(inode))
if (capable(CAP_DAC_OVERRIDE))
return 0;
This change splits capable() from has_capability() down into the commoncap and
SELinux code. The capable() security op now only deals with the current
process, and uses the current process's subjective creds. A new security op -
task_capable() - is introduced that can check any task's objective creds.
strictly the capable() security op is superfluous with the presence of the
task_capable() op, however it should be faster to call the capable() op since
two fewer arguments need be passed down through the various layers.
This can be tested by compiling the following program from the XFS testsuite:
/*
* t_access_root.c - trivial test program to show permission bug.
*
* Written by Michael Kerrisk - copyright ownership not pursued.
* Sourced from: http://linux.derkeiler.com/Mailing-Lists/Kernel/2003-10/6030.html
*/
#include <limits.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sys/stat.h>
#define UID 500
#define GID 100
#define PERM 0
#define TESTPATH "/tmp/t_access"
static void
errExit(char *msg)
{
perror(msg);
exit(EXIT_FAILURE);
} /* errExit */
static void
accessTest(char *file, int mask, char *mstr)
{
printf("access(%s, %s) returns %d\n", file, mstr, access(file, mask));
} /* accessTest */
int
main(int argc, char *argv[])
{
int fd, perm, uid, gid;
char *testpath;
char cmd[PATH_MAX + 20];
testpath = (argc > 1) ? argv[1] : TESTPATH;
perm = (argc > 2) ? strtoul(argv[2], NULL, 8) : PERM;
uid = (argc > 3) ? atoi(argv[3]) : UID;
gid = (argc > 4) ? atoi(argv[4]) : GID;
unlink(testpath);
fd = open(testpath, O_RDWR | O_CREAT, 0);
if (fd == -1) errExit("open");
if (fchown(fd, uid, gid) == -1) errExit("fchown");
if (fchmod(fd, perm) == -1) errExit("fchmod");
close(fd);
snprintf(cmd, sizeof(cmd), "ls -l %s", testpath);
system(cmd);
if (seteuid(uid) == -1) errExit("seteuid");
accessTest(testpath, 0, "0");
accessTest(testpath, R_OK, "R_OK");
accessTest(testpath, W_OK, "W_OK");
accessTest(testpath, X_OK, "X_OK");
accessTest(testpath, R_OK | W_OK, "R_OK | W_OK");
accessTest(testpath, R_OK | X_OK, "R_OK | X_OK");
accessTest(testpath, W_OK | X_OK, "W_OK | X_OK");
accessTest(testpath, R_OK | W_OK | X_OK, "R_OK | W_OK | X_OK");
exit(EXIT_SUCCESS);
} /* main */
This can be run against an Ext3 filesystem as well as against an XFS
filesystem. If successful, it will show:
[root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043
---------- 1 dhowells dhowells 0 2008-12-31 03:00 /tmp/xxx
access(/tmp/xxx, 0) returns 0
access(/tmp/xxx, R_OK) returns 0
access(/tmp/xxx, W_OK) returns 0
access(/tmp/xxx, X_OK) returns -1
access(/tmp/xxx, R_OK | W_OK) returns 0
access(/tmp/xxx, R_OK | X_OK) returns -1
access(/tmp/xxx, W_OK | X_OK) returns -1
access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1
If unsuccessful, it will show:
[root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043
---------- 1 dhowells dhowells 0 2008-12-31 02:56 /tmp/xxx
access(/tmp/xxx, 0) returns 0
access(/tmp/xxx, R_OK) returns -1
access(/tmp/xxx, W_OK) returns -1
access(/tmp/xxx, X_OK) returns -1
access(/tmp/xxx, R_OK | W_OK) returns -1
access(/tmp/xxx, R_OK | X_OK) returns -1
access(/tmp/xxx, W_OK | X_OK) returns -1
access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1
I've also tested the fix with the SELinux and syscalls LTP testsuites.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Don't store the field->op in the messy (and very inconvenient for e.g.
audit_comparator()) form; translate to dense set of values and do full
validation of userland-submitted value while we are at it.
->audit_init_rule() and ->audit_match_rule() get new values now; in-tree
instances updated.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Impact: cleanup
In future, all cpumask ops will only be valid (in general) for bit
numbers < nr_cpu_ids. So use that instead of NR_CPUS in iterators
and other comparisons.
This is always safe: no cpu number can be >= nr_cpu_ids, and
nr_cpu_ids is initialized to NR_CPUS at boot.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: James Morris <jmorris@namei.org>
Cc: Eric Biederman <ebiederm@xmission.com>
This patch is the first step towards removing the old "compat_net" code from
the kernel. Secmark, the "compat_net" replacement was first introduced in
2.6.18 (September 2006) and the major Linux distributions with SELinux support
have transitioned to Secmark so it is time to start deprecating the "compat_net"
mechanism. Testing a patched version of 2.6.28-rc6 with the initial release of
Fedora Core 5 did not show any problems when running in enforcing mode.
This patch adds an entry to the feature-removal-schedule.txt file and removes
the SECURITY_SELINUX_ENABLE_SECMARK_DEFAULT configuration option, forcing
Secmark on by default although it can still be disabled at runtime. The patch
also makes the Secmark permission checks "dynamic" in the sense that they are
only executed when Secmark is configured; this should help prevent problems
with older distributions that have not yet migrated to Secmark.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1429 commits)
net: Allow dependancies of FDDI & Tokenring to be modular.
igb: Fix build warning when DCA is disabled.
net: Fix warning fallout from recent NAPI interface changes.
gro: Fix potential use after free
sfc: If AN is enabled, always read speed/duplex from the AN advertising bits
sfc: When disabling the NIC, close the device rather than unregistering it
sfc: SFT9001: Add cable diagnostics
sfc: Add support for multiple PHY self-tests
sfc: Merge top-level functions for self-tests
sfc: Clean up PHY mode management in loopback self-test
sfc: Fix unreliable link detection in some loopback modes
sfc: Generate unique names for per-NIC workqueues
802.3ad: use standard ethhdr instead of ad_header
802.3ad: generalize out mac address initializer
802.3ad: initialize ports LACPDU from const initializer
802.3ad: remove typedef around ad_system
802.3ad: turn ports is_individual into a bool
802.3ad: turn ports is_enabled into a bool
802.3ad: make ntt bool
ixgbe: Fix set_ringparam in ixgbe to use the same memory pools.
...
Fixed trivial IPv4/6 address printing conflicts in fs/cifs/connect.c due
to the conversion to %pI (in this networking merge) and the addition of
doing IPv6 addresses (from the earlier merge of CIFS).
Don't bother checking permissions when the kernel performs an
internal mount, as this should always be allowed.
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Pass mount flags to security_sb_kern_mount(), so security modules
can determine if a mount operation is being performed by the kernel.
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Allow kernel services to override LSM settings appropriate to the actions
performed by a task by duplicating a set of credentials, modifying it and then
using task_struct::cred to point to it when performing operations on behalf of
a task.
This is used, for example, by CacheFiles which has to transparently access the
cache on behalf of a process that thinks it is doing, say, NFS accesses with a
potentially inappropriate (with respect to accessing the cache) set of
credentials.
This patch provides two LSM hooks for modifying a task security record:
(*) security_kernel_act_as() which allows modification of the security datum
with which a task acts on other objects (most notably files).
(*) security_kernel_create_files_as() which allows modification of the
security datum that is used to initialise the security data on a file that
a task creates.
The patch also provides four new credentials handling functions, which wrap the
LSM functions:
(1) prepare_kernel_cred()
Prepare a set of credentials for a kernel service to use, based either on
a daemon's credentials or on init_cred. All the keyrings are cleared.
(2) set_security_override()
Set the LSM security ID in a set of credentials to a specific security
context, assuming permission from the LSM policy.
(3) set_security_override_from_ctx()
As (2), but takes the security context as a string.
(4) set_create_files_as()
Set the file creation LSM security ID in a set of credentials to be the
same as that on a particular inode.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> [Smack changes]
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Add a 'kernel_service' object class to SELinux and give this object class two
access vectors: 'use_as_override' and 'create_files_as'.
The first vector is used to grant a process the right to nominate an alternate
process security ID for the kernel to use as an override for the SELinux
subjective security when accessing stuff on behalf of another process.
For example, CacheFiles when accessing the cache on behalf on a process
accessing an NFS file needs to use a subjective security ID appropriate to the
cache rather then the one the calling process is using. The cachefilesd
daemon will nominate the security ID to be used.
