Commit Graph

1881 Commits

Author SHA1 Message Date
Will Deacon 132a90cc77 asm-generic: add memfd_create system call to unistd.h
Commit 9183df25fe7b ("shm: add memfd_create() syscall") added a new
system call (memfd_create) but didn't update the asm-generic unistd
header.

This patch adds the new system call to the asm-generic version of
unistd.h so that it can be used by architectures such as arm64.

Change-Id: Iae81f47dfff775ccb1fb8187a59ceb160e623865
Cc: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2020-10-08 05:52:37 -07:00
David Herrmann d26af5a68d shm: add sealing API
If two processes share a common memory region, they usually want some
guarantees to allow safe access. This often includes:
  - one side cannot overwrite data while the other reads it
  - one side cannot shrink the buffer while the other accesses it
  - one side cannot grow the buffer beyond previously set boundaries

If there is a trust-relationship between both parties, there is no need
for policy enforcement.  However, if there's no trust relationship (eg.,
for general-purpose IPC) sharing memory-regions is highly fragile and
often not possible without local copies.  Look at the following two
use-cases:

  1) A graphics client wants to share its rendering-buffer with a
     graphics-server. The memory-region is allocated by the client for
     read/write access and a second FD is passed to the server. While
     scanning out from the memory region, the server has no guarantee that
     the client doesn't shrink the buffer at any time, requiring rather
     cumbersome SIGBUS handling.
  2) A process wants to perform an RPC on another process. To avoid huge
     bandwidth consumption, zero-copy is preferred. After a message is
     assembled in-memory and a FD is passed to the remote side, both sides
     want to be sure that neither modifies this shared copy, anymore. The
     source may have put sensible data into the message without a separate
     copy and the target may want to parse the message inline, to avoid a
     local copy.

While SIGBUS handling, POSIX mandatory locking and MAP_DENYWRITE provide
ways to achieve most of this, the first one is unproportionally ugly to
use in libraries and the latter two are broken/racy or even disabled due
to denial of service attacks.

This patch introduces the concept of SEALING.  If you seal a file, a
specific set of operations is blocked on that file forever.  Unlike locks,
seals can only be set, never removed.  Hence, once you verified a specific
set of seals is set, you're guaranteed that no-one can perform the blocked
operations on this file, anymore.

An initial set of SEALS is introduced by this patch:
  - SHRINK: If SEAL_SHRINK is set, the file in question cannot be reduced
            in size. This affects ftruncate() and open(O_TRUNC).
  - GROW: If SEAL_GROW is set, the file in question cannot be increased
          in size. This affects ftruncate(), fallocate() and write().
  - WRITE: If SEAL_WRITE is set, no write operations (besides resizing)
           are possible. This affects fallocate(PUNCH_HOLE), mmap() and
           write().
  - SEAL: If SEAL_SEAL is set, no further seals can be added to a file.
          This basically prevents the F_ADD_SEAL operation on a file and
          can be set to prevent others from adding further seals that you
          don't want.

The described use-cases can easily use these seals to provide safe use
without any trust-relationship:

  1) The graphics server can verify that a passed file-descriptor has
     SEAL_SHRINK set. This allows safe scanout, while the client is
     allowed to increase buffer size for window-resizing on-the-fly.
     Concurrent writes are explicitly allowed.
  2) For general-purpose IPC, both processes can verify that SEAL_SHRINK,
     SEAL_GROW and SEAL_WRITE are set. This guarantees that neither
     process can modify the data while the other side parses it.
     Furthermore, it guarantees that even with writable FDs passed to the
     peer, it cannot increase the size to hit memory-limits of the source
     process (in case the file-storage is accounted to the source).

The new API is an extension to fcntl(), adding two new commands:
  F_GET_SEALS: Return a bitset describing the seals on the file. This
               can be called on any FD if the underlying file supports
               sealing.
  F_ADD_SEALS: Change the seals of a given file. This requires WRITE
               access to the file and F_SEAL_SEAL may not already be set.
               Furthermore, the underlying file must support sealing and
               there may not be any existing shared mapping of that file.
               Otherwise, EBADF/EPERM is returned.
               The given seals are _added_ to the existing set of seals
               on the file. You cannot remove seals again.

