android_kernel_google_msm/security
David Howells e9fb8c3832 KEYS: Perform RCU synchronisation on keys prior to key destruction
Make the keys garbage collector invoke synchronize_rcu() prior to destroying
keys with a zero usage count.  This means that a key can be examined under the
RCU read lock in the safe knowledge that it won't get deallocated until after
the lock is released - even if its usage count becomes zero whilst we're
looking at it.

This is useful in keyring search vs key link.  Consider a keyring containing a
link to a key.  That link can be replaced in-place in the keyring without
requiring an RCU copy-and-replace on the keyring contents without breaking a
search underway on that keyring when the displaced key is released, provided
the key is actually destroyed only after the RCU read lock held by the search
algorithm is released.

This permits __key_link() to replace a key without having to reallocate the key
payload.  A key gets replaced if a new key being linked into a keyring has the
same type and description.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>

Change-Id: Ifd8549b5b906c638d63c358ce1f34acd81139207
2016-10-29 23:12:11 +08:00
..
apparmor nick kvfree() from apparmor 2014-11-18 15:13:23 -08:00
integrity security: fix ima kconfig warning 2012-02-28 11:01:15 +11:00
keys KEYS: Perform RCU synchronisation on keys prior to key destruction 2016-10-29 23:12:11 +08:00
selinux consitify do_mount() arguments 2015-07-13 11:17:52 -07:00
smack consitify do_mount() arguments 2015-07-13 11:17:52 -07:00
tomoyo consitify do_mount() arguments 2015-07-13 11:17:52 -07:00
yama Yama: add PR_SET_PTRACER_ANY 2012-02-16 10:25:18 +11:00
capability.c consitify do_mount() arguments 2015-07-13 11:17:52 -07:00
commoncap.c Add PR_{GET,SET}_NO_NEW_PRIVS to prevent execve from granting privs 2014-10-31 19:46:07 -07:00
device_cgroup.c cgroup: remove cgroup_subsys argument from callbacks 2012-02-02 09:20:22 -08:00
inode.c securityfs: fix object creation races 2012-01-10 10:20:35 -05:00
Kconfig FROMLIST: security,perf: Allow further restriction of perf_event_open 2016-06-20 19:00:29 +00:00
lsm_audit.c security: lsm_audit: add ioctl specific auditing 2015-04-20 09:42:31 -07:00
Makefile security: Yama LSM 2012-02-10 09:18:52 +11:00
min_addr.c mmap_min_addr check CAP_SYS_RAWIO only for write 2010-04-23 08:56:31 +10:00
security.c consitify do_mount() arguments 2015-07-13 11:17:52 -07:00