The second vector is used to grant a process the right to nominate a file
creation label for a kernel service to use.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Differentiate the objective and real subjective credentials from the effective
subjective credentials on a task by introducing a second credentials pointer
into the task_struct.
task_struct::real_cred then refers to the objective and apparent real
subjective credentials of a task, as perceived by the other tasks in the
system.
task_struct::cred then refers to the effective subjective credentials of a
task, as used by that task when it's actually running. These are not visible
to the other tasks in the system.
__task_cred(task) then refers to the objective/real credentials of the task in
question.
current_cred() refers to the effective subjective credentials of the current
task.
prepare_creds() uses the objective creds as a base and commit_creds() changes
both pointers in the task_struct (indeed commit_creds() requires them to be the
same).
override_creds() and revert_creds() change the subjective creds pointer only,
and the former returns the old subjective creds. These are used by NFSD,
faccessat() and do_coredump(), and will by used by CacheFiles.
In SELinux, current_has_perm() is provided as an alternative to
task_has_perm(). This uses the effective subjective context of current,
whereas task_has_perm() uses the objective/real context of the subject.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Make execve() take advantage of copy-on-write credentials, allowing it to set
up the credentials in advance, and then commit the whole lot after the point
of no return.
This patch and the preceding patches have been tested with the LTP SELinux
testsuite.
This patch makes several logical sets of alteration:
(1) execve().
The credential bits from struct linux_binprm are, for the most part,
replaced with a single credentials pointer (bprm->cred). This means that
all the creds can be calculated in advance and then applied at the point
of no return with no possibility of failure.
I would like to replace bprm->cap_effective with:
cap_isclear(bprm->cap_effective)
but this seems impossible due to special behaviour for processes of pid 1
(they always retain their parent's capability masks where normally they'd
be changed - see cap_bprm_set_creds()).
The following sequence of events now happens:
(a) At the start of do_execve, the current task's cred_exec_mutex is
locked to prevent PTRACE_ATTACH from obsoleting the calculation of
creds that we make.
(a) prepare_exec_creds() is then called to make a copy of the current
task's credentials and prepare it. This copy is then assigned to
bprm->cred.
This renders security_bprm_alloc() and security_bprm_free()
unnecessary, and so they've been removed.
(b) The determination of unsafe execution is now performed immediately
after (a) rather than later on in the code. The result is stored in
bprm->unsafe for future reference.
(c) prepare_binprm() is called, possibly multiple times.
(i) This applies the result of set[ug]id binaries to the new creds
attached to bprm->cred. Personality bit clearance is recorded,
but now deferred on the basis that the exec procedure may yet
fail.
(ii) This then calls the new security_bprm_set_creds(). This should
calculate the new LSM and capability credentials into *bprm->cred.
This folds together security_bprm_set() and parts of
security_bprm_apply_creds() (these two have been removed).
Anything that might fail must be done at this point.
(iii) bprm->cred_prepared is set to 1.
bprm->cred_prepared is 0 on the first pass of the security
calculations, and 1 on all subsequent passes. This allows SELinux
in (ii) to base its calculations only on the initial script and
not on the interpreter.
(d) flush_old_exec() is called to commit the task to execution. This
performs the following steps with regard to credentials:
(i) Clear pdeath_signal and set dumpable on certain circumstances that
may not be covered by commit_creds().
(ii) Clear any bits in current->personality that were deferred from
(c.i).
(e) install_exec_creds() [compute_creds() as was] is called to install the
new credentials. This performs the following steps with regard to
credentials:
(i) Calls security_bprm_committing_creds() to apply any security
requirements, such as flushing unauthorised files in SELinux, that
must be done before the credentials are changed.
This is made up of bits of security_bprm_apply_creds() and
security_bprm_post_apply_creds(), both of which have been removed.
This function is not allowed to fail; anything that might fail
must have been done in (c.ii).
(ii) Calls commit_creds() to apply the new credentials in a single
assignment (more or less). Possibly pdeath_signal and dumpable
should be part of struct creds.
(iii) Unlocks the task's cred_replace_mutex, thus allowing
PTRACE_ATTACH to take place.
(iv) Clears The bprm->cred pointer as the credentials it was holding
are now immutable.
(v) Calls security_bprm_committed_creds() to apply any security
alterations that must be done after the creds have been changed.
SELinux uses this to flush signals and signal handlers.
(f) If an error occurs before (d.i), bprm_free() will call abort_creds()
to destroy the proposed new credentials and will then unlock
cred_replace_mutex. No changes to the credentials will have been
made.
(2) LSM interface.
A number of functions have been changed, added or removed:
(*) security_bprm_alloc(), ->bprm_alloc_security()
(*) security_bprm_free(), ->bprm_free_security()
Removed in favour of preparing new credentials and modifying those.
(*) security_bprm_apply_creds(), ->bprm_apply_creds()
(*) security_bprm_post_apply_creds(), ->bprm_post_apply_creds()
Removed; split between security_bprm_set_creds(),
security_bprm_committing_creds() and security_bprm_committed_creds().
(*) security_bprm_set(), ->bprm_set_security()
Removed; folded into security_bprm_set_creds().
(*) security_bprm_set_creds(), ->bprm_set_creds()
New. The new credentials in bprm->creds should be checked and set up
as appropriate. bprm->cred_prepared is 0 on the first call, 1 on the
second and subsequent calls.
(*) security_bprm_committing_creds(), ->bprm_committing_creds()
(*) security_bprm_committed_creds(), ->bprm_committed_creds()
New. Apply the security effects of the new credentials. This
includes closing unauthorised files in SELinux. This function may not
fail. When the former is called, the creds haven't yet been applied
to the process; when the latter is called, they have.
The former may access bprm->cred, the latter may not.
(3) SELinux.
SELinux has a number of changes, in addition to those to support the LSM
interface changes mentioned above:
(a) The bprm_security_struct struct has been removed in favour of using
the credentials-under-construction approach.
(c) flush_unauthorized_files() now takes a cred pointer and passes it on
to inode_has_perm(), file_has_perm() and dentry_open().
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Inaugurate copy-on-write credentials management. This uses RCU to manage the
credentials pointer in the task_struct with respect to accesses by other tasks.
A process may only modify its own credentials, and so does not need locking to
access or modify its own credentials.
A mutex (cred_replace_mutex) is added to the task_struct to control the effect
of PTRACE_ATTACHED on credential calculations, particularly with respect to
execve().
With this patch, the contents of an active credentials struct may not be
changed directly; rather a new set of credentials must be prepared, modified
and committed using something like the following sequence of events:
struct cred *new = prepare_creds();
int ret = blah(new);
if (ret < 0) {
abort_creds(new);
return ret;
}
return commit_creds(new);
There are some exceptions to this rule: the keyrings pointed to by the active
credentials may be instantiated - keyrings violate the COW rule as managing
COW keyrings is tricky, given that it is possible for a task to directly alter
the keys in a keyring in use by another task.
To help enforce this, various pointers to sets of credentials, such as those in
the task_struct, are declared const. The purpose of this is compile-time
discouragement of altering credentials through those pointers. Once a set of
credentials has been made public through one of these pointers, it may not be
modified, except under special circumstances:
(1) Its reference count may incremented and decremented.
(2) The keyrings to which it points may be modified, but not replaced.
The only safe way to modify anything else is to create a replacement and commit
using the functions described in Documentation/credentials.txt (which will be
added by a later patch).
This patch and the preceding patches have been tested with the LTP SELinux
testsuite.
This patch makes several logical sets of alteration:
(1) execve().
This now prepares and commits credentials in various places in the
security code rather than altering the current creds directly.
(2) Temporary credential overrides.
do_coredump() and sys_faccessat() now prepare their own credentials and
temporarily override the ones currently on the acting thread, whilst
preventing interference from other threads by holding cred_replace_mutex
on the thread being dumped.
This will be replaced in a future patch by something that hands down the
credentials directly to the functions being called, rather than altering
the task's objective credentials.
(3) LSM interface.
A number of functions have been changed, added or removed:
(*) security_capset_check(), ->capset_check()
(*) security_capset_set(), ->capset_set()
Removed in favour of security_capset().
(*) security_capset(), ->capset()
New. This is passed a pointer to the new creds, a pointer to the old
creds and the proposed capability sets. It should fill in the new
creds or return an error. All pointers, barring the pointer to the
new creds, are now const.
(*) security_bprm_apply_creds(), ->bprm_apply_creds()
Changed; now returns a value, which will cause the process to be
killed if it's an error.
(*) security_task_alloc(), ->task_alloc_security()
Removed in favour of security_prepare_creds().
(*) security_cred_free(), ->cred_free()
New. Free security data attached to cred->security.
(*) security_prepare_creds(), ->cred_prepare()
New. Duplicate any security data attached to cred->security.