The fcntl() handler is currently specific to shmem and disabled on all
files. A file needs to explicitly support sealing for this interface to
work. A separate syscall is added in a follow-up, which creates files that
support sealing. There is no intention to support this on other
file-systems. Semantics are unclear for non-volatile files and we lack any
use-case right now. Therefore, the implementation is specific to shmem.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Angelo G. Del Regno <kholk11@gmail.com>
2020-10-08 05:52:37 -07:00
David Herrmann 10f3a4935d shm: add memfd_create() syscall
memfd_create() is similar to mmap(MAP_ANON), but returns a file-descriptor
that you can pass to mmap().  It can support sealing and avoids any
connection to user-visible mount-points.  Thus, it's not subject to quotas
on mounted file-systems, but can be used like malloc()'ed memory, but with
a file-descriptor to it.

memfd_create() returns the raw shmem file, so calls like ftruncate() can
be used to modify the underlying inode.  Also calls like fstat() will
return proper information and mark the file as regular file.  If you want
sealing, you can specify MFD_ALLOW_SEALING.  Otherwise, sealing is not
supported (like on all other regular files).

Compared to O_TMPFILE, it does not require a tmpfs mount-point and is not
subject to a filesystem size limit.  It is still properly accounted to
memcg limits, though, and to the same overcommit or no-overcommit
accounting as all user memory.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Angelo G. Del Regno <kholk11@gmail.com>
2020-10-08 05:52:36 -07:00
Johannes Berg 0dad032b69 ipv4: add option to drop gratuitous ARP packets
In certain 802.11 wireless deployments, there will be ARP proxies
that use knowledge of the network to correctly answer requests.
To prevent gratuitous ARP frames on the shared medium from being
a problem, on such deployments wireless needs to drop them.

Enable this by providing an option called "drop_gratuitous_arp".

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 4078228159c9f54cca7347a8bdace29f2abdef65)

Change-Id: I8772dbd7471085878f8b4161eb2a056d79b8b232
2019-08-03 00:23:56 +02:00
Johannes Berg 98f1b6eb4e ipv4: add option to drop unicast encapsulated in L2 multicast
In order to solve a problem with 802.11, the so-called hole-196 attack,
add an option (sysctl) called "drop_unicast_in_l2_multicast" which, if
enabled, causes the stack to drop IPv4 unicast packets encapsulated in
link-layer multi- or broadcast frames. Such frames can (as an attack)
be created by any member of the same wireless network and transmitted
as valid encrypted frames since the symmetric key for broadcast frames
is shared between all stations.

Additionally, enabling this option provides compliance with a SHOULD
clause of RFC 1122.

Change-Id: I8de9fa5bdbea0556802f2ee553d0e73c1349213e
Reviewed-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-03 00:23:48 +02:00
stephen hemminger 7033bf1d6b ipv4: expose IPV4_DEVCONF
IP sends device configuration (see inet_fill_link_af) as an array
in the netlink information, but the indices in that array are not
exposed to userspace through any current santized header file.

It was available back in 2.6.32 (in /usr/include/linux/sysctl.h)
but was broken by:
  commit 02291680ff
  Author: Eric W. Biederman <ebiederm@xmission.com>
  Date:   Sun Feb 14 03:25:51 2010 +0000

    net ipv4: Decouple ipv4 interface parameters from binary sysctl numbers

Eric was solving the sysctl problem but then the indices were re-exposed
by a later addition of devconf support for IPV4

  commit 9f0f7272ac
  Author: Thomas Graf <tgraf@infradead.org>
  Date:   Tue Nov 16 04:32:48 2010 +0000

    ipv4: AF_INET link address family

Putting them in /usr/include/linux/ip.h seemed the logical match
for the DEVCONF_ definitions for IPV6 in /usr/include/linux/ip6.h

Change-Id: I082d6801e5677507ed2f2a25562fc4195f59c4e4
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-03 00:23:38 +02:00
Eric Dumazet b0494cd73f tcp: tcp_fragment() should apply sane memory limits
commit f070ef2ac66716357066b683fb0baf55f8191a2e upstream.

Jonathan Looney reported that a malicious peer can force a sender
to fragment its retransmit queue into tiny skbs, inflating memory
usage and/or overflow 32bit counters.

TCP allows an application to queue up to sk_sndbuf bytes,
so we need to give some allowance for non malicious splitting
of retransmit queue.

A new SNMP counter is added to monitor how many times TCP
did not allow to split an skb if the allowance was exceeded.

Note that this counter might increase in the case applications
use SO_SNDBUF socket option to lower sk_sndbuf.

CVE-2019-11478 : tcp_fragment, prevent fragmenting a packet when the
	socket is already using more than half the allowed space

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jonathan Looney <jtl@netflix.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
Cc: Bruce Curtis <brucec@netflix.com>
Cc: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-27 22:11:09 +02:00
Daniel Borkmann 8d9f2b4367 netfilter: nf_nat: add full port randomization support
We currently use prandom_u32() for allocation of ports in tcp bind(0)
and udp code. In case of plain SNAT we try to keep the ports as is
or increment on collision.