(*) security_commit_creds(), ->cred_commit()
New. Apply any security effects for the upcoming installation of new
security by commit_creds().
(*) security_task_post_setuid(), ->task_post_setuid()
Removed in favour of security_task_fix_setuid().
(*) security_task_fix_setuid(), ->task_fix_setuid()
Fix up the proposed new credentials for setuid(). This is used by
cap_set_fix_setuid() to implicitly adjust capabilities in line with
setuid() changes. Changes are made to the new credentials, rather
than the task itself as in security_task_post_setuid().
(*) security_task_reparent_to_init(), ->task_reparent_to_init()
Removed. Instead the task being reparented to init is referred
directly to init's credentials.
NOTE! This results in the loss of some state: SELinux's osid no
longer records the sid of the thread that forked it.
(*) security_key_alloc(), ->key_alloc()
(*) security_key_permission(), ->key_permission()
Changed. These now take cred pointers rather than task pointers to
refer to the security context.
(4) sys_capset().
This has been simplified and uses less locking. The LSM functions it
calls have been merged.
(5) reparent_to_kthreadd().
This gives the current thread the same credentials as init by simply using
commit_thread() to point that way.
(6) __sigqueue_alloc() and switch_uid()
__sigqueue_alloc() can't stop the target task from changing its creds
beneath it, so this function gets a reference to the currently applicable
user_struct which it then passes into the sigqueue struct it returns if
successful.
switch_uid() is now called from commit_creds(), and possibly should be
folded into that. commit_creds() should take care of protecting
__sigqueue_alloc().
(7) [sg]et[ug]id() and co and [sg]et_current_groups.
The set functions now all use prepare_creds(), commit_creds() and
abort_creds() to build and check a new set of credentials before applying
it.
security_task_set[ug]id() is called inside the prepared section. This
guarantees that nothing else will affect the creds until we've finished.
The calling of set_dumpable() has been moved into commit_creds().
Much of the functionality of set_user() has been moved into
commit_creds().
The get functions all simply access the data directly.
(8) security_task_prctl() and cap_task_prctl().
security_task_prctl() has been modified to return -ENOSYS if it doesn't
want to handle a function, or otherwise return the return value directly
rather than through an argument.
Additionally, cap_task_prctl() now prepares a new set of credentials, even
if it doesn't end up using it.
(9) Keyrings.
A number of changes have been made to the keyrings code:
(a) switch_uid_keyring(), copy_keys(), exit_keys() and suid_keys() have
all been dropped and built in to the credentials functions directly.
They may want separating out again later.
(b) key_alloc() and search_process_keyrings() now take a cred pointer
rather than a task pointer to specify the security context.
(c) copy_creds() gives a new thread within the same thread group a new
thread keyring if its parent had one, otherwise it discards the thread
keyring.
(d) The authorisation key now points directly to the credentials to extend
the search into rather pointing to the task that carries them.
(e) Installing thread, process or session keyrings causes a new set of
credentials to be created, even though it's not strictly necessary for
process or session keyrings (they're shared).
(10) Usermode helper.
The usermode helper code now carries a cred struct pointer in its
subprocess_info struct instead of a new session keyring pointer. This set
of credentials is derived from init_cred and installed on the new process
after it has been cloned.
call_usermodehelper_setup() allocates the new credentials and
call_usermodehelper_freeinfo() discards them if they haven't been used. A
special cred function (prepare_usermodeinfo_creds()) is provided
specifically for call_usermodehelper_setup() to call.
call_usermodehelper_setkeys() adjusts the credentials to sport the
supplied keyring as the new session keyring.
(11) SELinux.
SELinux has a number of changes, in addition to those to support the LSM
interface changes mentioned above:
(a) selinux_setprocattr() no longer does its check for whether the
current ptracer can access processes with the new SID inside the lock
that covers getting the ptracer's SID. Whilst this lock ensures that
the check is done with the ptracer pinned, the result is only valid
until the lock is released, so there's no point doing it inside the
lock.
(12) is_single_threaded().
This function has been extracted from selinux_setprocattr() and put into
a file of its own in the lib/ directory as join_session_keyring() now
wants to use it too.
The code in SELinux just checked to see whether a task shared mm_structs
with other tasks (CLONE_VM), but that isn't good enough. We really want
to know if they're part of the same thread group (CLONE_THREAD).
(13) nfsd.
The NFS server daemon now has to use the COW credentials to set the
credentials it is going to use. It really needs to pass the credentials
down to the functions it calls, but it can't do that until other patches
in this series have been applied.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: James Morris <jmorris@namei.org>
Pass credentials through dentry_open() so that the COW creds patch can have
SELinux's flush_unauthorized_files() pass the appropriate creds back to itself
when it opens its null chardev.
The security_dentry_open() call also now takes a creds pointer, as does the
dentry_open hook in struct security_operations.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: James Morris <jmorris@namei.org>
Make inode_has_perm() and file_has_perm() take a cred pointer rather than a
task pointer.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Wrap access to SELinux's task SID, using task_sid() and current_sid() as
appropriate.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: James Morris <jmorris@namei.org>
Use RCU to access another task's creds and to release a task's own creds.
This means that it will be possible for the credentials of a task to be
replaced without another task (a) requiring a full lock to read them, and (b)
seeing deallocated memory.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Wrap current->cred and a few other accessors to hide their actual
implementation.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Detach the credentials from task_struct, duplicating them in copy_process()
and releasing them in __put_task_struct().
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Separate the task security context from task_struct. At this point, the
security data is temporarily embedded in the task_struct with two pointers
pointing to it.
Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in
entry.S via asm-offsets.
With comment fixes Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Constify the kernel_cap_t arguments to the capset LSM hooks.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: James Morris <jmorris@namei.org>
Take away the ability for sys_capset() to affect processes other than current.
This means that current will not need to lock its own credentials when reading
them against interference by other processes.
This has effectively been the case for a while anyway, since:
(1) Without LSM enabled, sys_capset() is disallowed.
(2) With file-based capabilities, sys_capset() is neutered.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Andrew G. Morgan <morgan@kernel.org>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: James Morris <jmorris@namei.org>
check when determining if a process has additional powers to override
memory limits or when trying to read/write illegal file labels. Use
the new noaudit call instead.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
make an A or B type decision instead of a security decision. Currently
this is the case at least for filesystems when deciding if a process can use
the reserved 'root' blocks and for the case of things like the oom
algorithm determining if processes are root processes and should be less
likely to be killed. These types of security system requests should not be
audited or logged since they are not really security decisions. It would be
possible to solve this problem like the vm_enough_memory security check did
by creating a new LSM interface and moving all of the policy into that
interface but proves the needlessly bloat the LSM and provide complex
indirection.
This merely allows those decisions to be made where they belong and to not
flood logs or printk with denials for thing that are not security decisions.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Currently when SELinux has not been updated to handle a netlink message
type the operation is denied with EINVAL. This patch will leave the
audit/warning message so things get fixed but if policy chose to allow
unknowns this will allow the netlink operation.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
In enforcing mode '/sbin/ip addrlabel' results in a SELinux error:
type=SELINUX_ERR msg=audit(1225698822.073:42): SELinux: unrecognized
netlink message type=74 for sclass=43
The problem is missing RTM_*ADDRLABEL entries in SELinux's netlink
message types table.
Reported in https://bugzilla.redhat.com/show_bug.cgi?id=469423
Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
SELinux has long been calling wake_up_interruptible() on
current->parent->signal->wait_chldexit without holding any locks. It
appears that this operation should hold the tasklist_lock to dereference
current->parent and we should hold the siglock when waking up the
signal->wait_chldexit.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
SELinux has wrongly (since 2004) had an incorrect test for an empty
tty->tty_files list. With an empty list selinux would be pointing to part
of the tty struct itself and would then proceed to dereference that value
and again dereference that result. An F10 change to plymouth on a ppc64
system is actually currently triggering this bug. This patch uses
list_empty() to handle empty lists rather than looking at a meaningless
location.
[note, this fixes the oops reported in
https://bugzilla.redhat.com/show_bug.cgi?id=469079]
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Using NIPQUAD() with NIPQUAD_FMT, %d.%d.%d.%d or %u.%u.%u.%u
can be replaced with %pI4
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some operations, like searching a directory path or connecting a unix domain
socket, make explicit calls into inode_permission. Our choices are to
either try to come up with a signature for all of the explicit calls to
inode_permission and do not check open on those, or to move the open checks to
dentry_open where we know this is always an open operation. This patch moves
the checks to dentry_open.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
The iscsi_ibft.c changes are almost certainly a bugfix as the
pointer 'ip' is a u8 *, so they never print the last 8 bytes
of the IPv6 address, and the eight bytes they do print have
a zero byte with them in each 16-bit word.