SNAT --random mode does use per-destination incrementing port
allocation. As a recent paper pointed out in [1] that this mode of
port allocation makes it possible to an attacker to find the randomly
allocated ports through a timing side-channel in a socket overloading
attack conducted through an off-path attacker.

So, NF_NAT_RANGE_PROTO_RANDOM actually weakens the port randomization
in regard to the attack described in this paper. As we need to keep
compatibility, add another flag called NF_NAT_RANGE_PROTO_RANDOM_FULLY
that would replace the NF_NAT_RANGE_PROTO_RANDOM hash-based port
selection algorithm with a simple prandom_u32() in order to mitigate
this attack vector. Note that the lfsr113's internal state is
periodically reseeded by the kernel through a local secure entropy
source.

More details can be found in [1], the basic idea is to send bursts
of packets to a socket to overflow its receive queue and measure
the latency to detect a possible retransmit when the port is found.
Because of increasing ports to given destination and port, further
allocations can be predicted. This information could then be used by
an attacker for e.g. for cache-poisoning, NS pinning, and degradation
of service attacks against DNS servers [1]:

  The best defense against the poisoning attacks is to properly
  deploy and validate DNSSEC; DNSSEC provides security not only
  against off-path attacker but even against MitM attacker. We hope
  that our results will help motivate administrators to adopt DNSSEC.
  However, full DNSSEC deployment make take significant time, and
  until that happens, we recommend short-term, non-cryptographic
  defenses. We recommend to support full port randomisation,
  according to practices recommended in [2], and to avoid
  per-destination sequential port allocation, which we show may be
  vulnerable to derandomisation attacks.

Joint work between Hannes Frederic Sowa and Daniel Borkmann.

 [1] https://sites.google.com/site/hayashulman/files/NIC-derandomisation.pdf
 [2] http://arxiv.org/pdf/1205.5190v1.pdf

Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-07-27 22:08:25 +02:00
Eric Biggers 9d142346b2 ppp: remove the PPPIOCDETACH ioctl
commit af8d3c7c001ae7df1ed2b2715f058113efc86187 upstream.

The PPPIOCDETACH ioctl effectively tries to "close" the given ppp file
before f_count has reached 0, which is fundamentally a bad idea.  It
does check 'f_count < 2', which excludes concurrent operations on the
file since they would only be possible with a shared fd table, in which
case each fdget() would take a file reference.  However, it fails to
account for the fact that even with 'f_count == 1' the file can still be
linked into epoll instances.  As reported by syzbot, this can trivially
be used to cause a use-after-free.

Yet, the only known user of PPPIOCDETACH is pppd versions older than
ppp-2.4.2, which was released almost 15 years ago (November 2003).
Also, PPPIOCDETACH apparently stopped working reliably at around the
same time, when the f_count check was added to the kernel, e.g. see
https://lkml.org/lkml/2002/12/31/83.  Also, the current 'f_count < 2'
check makes PPPIOCDETACH only work in single-threaded applications; it
always fails if called from a multithreaded application.

All pppd versions released in the last 15 years just close() the file
descriptor instead.

Therefore, instead of hacking around this bug by exporting epoll
internals to modules, and probably missing other related bugs, just
remove the PPPIOCDETACH ioctl and see if anyone actually notices.  Leave
a stub in place that prints a one-time warning and returns EINVAL.

Reported-by: syzbot+16363c99d4134717c05b@syzkaller.appspotmail.com
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Guillaume Nault <g.nault@alphalink.fr>
Tested-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-27 21:52:16 +02:00
Martijn Coenen f99ddf91e8 android: binder: add padding to binder_fd_array_object.
binder_fd_array_object starts with a 4-byte header,
followed by a few fields that are 8 bytes when
ANDROID_BINDER_IPC_32BIT=N.

This can cause alignment issues in a 64-bit kernel
with a 32-bit userspace, as on x86_32 an 8-byte primitive
may be aligned to a 4-byte address. Pad with a __u32
to fix this.

Change-Id: I4374ed2cc3ccd3c6a1474cb7209b53ebfd91077b
Signed-off-by: Martijn Coenen <maco@android.com>
2019-07-27 21:52:07 +02:00
Daniel Rosenberg 22bf3fe3ca sdcardfs: Change magic value
Sdcardfs uses the same magic value as wrapfs.
This should not be the case. As it is entirely
in memory, the value can be changed without any
loss of compatibility.

Change-Id: I24200b805d5e6d32702638be99e47d50d7f2f746
Signed-off-by: Daniel Rosenberg <drosen@google.com>
Git-commit: 63fa42ceb9283eaa33d15455e6fe2fe4af61dddd
Git-repo: https://android.googlesource.com/kernel/common.git
Signed-off-by: Srinivasarao P <spathi@codeaurora.org>
2019-07-27 21:51:48 +02:00
Lorenzo Colitti 3fc50a1ee8 BACKPORT: net: xfrm: support setting an output mark.
On systems that use mark-based routing it may be necessary for
routing lookups to use marks in order for packets to be routed
correctly. An example of such a system is Android, which uses
socket marks to route packets via different networks.