Other than that, this should cause no difference in functionality.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a much better version of a previous patch to make the parser
tables constant. Rather than changing the typedef, we put the "const" in
all the various places where its required, allowing the __initconst
exception for nfsroot which was the cause of the previous trouble.
This was posted for review some time ago and I believe its been in -mm
since then.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Alexander Viro <aviro@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: (24 commits)
integrity: special fs magic
As pointed out by Jonathan Corbet, the timer must be deleted before
ERROR: code indent should use tabs where possible
The tpm_dev_release function is only called for platform devices, not pnp
Protect tpm_chip_list when transversing it.
Renames num_open to is_open, as only one process can open the file at a time.
Remove the BKL calls from the TPM driver, which were added in the overall
netlabel: Add configuration support for local labeling
cipso: Add support for native local labeling and fixup mapping names
netlabel: Changes to the NetLabel security attributes to allow LSMs to pass full contexts
selinux: Cache NetLabel secattrs in the socket's security struct
selinux: Set socket NetLabel based on connection endpoint
netlabel: Add functionality to set the security attributes of a packet
netlabel: Add network address selectors to the NetLabel/LSM domain mapping
netlabel: Add a generic way to create ordered linked lists of network addrs
netlabel: Replace protocol/NetLabel linking with refrerence counts
smack: Fix missing calls to netlbl_skbuff_err()
selinux: Fix missing calls to netlbl_skbuff_err()
selinux: Fix a problem in security_netlbl_sid_to_secattr()
selinux: Better local/forward check in selinux_ip_postroute()
...
Currently it is sometimes locked by the tty mutex and sometimes by the
sighand lock. The latter is in fact correct and now we can hand back referenced
objects we can fix this up without problems around sleeping functions.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We now return a kref covered tty reference. That ensures the tty structure
doesn't go away when you have a return from get_current_tty. This is not
enough to protect you from most of the resources being freed behind your
back - yet.
[Updated to include fixes for SELinux problems found by Andrew Morton and
an s390 leak found while debugging the former]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch provides support for including the LSM's secid in addition to
the LSM's MLS information in the NetLabel security attributes structure.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
Previous work enabled the use of address based NetLabel selectors, which
while highly useful, brought the potential for additional per-packet overhead
when used. This patch attempts to mitigate some of that overhead by caching
the NetLabel security attribute struct within the SELinux socket security
structure. This should help eliminate the need to recreate the NetLabel
secattr structure for each packet resulting in less overhead.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
Previous work enabled the use of address based NetLabel selectors, which while
highly useful, brought the potential for additional per-packet overhead when
used. This patch attempts to solve that by applying NetLabel socket labels
when sockets are connect()'d. This should alleviate the per-packet NetLabel
labeling for all connected sockets (yes, it even works for connected DGRAM
sockets).
Signed-off-by: Paul Moore <paul.moore@hp.com>
Reviewed-by: James Morris <jmorris@namei.org>
This patch builds upon the new NetLabel address selector functionality by
providing the NetLabel KAPI and CIPSO engine support needed to enable the
new packet-based labeling. The only new addition to the NetLabel KAPI at
this point is shown below:
* int netlbl_skbuff_setattr(skb, family, secattr)
... and is designed to be called from a Netfilter hook after the packet's
IP header has been populated such as in the FORWARD or LOCAL_OUT hooks.
This patch also provides the necessary SELinux hooks to support this new
functionality. Smack support is not currently included due to uncertainty
regarding the permissions needed to expand the Smack network access controls.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Reviewed-by: James Morris <jmorris@namei.org>
At some point I think I messed up and dropped the calls to netlbl_skbuff_err()
which are necessary for CIPSO to send error notifications to remote systems.
This patch re-introduces the error handling calls into the SELinux code.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
Currently when SELinux fails to allocate memory in
security_netlbl_sid_to_secattr() the NetLabel LSM domain field is set to
NULL which triggers the default NetLabel LSM domain mapping which may not
always be the desired mapping. This patch fixes this by returning an error
when the kernel is unable to allocate memory. This could result in more
failures on a system with heavy memory pressure but it is the "correct"
thing to do.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
It turns out that checking to see if skb->sk is NULL is not a very good
indicator of a forwarded packet as some locally generated packets also have
skb->sk set to NULL. Fix this by not only checking the skb->sk field but also
the IP[6]CB(skb)->flags field for the IP[6]SKB_FORWARDED flag. While we are
at it, we are calling selinux_parse_skb() much earlier than we really should
resulting in potentially wasted cycles parsing packets for information we
might no use; so shuffle the code around a bit to fix this.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
We did the right thing in a few cases but there were several areas where we
determined a packet's address family based on the socket's address family which
is not the right thing to do since we can get IPv4 packets on IPv6 sockets.
This patch fixes these problems by either taking the address family directly
from the packet.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
We were doing a lot of extra work in selinux_netlbl_sock_graft() what wasn't
necessary so this patch removes that code. It also removes the redundant
second argument to selinux_netlbl_sock_setsid() which allows us to simplify a
few other functions.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
At some point during the 2.6.27 development cycle two new fields were added
to the SELinux context structure, a string pointer and a length field. The
code in selinux_secattr_to_sid() was not modified and as a result these two
fields were left uninitialized which could result in erratic behavior,
including kernel panics, when NetLabel is used. This patch fixes the
problem by fully initializing the context in selinux_secattr_to_sid() before
use and reducing the level of direct context manipulation done to help
prevent future problems.
Please apply this to the 2.6.27-rcX release stream.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
At some point during the 2.6.27 development cycle two new fields were added
to the SELinux context structure, a string pointer and a length field. The
code in selinux_secattr_to_sid() was not modified and as a result these two
fields were left uninitialized which could result in erratic behavior,
including kernel panics, when NetLabel is used. This patch fixes the
problem by fully initializing the context in selinux_secattr_to_sid() before
use and reducing the level of direct context manipulation done to help
prevent future problems.
Please apply this to the 2.6.27-rcX release stream.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
As we are not concerned with fine-grained control over reading of
symlinks in proc, always use the default proc SID for all proc symlinks.
This should help avoid permission issues upon changes to the proc tree
as in the /proc/net -> /proc/self/net example.
This does not alter labeling of symlinks within /proc/pid directories.
ls -Zd /proc/net output before and after the patch should show the difference.
Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Overview
This patch reworks the handling of POSIX CPU timers, including the
ITIMER_PROF, ITIMER_VIRT timers and rlimit handling. It was put together
with the help of Roland McGrath, the owner and original writer of this code.
The problem we ran into, and the reason for this rework, has to do with using
a profiling timer in a process with a large number of threads. It appears
that the performance of the old implementation of run_posix_cpu_timers() was
at least O(n*3) (where "n" is the number of threads in a process) or worse.
Everything is fine with an increasing number of threads until the time taken
for that routine to run becomes the same as or greater than the tick time, at
which point things degrade rather quickly.
This patch fixes bug 9906, "Weird hang with NPTL and SIGPROF."
Code Changes
This rework corrects the implementation of run_posix_cpu_timers() to make it
run in constant time for a particular machine. (Performance may vary between
one machine and another depending upon whether the kernel is built as single-
or multiprocessor and, in the latter case, depending upon the number of
running processors.) To do this, at each tick we now update fields in
signal_struct as well as task_struct. The run_posix_cpu_timers() function
uses those fields to make its decisions.
We define a new structure, "task_cputime," to contain user, system and
scheduler times and use these in appropriate places:
struct task_cputime {
cputime_t utime;
cputime_t stime;
unsigned long long sum_exec_runtime;
};
This is included in the structure "thread_group_cputime," which is a new
substructure of signal_struct and which varies for uniprocessor versus
multiprocessor kernels. For uniprocessor kernels, it uses "task_cputime" as
a simple substructure, while for multiprocessor kernels it is a pointer:
struct thread_group_cputime {
struct task_cputime totals;
};
struct thread_group_cputime {
struct task_cputime *totals;
};
We also add a new task_cputime substructure directly to signal_struct, to
cache the earliest expiration of process-wide timers, and task_cputime also
replaces the it_*_expires fields of task_struct (used for earliest expiration
of thread timers). The "thread_group_cputime" structure contains process-wide
timers that are updated via account_user_time() and friends. In the non-SMP
case the structure is a simple aggregator; unfortunately in the SMP case that
simplicity was not achievable due to cache-line contention between CPUs (in
one measured case performance was actually _worse_ on a 16-cpu system than
the same test on a 4-cpu system, due to this contention). For SMP, the
thread_group_cputime counters are maintained as a per-cpu structure allocated
using alloc_percpu(). The timer functions update only the timer field in
the structure corresponding to the running CPU, obtained using per_cpu_ptr().