Currently, routing lookups in tunnel mode always use a mark of
zero, making routing incorrect on such systems.

This patch adds a new output_mark element to the xfrm state and
a corresponding XFRMA_OUTPUT_MARK netlink attribute. The output
mark differs from the existing xfrm mark in two ways:

1. The xfrm mark is used to match xfrm policies and states, while
   the xfrm output mark is used to set the mark (and influence
   the routing) of the packets emitted by those states.
2. The existing mark is constrained to be a subset of the bits of
   the originating socket or transformed packet, but the output
   mark is arbitrary and depends only on the state.

The use of a separate mark provides additional flexibility. For
example:

- A packet subject to two transforms (e.g., transport mode inside
  tunnel mode) can have two different output marks applied to it,
  one for the transport mode SA and one for the tunnel mode SA.
- On a system where socket marks determine routing, the packets
  emitted by an IPsec tunnel can be routed based on a mark that
  is determined by the tunnel, not by the marks of the
  unencrypted packets.
- Support for setting the output marks can be introduced without
  breaking any existing setups that employ both mark-based
  routing and xfrm tunnel mode. Simply changing the code to use
  the xfrm mark for routing output packets could xfrm mark could
  change behaviour in a way that breaks these setups.

If the output mark is unspecified or set to zero, the mark is not
set or changed.

[backport of upstream 077fbac405bfc6d41419ad6c1725804ad4e9887c]

Bug: 63589535
Test: https://android-review.googlesource.com/452776/ passes
Tested: make allyesconfig; make -j64
Tested: https://android-review.googlesource.com/452776
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: I76120fba036e21780ced31ad390faf491ea81e52
2019-07-27 21:51:33 +02:00
Maciej Żenczykowski 454fd4e57c BACKPORT: ipv6 addrconf: implement RFC7559 router solicitation backoff
This implements:
  https://tools.ietf.org/html/rfc7559

Backoff is performed according to RFC3315 section 14:
  https://tools.ietf.org/html/rfc3315#section-14

We allow setting /proc/sys/net/ipv6/conf/*/router_solicitations
to a negative value meaning an unlimited number of retransmits,
and we make this the new default (inline with the RFC).

We also add a new setting:
  /proc/sys/net/ipv6/conf/*/router_solicitation_max_interval
defaulting to 1 hour (per RFC recommendation).

Signed-off-by: Maciej Żenczykowski <maze@google.com>
Acked-by: Erik Kline <ek@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit bd11f0741fa5a2c296629898ad07759dd12b35bb in
DaveM's net-next/master, should make Linus' tree in 4.9-rc1)
Change-Id: Ia32cdc5c61481893ef8040734e014bf2229fc39e

Git-commit: ce2d59ac01f3b8d29441d29449653fb25bb83f2a
Git-repo: https://android.googlesource.com/kernel/common.git
[resolved trivial merge conflicts]
Signed-off-by: Srinivasarao P <spathi@codeaurora.org>
2019-07-27 21:51:04 +02:00
Joel Scherpelz 18c0b520fe net: ipv6: Add sysctl for minimum prefix len acceptable in RIOs.
This commit adds a new sysctl accept_ra_rt_info_min_plen that
defines the minimum acceptable prefix length of Route Information
Options. The new sysctl is intended to be used together with
accept_ra_rt_info_max_plen to configure a range of acceptable
prefix lengths. It is useful to prevent misconfigurations from
unintentionally blackholing too much of the IPv6 address space
(e.g., home routers announcing RIOs for fc00::/7, which is
incorrect).

[backport of net-next bbea124bc99df968011e76eba105fe964a4eceab]
Bug: 33333670
Test: net_test passes

Change-Id: I5be36ef0e71b4fa9083d7aad2cbb00dd281d778f
Signed-off-by: Joel Scherpelz <jscherpelz@google.com>
Acked-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Git-commit: 161e88ebebc748d1fa51055fc31be6c98db3316e
Git-repo: https://android.googlesource.com/kernel/common.git
Signed-off-by: Srinivasarao P <spathi@codeaurora.org>
2019-07-27 21:51:03 +02:00
Lorenzo Colitti d4e12061f4 net: core: add UID to flows, rules, and routes
- Define a new FIB rule attributes, FRA_UID_RANGE, to describe a
  range of UIDs.
- Define a RTA_UID attribute for per-UID route lookups and dumps.
- Support passing these attributes to and from userspace via
  rtnetlink. The value INVALID_UID indicates no UID was
  specified.
- Add a UID field to the flow structures.