We define a set of inline functions in sched.h that we use to maintain the
thread_group_cputime structure and hide the differences between UP and SMP
implementations from the rest of the kernel. The thread_group_cputime_init()
function initializes the thread_group_cputime structure for the given task.
The thread_group_cputime_alloc() is a no-op for UP; for SMP it calls the
out-of-line function thread_group_cputime_alloc_smp() to allocate and fill
in the per-cpu structures and fields. The thread_group_cputime_free()
function, also a no-op for UP, in SMP frees the per-cpu structures. The
thread_group_cputime_clone_thread() function (also a UP no-op) for SMP calls
thread_group_cputime_alloc() if the per-cpu structures haven't yet been
allocated. The thread_group_cputime() function fills the task_cputime
structure it is passed with the contents of the thread_group_cputime fields;
in UP it's that simple but in SMP it must also safely check that tsk->signal
is non-NULL (if it is it just uses the appropriate fields of task_struct) and,
if so, sums the per-cpu values for each online CPU. Finally, the three
functions account_group_user_time(), account_group_system_time() and
account_group_exec_runtime() are used by timer functions to update the
respective fields of the thread_group_cputime structure.
Non-SMP operation is trivial and will not be mentioned further.
The per-cpu structure is always allocated when a task creates its first new
thread, via a call to thread_group_cputime_clone_thread() from copy_signal().
It is freed at process exit via a call to thread_group_cputime_free() from
cleanup_signal().
All functions that formerly summed utime/stime/sum_sched_runtime values from
from all threads in the thread group now use thread_group_cputime() to
snapshot the values in the thread_group_cputime structure or the values in
the task structure itself if the per-cpu structure hasn't been allocated.
Finally, the code in kernel/posix-cpu-timers.c has changed quite a bit.
The run_posix_cpu_timers() function has been split into a fast path and a
slow path; the former safely checks whether there are any expired thread
timers and, if not, just returns, while the slow path does the heavy lifting.
With the dedicated thread group fields, timers are no longer "rebalanced" and
the process_timer_rebalance() function and related code has gone away. All
summing loops are gone and all code that used them now uses the
thread_group_cputime() inline. When process-wide timers are set, the new
task_cputime structure in signal_struct is used to cache the earliest
expiration; this is checked in the fast path.
Performance
The fix appears not to add significant overhead to existing operations. It
generally performs the same as the current code except in two cases, one in
which it performs slightly worse (Case 5 below) and one in which it performs
very significantly better (Case 2 below). Overall it's a wash except in those
two cases.
I've since done somewhat more involved testing on a dual-core Opteron system.
Case 1: With no itimer running, for a test with 100,000 threads, the fixed
kernel took 1428.5 seconds, 513 seconds more than the unfixed system,
all of which was spent in the system. There were twice as many
voluntary context switches with the fix as without it.
Case 2: With an itimer running at .01 second ticks and 4000 threads (the most
an unmodified kernel can handle), the fixed kernel ran the test in
eight percent of the time (5.8 seconds as opposed to 70 seconds) and
had better tick accuracy (.012 seconds per tick as opposed to .023
seconds per tick).
Case 3: A 4000-thread test with an initial timer tick of .01 second and an
interval of 10,000 seconds (i.e. a timer that ticks only once) had
very nearly the same performance in both cases: 6.3 seconds elapsed
for the fixed kernel versus 5.5 seconds for the unfixed kernel.
With fewer threads (eight in these tests), the Case 1 test ran in essentially
the same time on both the modified and unmodified kernels (5.2 seconds versus
5.8 seconds). The Case 2 test ran in about the same time as well, 5.9 seconds
versus 5.4 seconds but again with much better tick accuracy, .013 seconds per
tick versus .025 seconds per tick for the unmodified kernel.
Since the fix affected the rlimit code, I also tested soft and hard CPU limits.
Case 4: With a hard CPU limit of 20 seconds and eight threads (and an itimer
running), the modified kernel was very slightly favored in that while
it killed the process in 19.997 seconds of CPU time (5.002 seconds of
wall time), only .003 seconds of that was system time, the rest was
user time. The unmodified kernel killed the process in 20.001 seconds
of CPU (5.014 seconds of wall time) of which .016 seconds was system
time. Really, though, the results were too close to call. The results
were essentially the same with no itimer running.
Case 5: With a soft limit of 20 seconds and a hard limit of 2000 seconds
(where the hard limit would never be reached) and an itimer running,
the modified kernel exhibited worse tick accuracy than the unmodified
kernel: .050 seconds/tick versus .028 seconds/tick. Otherwise,
performance was almost indistinguishable. With no itimer running this
test exhibited virtually identical behavior and times in both cases.
In times past I did some limited performance testing. those results are below.
On a four-cpu Opteron system without this fix, a sixteen-thread test executed
in 3569.991 seconds, of which user was 3568.435s and system was 1.556s. On
the same system with the fix, user and elapsed time were about the same, but
system time dropped to 0.007 seconds. Performance with eight, four and one
thread were comparable. Interestingly, the timer ticks with the fix seemed
more accurate: The sixteen-thread test with the fix received 149543 ticks
for 0.024 seconds per tick, while the same test without the fix received 58720
for 0.061 seconds per tick. Both cases were configured for an interval of
0.01 seconds. Again, the other tests were comparable. Each thread in this
test computed the primes up to 25,000,000.
I also did a test with a large number of threads, 100,000 threads, which is
impossible without the fix. In this case each thread computed the primes only
up to 10,000 (to make the runtime manageable). System time dominated, at
1546.968 seconds out of a total 2176.906 seconds (giving a user time of
629.938s). It received 147651 ticks for 0.015 seconds per tick, still quite
accurate. There is obviously no comparable test without the fix.
Signed-off-by: Frank Mayhar <fmayhar@google.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Update the SELinux entry in MAINTAINERS and drop the obsolete information
from the selinux Kconfig help text.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Fix a bug and a philosophical decision about who handles errors.
security_context_to_sid_core() was leaking a context in the common case.
This was causing problems on fedora systems which recently have started
making extensive use of this function.
In discussion it was decided that if string_to_context_struct() had an
error it was its own responsibility to clean up any mess it created
along the way.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
The purpose of this patch is to assign per-thread security context
under a constraint. It enables multi-threaded server application
to kick a request handler with its fair security context, and
helps some of userspace object managers to handle user's request.
When we assign a per-thread security context, it must not have wider
permissions than the original one. Because a multi-threaded process
shares a single local memory, an arbitary per-thread security context
also means another thread can easily refer violated information.
The constraint on a per-thread security context requires a new domain
has to be equal or weaker than its original one, when it tries to assign
a per-thread security context.
Bounds relationship between two types is a way to ensure a domain can
never have wider permission than its bounds. We can define it in two
explicit or implicit ways.
The first way is using new TYPEBOUNDS statement. It enables to define
a boundary of types explicitly. The other one expand the concept of
existing named based hierarchy. If we defines a type with "." separated
name like "httpd_t.php", toolchain implicitly set its bounds on "httpd_t".
This feature requires a new policy version.
The 24th version (POLICYDB_VERSION_BOUNDARY) enables to ship them into
kernel space, and the following patch enables to handle it.
Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Replace "thing != NULL" comparisons with just "thing" to make
the code look more uniform (mixed styles were used even in the
same source file).
Signed-off-by: Vesa-Matti Kari <vmkari@cc.helsinki.fi>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Fix the setting of PF_SUPERPRIV by __capable() as it could corrupt the flags
the target process if that is not the current process and it is trying to
change its own flags in a different way at the same time.
__capable() is using neither atomic ops nor locking to protect t->flags. This
patch removes __capable() and introduces has_capability() that doesn't set
PF_SUPERPRIV on the process being queried.
This patch further splits security_ptrace() in two:
(1) security_ptrace_may_access(). This passes judgement on whether one
process may access another only (PTRACE_MODE_ATTACH for ptrace() and
PTRACE_MODE_READ for /proc), and takes a pointer to the child process.
current is the parent.
(2) security_ptrace_traceme(). This passes judgement on PTRACE_TRACEME only,
and takes only a pointer to the parent process. current is the child.
In Smack and commoncap, this uses has_capability() to determine whether
the parent will be permitted to use PTRACE_ATTACH if normal checks fail.
This does not set PF_SUPERPRIV.
Two of the instances of __capable() actually only act on current, and so have
been changed to calls to capable().
Of the places that were using __capable():
(1) The OOM killer calls __capable() thrice when weighing the killability of a
process. All of these now use has_capability().
(2) cap_ptrace() and smack_ptrace() were using __capable() to check to see
whether the parent was allowed to trace any process. As mentioned above,
these have been split. For PTRACE_ATTACH and /proc, capable() is now
used, and for PTRACE_TRACEME, has_capability() is used.
(3) cap_safe_nice() only ever saw current, so now uses capable().
(4) smack_setprocattr() rejected accesses to tasks other than current just
after calling __capable(), so the order of these two tests have been
switched and capable() is used instead.
(5) In smack_file_send_sigiotask(), we need to allow privileged processes to
receive SIGIO on files they're manipulating.
(6) In smack_task_wait(), we let a process wait for a privileged process,
whether or not the process doing the waiting is privileged.
I've tested this with the LTP SELinux and syscalls testscripts.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: Andrew G. Morgan <morgan@kernel.org>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Morris <jmorris@namei.org>
expr_isvalid() in conditional.c was off-by-one and allowed
invalid expression type COND_LAST. However, it is this header file
that needs to be fixed. That way the if-statement's disjunction's
second component reads more naturally, "if expr type is greater than
the last allowed value" ( rather than using ">=" in conditional.c):
if (expr->expr_type <= 0 || expr->expr_type > COND_LAST)
Signed-off-by: Vesa-Matti Kari <vmkari@cc.helsinki.fi>
Signed-off-by: James Morris <jmorris@namei.org>
Fix a potentially uninitialised variable in SELinux hooks that's given a
pointer to the network address by selinux_parse_skb() passing a pointer back
through its argument list. By restructuring selinux_parse_skb(), the compiler
can see that the error case need not set it as the caller will return
immediately.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Trivial minor fixes that change C null character style.
Signed-off-by: Vesa-Matti Kari <vmkari@cc.helsinki.fi>
Signed-off-by: James Morris <jmorris@namei.org>
This patch makes the needlessly global selinux_write_opts() static.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: James Morris <jmorris@namei.org>
Given a hosed SELinux config in which a system never loads policy or
disables SELinux we currently just return -EINVAL for anyone trying to
read /proc/mounts. This is a configuration problem but we can certainly
be more graceful. This patch just ignores -EINVAL when displaying LSM
options and causes /proc/mounts display everything else it can. If
policy isn't loaded the obviously there are no options, so we aren't
really loosing any information here.
This is safe as the only other return of EINVAL comes from
security_sid_to_context_core() in the case of an invalid sid. Even if a
FS was mounted with a now invalidated context that sid should have been
remapped to unlabeled and so we won't hit the EINVAL and will work like
we should. (yes, I tested to make sure it worked like I thought)
Signed-off-by: Eric Paris <eparis@redhat.com>
Tested-by: Marc Dionne <marc.c.dionne@gmail.com>
Signed-off-by: James Morris <jmorris@namei.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (39 commits)
[PATCH] fix RLIM_NOFILE handling
[PATCH] get rid of corner case in dup3() entirely
[PATCH] remove remaining namei_{32,64}.h crap
[PATCH] get rid of indirect users of namei.h
[PATCH] get rid of __user_path_lookup_open
[PATCH] f_count may wrap around
[PATCH] dup3 fix
[PATCH] don't pass nameidata to __ncp_lookup_validate()
[PATCH] don't pass nameidata to gfs2_lookupi()
[PATCH] new (local) helper: user_path_parent()
[PATCH] sanitize __user_walk_fd() et.al.
[PATCH] preparation to __user_walk_fd cleanup
[PATCH] kill nameidata passing to permission(), rename to inode_permission()
[PATCH] take noexec checks to very few callers that care
Re: [PATCH 3/6] vfs: open_exec cleanup
[patch 4/4] vfs: immutable inode checking cleanup
[patch 3/4] fat: dont call notify_change
[patch 2/4] vfs: utimes cleanup
[patch 1/4] vfs: utimes: move owner check into inode_change_ok()
[PATCH] vfs: use kstrdup() and check failing allocation
...
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
netns: fix ip_rt_frag_needed rt_is_expired
netfilter: nf_conntrack_extend: avoid unnecessary "ct->ext" dereferences
netfilter: fix double-free and use-after free
netfilter: arptables in netns for real
netfilter: ip{,6}tables_security: fix future section mismatch
selinux: use nf_register_hooks()
netfilter: ebtables: use nf_register_hooks()
Revert "pkt_sched: sch_sfq: dump a real number of flows"
qeth: use dev->ml_priv instead of dev->priv
syncookies: Make sure ECN is disabled
net: drop unused BUG_TRAP()
net: convert BUG_TRAP to generic WARN_ON
drivers/net: convert BUG_TRAP to generic WARN_ON
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds the tracehook_tracer_task() hook to consolidate all forms of
"Who is using ptrace on me?" logic. This is used for "TracerPid:" in
/proc and for permission checks. We also clean up the selinux code the
called an identical accessor.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit 811f379927.
From Eric Paris:
"Please drop this patch for now. It deadlocks on ntfs-3g. I need to
rework it to handle fuse filesystems better. (casey was right)"
The register security hook is no longer required, as the capability
module is always registered. LSMs wishing to stack capability as
a secondary module should do so explicitly.
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
The sb_get_mnt_opts() hook is unused, and is superseded by the
sb_show_options() hook.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Acked-by: James Morris <jmorris@namei.org>
This patch causes SELinux mount options to show up in /proc/mounts. As
with other code in the area seq_put errors are ignored. Other LSM's
will not have their mount options displayed until they fill in their own
security_sb_show_options() function.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: James Morris <jmorris@namei.org>
Currently if a FS is mounted for which SELinux policy does not define an
fs_use_* that FS will either be genfs labeled or not labeled at all.
This decision is based on the existence of a genfscon rule in policy and
is irrespective of the capabilities of the filesystem itself. This
patch allows the kernel to check if the filesystem supports security
xattrs and if so will use those if there is no fs_use_* rule in policy.
An fstype with a no fs_use_* rule but with a genfs rule will use xattrs
if available and will follow the genfs rule.
This can be particularly interesting for things like ecryptfs which
actually overlays a real underlying FS. If we define excryptfs in
policy to use xattrs we will likely get this wrong at times, so with
this path we just don't need to define it!
Overlay ecryptfs on top of NFS with no xattr support:
SELinux: initialized (dev ecryptfs, type ecryptfs), uses genfs_contexts
Overlay ecryptfs on top of ext4 with xattr support:
SELinux: initialized (dev ecryptfs, type ecryptfs), uses xattr
It is also useful as the kernel adds new FS we don't need to add them in
policy if they support xattrs and that is how we want to handle them.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Use do_each_thread as a proper do/while block. Sparse complained.
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Remove unused and shadowed addrlen variable. Picked up by sparse.
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Paul Moore <paul.moore@hp.com>
I've gotten complaints and reports about people not understanding the
meaning of the current unknown class/perm handling the kernel emits on
every policy load. Hopefully this will make make it clear to everyone
the meaning of the message and won't waste a printk the user won't care
about anyway on systems where the kernel and the policy agree on
everything.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
On Mon, 2008-06-09 at 01:24 -0700, Andrew Morton wrote:
> Getting a few of these with FC5:
>
> SELinux: context_struct_compute_av: unrecognized class 69
> SELinux: context_struct_compute_av: unrecognized class 69
>
> one came out when I logged in.
>
> No other symptoms, yet.
Change handling of invalid classes by SELinux, reporting class values
unknown to the kernel as errors (w/ ratelimit applied) and handling
class values unknown to policy as normal denials.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
We used to protect against races of policy load in security_load_policy
by using the load_mutex. Since then we have added a new mutex,
sel_mutex, in sel_write_load() which is always held across all calls to
security_load_policy we are covered and can safely just drop this one.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
The class_to_string array is referenced by tclass. My code mistakenly
was using tclass - 1. If the proceeding class is a userspace class
rather than kernel class this may cause a denial/EINVAL even if unknown
handling is set to allow. The bug shouldn't be allowing excess
privileges since those are given based on the contents of another array
which should be correctly referenced.
At this point in time its pretty unlikely this is going to cause
problems. The most recently added kernel classes which could be
affected are association, dccp_socket, and peer. Its pretty unlikely
any policy with handle_unknown=allow doesn't have association and
dccp_socket undefined (they've been around longer than unknown handling)
and peer is conditionalized on a policy cap which should only be defined
if that class exists in policy.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Fix an endianness bug in the handling of network node addresses by
SELinux. This yields no change on little endian hardware but fixes
the incorrect handling on big endian hardware. The network node
addresses are stored in network order in memory by checkpolicy, not in
cpu/host order, and thus should not have cpu_to_le32/le32_to_cpu
conversions applied upon policy write/read unlike other data in the
policy.