[Backport of net-next 622ec2c9d52405973c9f1ca5116eb1c393adfc7d]

Bug: 16355602
Change-Id: Iea98e6fedd0fd4435a1f4efa3deb3629505619ab
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Git-commit: 0baa8bcd2d48a89ee304051167ded77a10baabcc
Git-repo: https://android.googlesource.com/kernel/common.git
[resolved trivial merge conflicts]
Signed-off-by: Srinivasarao P <spathi@codeaurora.org>
2019-07-27 21:50:59 +02:00
Lorenzo Colitti c03bb93953 Revert "net: core: Support UID-based routing."
This reverts commit 99a6ea48b591877d1cd6a51732c40a1d5321d961.

Bug: 16355602
Change-Id: I7d75b52d8863e932707daf391892480542c2e965

Git-commit: a11e5dc0a6000c5691d2e267893831abc68bd5d9
Git-repo: https://android.googlesource.com/kernel/common.git
[resolved trivial merge conflicts and compilation errors]
Signed-off-by: Srinivasarao P <spathi@codeaurora.org>
2019-07-27 21:50:58 +02:00
Lorenzo Colitti 85c311cf8d net: inet: diag: expose the socket mark to privileged processes.
This adds the capability for a process that has CAP_NET_ADMIN on
a socket to see the socket mark in socket dumps.

Commit a52e95abf772 ("net: diag: allow socket bytecode filters to
match socket marks") recently gave privileged processes the
ability to filter socket dumps based on mark. This patch is
complementary: it ensures that the mark is also passed to
userspace in the socket's netlink attributes.  It is useful for
tools like ss which display information about sockets.

[backport of net-next d545caca827b65aab557a9e9dcdcf1e5a3823c2d]

Change-Id: I0c9708aae5ab8dfa296b8a1e6aecceb2a382415a
Tested: https://android-review.googlesource.com/270210
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Git-commit: 37249459aab0efae6ee7e11d12fc8f790dd32ebc
Git-repo: https://android.googlesource.com/kernel/common.git
Signed-off-by: Srinivasarao P <spathi@codeaurora.org>
2019-07-27 21:50:56 +02:00
Lorenzo Colitti dd33e99cf0 net: diag: allow socket bytecode filters to match socket marks
This allows a privileged process to filter by socket mark when
dumping sockets via INET_DIAG_BY_FAMILY. This is useful on
systems that use mark-based routing such as Android.

The ability to filter socket marks requires CAP_NET_ADMIN, which
is consistent with other privileged operations allowed by the
SOCK_DIAG interface such as the ability to destroy sockets and
the ability to inspect BPF filters attached to packet sockets.

[backport of net-next a52e95abf772b43c9226e9a72d3c1353903ba96f]

Change-Id: Ic02caf628a71007cc7c48c9da220b4088f5aa4f4
Tested: https://android-review.googlesource.com/261350
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Git-commit: d4c5e3877cbaaa2e51e53a853535caf5c8c9ebdc
Git-repo: https://android.googlesource.com/kernel/common.git
Signed-off-by: Srinivasarao P <spathi@codeaurora.org>
2019-07-27 21:50:55 +02:00
David Ahern 7b4866d5b9 net: diag: Add support to filter on device index
Add support to inet_diag facility to filter sockets based on device
index. If an interface index is in the filter only sockets bound
to that index (sk_bound_dev_if) are returned.

[backport of net-next 637c841dd7a5f9bd97b75cbe90b526fa1a52e530]

Change-Id: Ib430cfb44f1b3b1a771a561247ee9140737e52fd
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Git-commit: 41e1e3f25086fdac04df527e9d99b1f4b0d74249
Git-repo: https://android.googlesource.com/kernel/common.git
Signed-off-by: Srinivasarao P <spathi@codeaurora.org>
2019-07-27 21:50:54 +02:00
Mohammed Javid cb68db0577 msm: ipa: New IOCTL for adding rt\flt rule after a specific rule
Added IOCTL for adding a rule on a specific location on the
rt\flt table. The rule will be added after the rule with the
given handle.

Change-Id: I148561fecc7a2e2c9861dbce8975b02947839968
Acked-by: Pooja Kumari <kumarip@qti.qualcomm.com>
Signed-off-by: Mohammed Javid <mjavid@codeaurora.org>
Signed-off-by: Amir Levy <alevy@codeaurora.org>
Signed-off-by: Nadine Toledano <nadinet@codeaurora.org>
2019-07-27 21:50:53 +02:00
Skylar Chang 987c28ae62 msm: ipa: add ioctl to get ipa hw version
Add ioctl for user space to get ipa hw version

Change-Id: Iba207623126f641324fbcf174bddd46552f489de
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>
2019-07-27 21:50:52 +02:00
Amir Levy 50dca023e9 msm: ipa: fix compatibility with ipa_nat driver
Add several defines and structs to allow IPA nat driver compile.
Change IPA_HW_MAX to be a define instead of enum so user space
can check its existence with ifdef.