Bug reported by John Weeks of Sun, who noticed that binary policy
files built from the same policy source on x86 and sparc differed and
tracked it down to the ipv4 address handling in checkpolicy.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Simplify and improve the robustness of the SELinux ioctl checking by
using the "access mode" bits of the ioctl command to determine the
permission check rather than dealing with individual command values.
This removes any knowledge of specific ioctl commands from SELinux
and follows the same guidance we gave to Smack earlier.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Enable processes with CAP_MAC_ADMIN + mac_admin permission in policy
to get undefined contexts on inodes. This extends the support for
deferred mapping of security contexts in order to permit restorecon
and similar programs to see the raw file contexts unknown to the
system policy in order to check them.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Enable security modules to distinguish reading of process state via
proc from full ptrace access by renaming ptrace_may_attach to
ptrace_may_access and adding a mode argument indicating whether only
read access or full attach access is requested. This allows security
modules to permit access to reading process state without granting
full ptrace access. The base DAC/capability checking remains unchanged.
Read access to /proc/pid/mem continues to apply a full ptrace attach
check since check_mem_permission() already requires the current task
to already be ptracing the target. The other ptrace checks within
proc for elements like environ, maps, and fds are changed to pass the
read mode instead of attach.
In the SELinux case, we model such reading of process state as a
reading of a proc file labeled with the target process' label. This
enables SELinux policy to permit such reading of process state without
permitting control or manipulation of the target process, as there are
a number of cases where programs probe for such information via proc
but do not need to be able to control the target (e.g. procps,
lsof, PolicyKit, ConsoleKit). At present we have to choose between
allowing full ptrace in policy (more permissive than required/desired)
or breaking functionality (or in some cases just silencing the denials
via dontaudit rules but this can hide genuine attacks).
This version of the patch incorporates comments from Casey Schaufler
(change/replace existing ptrace_may_attach interface, pass access
mode), and Chris Wright (provide greater consistency in the checking).
Note that like their predecessors __ptrace_may_attach and
ptrace_may_attach, the __ptrace_may_access and ptrace_may_access
interfaces use different return value conventions from each other (0
or -errno vs. 1 or 0). I retained this difference to avoid any
changes to the caller logic but made the difference clearer by
changing the latter interface to return a bool rather than an int and
by adding a comment about it to ptrace.h for any future callers.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: James Morris <jmorris@namei.org>
Remove inherit field from inode_security_struct, per Stephen Smalley:
"Let's just drop inherit altogether - dead field."
Signed-off-by: James Morris <jmorris@namei.org>
reorder inode_security_struct to remove padding on 64 bit builds
size reduced from 72 to 64 bytes increasing objects per slab to 64.
Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk>
Signed-off-by: James Morris <jmorris@namei.org>
Formatting and syntax changes
whitespace, tabs to spaces, trailing space
put open { on same line as struct def
remove unneeded {} after if statements
change printk("Lu") to printk("llu")
convert asm/uaccess.h to linux/uaacess.h includes
remove unnecessary asm/bug.h includes
convert all users of simple_strtol to strict_strtol
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Fix a sleeping function called from invalid context bug by moving allocation
to the callers prior to taking the policy rdlock.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Introduce SELinux support for deferred mapping of security contexts in
the SID table upon policy reload, and use this support for inode
security contexts when the context is not yet valid under the current
policy. Only processes with CAP_MAC_ADMIN + mac_admin permission in
policy can set undefined security contexts on inodes. Inodes with
such undefined contexts are treated as having the unlabeled context
until the context becomes valid upon a policy reload that defines the
context. Context invalidation upon policy reload also uses this
support to save the context information in the SID table and later
recover it upon a subsequent policy reload that defines the context
again.
This support is to enable package managers and similar programs to set
down file contexts unknown to the system policy at the time the file
is created in order to better support placing loadable policy modules
in packages and to support build systems that need to create images of
different distro releases with different policies w/o requiring all of
the contexts to be defined or legal in the build host policy.
With this patch applied, the following sequence is possible, although
in practice it is recommended that this permission only be allowed to
specific program domains such as the package manager.
# rmdir baz
# rm bar
# touch bar
# chcon -t foo_exec_t bar # foo_exec_t is not yet defined
chcon: failed to change context of `bar' to `system_u:object_r:foo_exec_t': Invalid argument
# mkdir -Z system_u:object_r:foo_exec_t baz
mkdir: failed to set default file creation context to `system_u:object_r:foo_exec_t': Invalid argument
# cat setundefined.te
policy_module(setundefined, 1.0)
require {
type unconfined_t;
type unlabeled_t;
}
files_type(unlabeled_t)
allow unconfined_t self:capability2 mac_admin;
# make -f /usr/share/selinux/devel/Makefile setundefined.pp
# semodule -i setundefined.pp
# chcon -t foo_exec_t bar # foo_exec_t is not yet defined
# mkdir -Z system_u:object_r:foo_exec_t baz
# ls -Zd bar baz
-rw-r--r-- root root system_u:object_r:unlabeled_t bar
drwxr-xr-x root root system_u:object_r:unlabeled_t baz
# cat foo.te
policy_module(foo, 1.0)
type foo_exec_t;
files_type(foo_exec_t)
# make -f /usr/share/selinux/devel/Makefile foo.pp
# semodule -i foo.pp # defines foo_exec_t
# ls -Zd bar baz
-rw-r--r-- root root user_u:object_r:foo_exec_t bar
drwxr-xr-x root root system_u:object_r:foo_exec_t baz
# semodule -r foo
# ls -Zd bar baz
-rw-r--r-- root root system_u:object_r:unlabeled_t bar
drwxr-xr-x root root system_u:object_r:unlabeled_t baz
# semodule -i foo.pp
# ls -Zd bar baz
-rw-r--r-- root root user_u:object_r:foo_exec_t bar
drwxr-xr-x root root system_u:object_r:foo_exec_t baz
# semodule -r setundefined foo
# chcon -t foo_exec_t bar # no longer defined and not allowed
chcon: failed to change context of `bar' to `system_u:object_r:foo_exec_t': Invalid argument
# rmdir baz
# mkdir -Z system_u:object_r:foo_exec_t baz
mkdir: failed to set default file creation context to `system_u:object_r:foo_exec_t': Invalid argument
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Every implementation of ->task_kill() does nothing when the signal comes from
the kernel. This is correct, but means that check_kill_permission() should
call security_task_kill() only for SI_FROMUSER() case, and we can remove the
same check from ->task_kill() implementations.
(sadly, check_kill_permission() is the last user of signal->session/__session
but we can't s/task_session_nr/task_session/ here).
NOTE: Eric W. Biederman pointed out cap_task_kill() should die, and I think
he is very right.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: David Quigley <dpquigl@tycho.nsa.gov>
Cc: Eric Paris <eparis@redhat.com>
Cc: Harald Welte <laforge@gnumonks.org>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make secctx_to_secid() take constant secdata.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'audit.b50' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current:
[PATCH] new predicate - AUDIT_FILETYPE
[patch 2/2] Use find_task_by_vpid in audit code
[patch 1/2] audit: let userspace fully control TTY input auditing
[PATCH 2/2] audit: fix sparse shadowed variable warnings
[PATCH 1/2] audit: move extern declarations to audit.h
Audit: MAINTAINERS update
Audit: increase the maximum length of the key field
Audit: standardize string audit interfaces
Audit: stop deadlock from signals under load
Audit: save audit_backlog_limit audit messages in case auditd comes back
Audit: collect sessionid in netlink messages
Audit: end printk with newline
Don't generate the per-UID user and user session keyrings unless they're
explicitly accessed. This solves a problem during a login process whereby
set*uid() is called before the SELinux PAM module, resulting in the per-UID
keyrings having the wrong security labels.
This also cures the problem of multiple per-UID keyrings sometimes appearing
due to PAM modules (including pam_keyinit) setuiding and causing user_structs
to come into and go out of existence whilst the session keyring pins the user
keyring. This is achieved by first searching for extant per-UID keyrings
before inventing new ones.
The serial bound argument is also dropped from find_keyring_by_name() as it's
not currently made use of (setting it to 0 disables the feature).
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: <kwc@citi.umich.edu>
Cc: <arunsr@cse.iitk.ac.in>
Cc: <dwalsh@redhat.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a keyctl() function to get the security label of a key.