Change-Id: I33df449d18b678dca44475f04eb72318179dda11
Acked-by: Pooja Kumari <kumarip@qti.qualcomm.com>
Signed-off-by: Mohammed Javid <mjavid@codeaurora.org>
Signed-off-by: Amir Levy <alevy@codeaurora.org>
2019-07-27 21:50:51 +02:00
Skylar Chang e37099ac8a msm: ipa: support aggregated ipa stats query
add support on wan-driver to query modem or
wlan-fw to get the total data usage for all
tethered clients.

Change-Id: I56f40f1c0f6b2ec4279e78b3aeb81c687d08bf2e
Acked-by: Pooja Kumari <kumarip@qti.qualcomm.com>
Signed-off-by: Mohammed Javid <mjavid@codeaurora.org>
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>
2019-07-27 21:50:51 +02:00
Jukka Rissanen 06adc5d1bf BACKPORT: nl80211: Stop scheduled scan if netlink client disappears
(cherry pick from commit 93a1e86ce10e4898f9ca9cd09d659a8a7780ee5e)

An attribute NL80211_ATTR_SOCKET_OWNER can be set by the scan initiator.
If present, the attribute will cause the scan to be stopped if the client
dies.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Bug: 25561044
Change-Id: Ibe4a555b29b64b6df1b9ed4cdcd0f05a69416d14
Git-commit: 5dc2042459d5345c64c35269058a60720f3c6d29
Git-repo: https://android.googlesource.com/kernel/common.git
Signed-off-by: Srinivasarao P <spathi@codeaurora.org>
2019-07-27 21:50:44 +02:00
Johannes Berg fb18d28480 BACKPORT: cfg80211: allow userspace to take ownership of interfaces
(cherry pick from commit 78f22b6a3a9254460d23060530b48ae02a9394e3)

When dynamically creating interfaces from userspace, e.g. for P2P usage,
such interfaces are usually owned by the process that created them, i.e.
wpa_supplicant. Should wpa_supplicant crash, such interfaces will often
cease operating properly and cause problems on restarting the process.

To avoid this problem, introduce an ownership concept for interfaces. If
an interface is owned by a netlink socket, then it will be destroyed if
the netlink socket is closed for any reason, including if the process it
belongs to crashed. This gives us a race-free way to get rid of any such
interfaces.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Bug: 25561044
Change-Id: I5a9c8883c5c204ac5d2917ab8492b44daf4b71e7
Git-commit: 5586920dfea6a8dc963a55572de0256a4faa636e
Git-repo: https://android.googlesource.com/kernel/common.git
[resolved trivial merge conflicts]
Signed-off-by: Srinivasarao P <spathi@codeaurora.org>
2019-07-27 21:50:44 +02:00
Eric Biggers cefb7d7f6f cfg80211: further limit wiphy names to 64 bytes
commit 814596495dd2b9d4aab92d8f89cf19060d25d2ea upstream.

wiphy names were recently limited to 128 bytes by commit a7cfebcb7594
("cfg80211: limit wiphy names to 128 bytes").  As it turns out though,
this isn't sufficient because dev_vprintk_emit() needs the syslog header
string "SUBSYSTEM=ieee80211\0DEVICE=+ieee80211:$devname" to fit into 128
bytes.  This triggered the "device/subsystem name too long" WARN when
the device name was >= 90 bytes.  As before, this was reproduced by
syzbot by sending an HWSIM_CMD_NEW_RADIO command to the MAC80211_HWSIM
generic netlink family.

Fix it by further limiting wiphy names to 64 bytes.

Reported-by: syzbot+e64565577af34b3768dc@syzkaller.appspotmail.com
Fixes: a7cfebcb7594 ("cfg80211: limit wiphy names to 128 bytes")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-27 21:49:36 +02:00
Johannes Berg b462060100 cfg80211: limit wiphy names to 128 bytes
commit a7cfebcb7594a24609268f91299ab85ba064bf82 upstream.

There's currently no limit on wiphy names, other than netlink
message size and memory limitations, but that causes issues when,
for example, the wiphy name is used in a uevent, e.g. in rfkill
where we use the same name for the rfkill instance, and then the
buffer there is "only" 2k for the environment variables.

This was reported by syzkaller, which used a 4k name.