The following is added to Documentation/keys.txt:
(*) Get the LSM security context attached to a key.
long keyctl(KEYCTL_GET_SECURITY, key_serial_t key, char *buffer,
size_t buflen)
This function returns a string that represents the LSM security context
attached to a key in the buffer provided.
Unless there's an error, it always returns the amount of data it could
produce, even if that's too big for the buffer, but it won't copy more
than requested to userspace. If the buffer pointer is NULL then no copy
will take place.
A NUL character is included at the end of the string if the buffer is
sufficiently big. This is included in the returned count. If no LSM is
in force then an empty string will be returned.
A process must have view permission on the key for this function to be
successful.
[akpm@linux-foundation.org: declare keyctl_get_security()]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add missing consts to xattr function arguments.
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/selinux-2.6:
SELinux: Fix a RCU free problem with the netport cache
SELinux: Made netnode cache adds faster
SELinux: include/security.h whitespace, syntax, and other cleanups
SELinux: policydb.h whitespace, syntax, and other cleanups
SELinux: mls_types.h whitespace, syntax, and other cleanups
SELinux: mls.h whitespace, syntax, and other cleanups
SELinux: hashtab.h whitespace, syntax, and other cleanups
SELinux: context.h whitespace, syntax, and other cleanups
SELinux: ss/conditional.h whitespace, syntax, and other cleanups
SELinux: selinux/include/security.h whitespace, syntax, and other cleanups
SELinux: objsec.h whitespace, syntax, and other cleanups
SELinux: netlabel.h whitespace, syntax, and other cleanups
SELinux: avc_ss.h whitespace, syntax, and other cleanups
Fixed up conflict in include/linux/security.h manually
Filesystem capability support makes it possible to do away with (set)uid-0
based privilege and use capabilities instead. That is, with filesystem
support for capabilities but without this present patch, it is (conceptually)
possible to manage a system with capabilities alone and never need to obtain
privilege via (set)uid-0.
Of course, conceptually isn't quite the same as currently possible since few
user applications, certainly not enough to run a viable system, are currently
prepared to leverage capabilities to exercise privilege. Further, many
applications exist that may never get upgraded in this way, and the kernel
will continue to want to support their setuid-0 base privilege needs.
Where pure-capability applications evolve and replace setuid-0 binaries, it is
desirable that there be a mechanisms by which they can contain their
privilege. In addition to leveraging the per-process bounding and inheritable
sets, this should include suppressing the privilege of the uid-0 superuser
from the process' tree of children.
The feature added by this patch can be leveraged to suppress the privilege
associated with (set)uid-0. This suppression requires CAP_SETPCAP to
initiate, and only immediately affects the 'current' process (it is inherited
through fork()/exec()). This reimplementation differs significantly from the
historical support for securebits which was system-wide, unwieldy and which
has ultimately withered to a dead relic in the source of the modern kernel.
With this patch applied a process, that is capable(CAP_SETPCAP), can now drop
all legacy privilege (through uid=0) for itself and all subsequently
fork()'d/exec()'d children with:
prctl(PR_SET_SECUREBITS, 0x2f);
This patch represents a no-op unless CONFIG_SECURITY_FILE_CAPABILITIES is
enabled at configure time.
[akpm@linux-foundation.org: fix uninitialised var warning]
[serue@us.ibm.com: capabilities: use cap_task_prctl when !CONFIG_SECURITY]
Signed-off-by: Andrew G. Morgan <morgan@kernel.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Reviewed-by: James Morris <jmorris@namei.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Paul Moore <paul.moore@hp.com>
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch standardized the string auditing interfaces. No userspace
changes will be visible and this is all just cleanup and consistancy
work. We have the following string audit interfaces to use:
void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf, size_t len);
void audit_log_n_string(struct audit_buffer *ab, const char *buf, size_t n);
void audit_log_string(struct audit_buffer *ab, const char *buf);
void audit_log_n_untrustedstring(struct audit_buffer *ab, const char *string, size_t n);
void audit_log_untrustedstring(struct audit_buffer *ab, const char *string);
This may be the first step to possibly fixing some of the issues that
people have with the string output from the kernel audit system. But we
still don't have an agreed upon solution to that problem.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The netport cache doesn't free resources in a manner which is safe or orderly.
This patch fixes this by adding in a missing call to rcu_dereference() in
sel_netport_insert() as well as some general cleanup throughout the file.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
When adding new entries to the network node cache we would walk the entire
hash bucket to make sure we didn't cross a threshold (done to bound the
cache size). This isn't a very quick or elegant solution for something
which is supposed to be quick-ish so add a counter to each hash bucket to
track the size of the bucket and eliminate the need to walk the entire
bucket list on each add.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes policydb.h to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
spaces followed by tabs
spaces used instead of tabs
location of * in pointer declarations
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes mls_types.h to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
spaces used instead of tabs
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes mls.h to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
spaces used instead of tabs
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes hashtab.h to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
spaces used instead of tabs
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes context.h to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
include spaces around , in function calls
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes ss/conditional.h to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
location of * in pointer declarations
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes selinux/include/security.h to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
location of { around structs and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
no assignments in if statements
and any number of other things I forgot to mention
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes objsec.h to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
location of { around structs and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
no assignments in if statements
and any number of other things I forgot to mention
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes netlabel.h to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
spaces used instead of tabs
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes avc_ss.h to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
location of { around structs and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
no assignments in if statements
and any number of other things I forgot to mention
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
[PATCH] get rid of __exit_files(), __exit_fs() and __put_fs_struct()
[PATCH] proc_readfd_common() race fix
[PATCH] double-free of inode on alloc_file() failure exit in create_write_pipe()
[PATCH] teach seq_file to discard entries
[PATCH] umount_tree() will unhash everything itself
[PATCH] get rid of more nameidata passing in namespace.c
[PATCH] switch a bunch of LSM hooks from nameidata to path
[PATCH] lock exclusively in collect_mounts() and drop_collected_mounts()
[PATCH] move a bunch of declarations to fs/internal.h
The attached patch needs to move from -rt to mainline given preemptable RCU.
This patch fixes SELinux code that implicitly assumes that disabling
preemption prevents an RCU grace period from completing, an assumption that
is valid for Classic RCU, but not necessarily for preemptable RCU. Explicit
rcu_read_lock() calls are thus added.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
The Fedora installer actually makes multiple NFS mounts before it loads
selinux policy. The code in selinux_clone_mnt_opts() assumed that the
init process would always be loading policy before NFS was up and
running. It might be possible to hit this in a diskless environment as
well, I'm not sure. There is no need to BUG_ON() in this situation
since we can safely continue given the circumstances.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
avc.c was bad. It had whitespace and syntax issues which are against
our coding style. I have had a little chat with it and the result of
that conversation looked like this patch.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Why would anyone just clean up white space all day? Because they were
out too late last night and don't want to think for a day. So here is a
nice clean selinuxfs.c patch.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
More formatting changes. Aside from the 80 character line limit even
the checkpatch scripts like this file now. Too bad I don't get paid by
the lines of code I change.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
All whitespace and formatting. Nothing interesting to see here. About
the only thing to remember is that we aren't supposed to initialize
static variables to 0/NULL. It is done for us and doing it ourselves
puts them in a different section.
With this patch running checkpatch.pl against hooks.c only gives us
complaints about busting the 80 character limit and declaring extern's
in .c files. Apparently they don't like it, but I don't feel like going
to the trouble of moving those to .h files...
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Make sure all printk start with KERN_*
Make sure all printk end with \n
Make sure all printk have the word 'selinux' in them
Change "function name" to "%s", __func__ (found 2 wrong)
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes sidtab.c to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
locateion of { around struct and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
and any number of other things I forgot to mention
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes services.c to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
locateion of { around struct and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
and any number of other things I forgot to mention
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes mls.c to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
locateion of { around struct and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
and any number of other things I forgot to mention
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes hashtab.c to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
locateion of { around struct and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
and any number of other things I forgot to mention
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes ebitmap.c to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
locateion of { around struct and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
and any number of other things I forgot to mention
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes conditional.c to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
locateion of { around struct and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
and any number of other things I forgot to mention
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes avtab.c to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
locateion of { around struct and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
and any number of other things I forgot to mention
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes xfrm.c to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
locateion of { around struct and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
and any number of other things I forgot to mention
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes nlmsgtab.c to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
locateion of { around struct and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
and any number of other things I forgot to mention
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch changes netnode.c to fix whitespace and syntax issues. Things that
are fixed may include (does not not have to include)
whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
locateion of { around struct and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
and any number of other things I forgot to mention
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