Limit the name to something reasonable, I randomly picked 128.

Reported-by: syzbot+230d9e642a85d3fec29c@syzkaller.appspotmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-27 21:49:11 +02:00
Masakazu Mokuno ded0acf2fb USB: core: Add type-specific length check of BOS descriptors
commit 81cf4a45360f70528f1f64ba018d61cb5767249a upstream.

As most of BOS descriptors are longer in length than their header
'struct usb_dev_cap_header', comparing solely with it is not sufficient
to avoid out-of-bounds access to BOS descriptors.

This patch adds descriptor type specific length check in
usb_get_bos_descriptor() to fix the issue.

Signed-off-by: Masakazu Mokuno <masakazu.mokuno@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.16: drop handling of USB_PTM_CAP_TYPE and USB_SSP_CAP_TYPE]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-27 21:46:13 +02:00
Dmitry V. Levin 6a1485c538 uapi: fix linux/packet_diag.h userspace compilation error
commit 745cb7f8a5de0805cade3de3991b7a95317c7c73 upstream.

Replace MAX_ADDR_LEN with its numeric value to fix the following
linux/packet_diag.h userspace compilation error:

/usr/include/linux/packet_diag.h:67:17: error: 'MAX_ADDR_LEN' undeclared here (not in a function)
  __u8 pdmc_addr[MAX_ADDR_LEN];

This is not the first case in the UAPI where the numeric value
of MAX_ADDR_LEN is used instead of symbolic one, uapi/linux/if_link.h
already does the same:

$ grep MAX_ADDR_LEN include/uapi/linux/if_link.h
	__u8 mac[32]; /* MAX_ADDR_LEN */

There are no UAPI headers besides these two that use MAX_ADDR_LEN.

Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Acked-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2019-07-27 21:44:00 +02:00
Al Viro d585cdd4db allow O_TMPFILE to work with O_WRONLY
Change-Id: I90171d1b53a4c35bfa76757ecfdfb6f95330d107
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-12-03 11:52:37 +01:00
Al Viro 09b20ad836 Safer ABI for O_TMPFILE
[suggested by Rasmus Villemoes] make O_DIRECTORY | O_RDWR part of O_TMPFILE;
that will fail on old kernels in a lot more cases than what I came up with.
And make sure O_CREAT doesn't get there...

Change-Id: Iaa3c8b487d44515b539150bdb5d0b749b87d3ea2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-12-03 11:52:36 +01:00
Al Viro dd8e7e379c it's still short a few helpers, but infrastructure should be OK now...
Change-Id: I0adb8fe9c5029bad3ac52629003c3b78e9442936
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-12-03 11:52:03 +01:00
Subash Abhinov Kasiviswanathan 4f2dd728e1 net: rmnet_data: Add support to configure custom device name
rmnet_data assigns device name by the order they are created.
This causes problems which multiple processes are trying to
create devices and leads to random device names.

Assign device name as specified by user.

[mikeioannina]: Backport to 3.10

CRs-Fixed: 2018785
Change-Id: Iab8e053c6ccacbeedaa7763e760d0c12e756b5d0
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
2018-09-05 18:14:57 +02:00
Greg Kroah-Hartman 5586545b94 USB: fix out-of-bounds in usb_set_configuration
Andrey Konovalov reported a possible out-of-bounds problem for a USB interface
association descriptor.  He writes:
	It seems there's no proper size check of a USB_DT_INTERFACE_ASSOCIATION
	descriptor. It's only checked that the size is >= 2 in
	usb_parse_configuration(), so find_iad() might do out-of-bounds access
	to intf_assoc->bInterfaceCount.

And he's right, we don't check for crazy descriptors of this type very well, so
resolve this problem.  Yet another issue found by syzkaller...

Change-Id: Ibe721523465bd15fc746bdfbf3e7aec908e688bb
Git-commit: bd7a3fe770ebd8391d1c7d072ff88e9e76d063eb
Git-repo: https://github.com/torvalds/linux/commit
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Srinivasa Rao Kuppala <srkupp@codeaurora.org>
2018-08-20 12:09:21 +02:00
Daniel Rosenberg bd934ed2a9 fuse: Add support for d_canonical_path
Allows FUSE to report to inotify that it is acting
as a layered filesystem. The userspace component
returns a string representing the location of the
underlying file. If the string cannot be resolved
into a path, the top level path is returned instead.

bug: 23904372
Change-Id: Iabdca0bbedfbff59e9c820c58636a68ef9683d9f
Signed-off-by: Daniel Rosenberg <drosen@google.com>
2018-02-06 13:12:18 +01:00
Daniel Campello ebe0f70f8d Initial port of sdcardfs
Change-Id: I5b5772a2bbff9f3a7dda641644630a7b8afacec0
2018-02-06 13:12:17 +01:00
Andy Lutomirski 4898f8f010 UPSTREAM: capabilities: ambient capabilities
Credit where credit is due: this idea comes from Christoph Lameter with
a lot of valuable input from Serge Hallyn.  This patch is heavily based
on Christoph's patch.

===== The status quo =====

On Linux, there are a number of capabilities defined by the kernel.  To
perform various privileged tasks, processes can wield capabilities that
they hold.

Each task has four capability masks: effective (pE), permitted (pP),
inheritable (pI), and a bounding set (X).  When the kernel checks for a
capability, it checks pE.  The other capability masks serve to modify
what capabilities can be in pE.

Any task can remove capabilities from pE, pP, or pI at any time.  If a
task has a capability in pP, it can add that capability to pE and/or pI.
If a task has CAP_SETPCAP, then it can add any capability to pI, and it
can remove capabilities from X.

Tasks are not the only things that can have capabilities; files can also
have capabilities.  A file can have no capabilty information at all [1].
If a file has capability information, then it has a permitted mask (fP)
and an inheritable mask (fI) as well as a single effective bit (fE) [2].
File capabilities modify the capabilities of tasks that execve(2) them.

A task that successfully calls execve has its capabilities modified for
the file ultimately being excecuted (i.e.  the binary itself if that
binary is ELF or for the interpreter if the binary is a script.) [3] In
the capability evolution rules, for each mask Z, pZ represents the old
value and pZ' represents the new value.  The rules are:

  pP' = (X & fP) | (pI & fI)
  pI' = pI
  pE' = (fE ? pP' : 0)
  X is unchanged

For setuid binaries, fP, fI, and fE are modified by a moderately
complicated set of rules that emulate POSIX behavior.  Similarly, if
euid == 0 or ruid == 0, then fP, fI, and fE are modified differently
(primary, fP and fI usually end up being the full set).  For nonroot
users executing binaries with neither setuid nor file caps, fI and fP
are empty and fE is false.

As an extra complication, if you execute a process as nonroot and fE is
set, then the "secure exec" rules are in effect: AT_SECURE gets set,
LD_PRELOAD doesn't work, etc.

This is rather messy.  We've learned that making any changes is
dangerous, though: if a new kernel version allows an unprivileged
program to change its security state in a way that persists cross
execution of a setuid program or a program with file caps, this
persistent state is surprisingly likely to allow setuid or file-capped
programs to be exploited for privilege escalation.

===== The problem =====

Capability inheritance is basically useless.

If you aren't root and you execute an ordinary binary, fI is zero, so
your capabilities have no effect whatsoever on pP'.  This means that you
can't usefully execute a helper process or a shell command with elevated
capabilities if you aren't root.

On current kernels, you can sort of work around this by setting fI to
the full set for most or all non-setuid executable files.  This causes
pP' = pI for nonroot, and inheritance works.  No one does this because
it's a PITA and it isn't even supported on most filesystems.

If you try this, you'll discover that every nonroot program ends up with
secure exec rules, breaking many things.

This is a problem that has bitten many people who have tried to use
capabilities for anything useful.

===== The proposed change =====

This patch adds a fifth capability mask called the ambient mask (pA).
pA does what most people expect pI to do.

pA obeys the invariant that no bit can ever be set in pA if it is not
set in both pP and pI.  Dropping a bit from pP or pI drops that bit from
pA.  This ensures that existing programs that try to drop capabilities
still do so, with a complication.  Because capability inheritance is so
broken, setting KEEPCAPS, using setresuid to switch to nonroot uids, and
then calling execve effectively drops capabilities.  Therefore,
setresuid from root to nonroot conditionally clears pA unless
SECBIT_NO_SETUID_FIXUP is set.  Processes that don't like this can
re-add bits to pA afterwards.

The capability evolution rules are changed:

  pA' = (file caps or setuid or setgid ? 0 : pA)
  pP' = (X & fP) | (pI & fI) | pA'
  pI' = pI
  pE' = (fE ? pP' : pA')
  X is unchanged

If you are nonroot but you have a capability, you can add it to pA.  If
you do so, your children get that capability in pA, pP, and pE.  For
example, you can set pA = CAP_NET_BIND_SERVICE, and your children can
automatically bind low-numbered ports.  Hallelujah!

Unprivileged users can create user namespaces, map themselves to a
nonzero uid, and create both privileged (relative to their namespace)
and unprivileged process trees.  This is currently more or less
impossible.  Hallelujah!

You cannot use pA to try to subvert a setuid, setgid, or file-capped
program: if you execute any such program, pA gets cleared and the
resulting evolution rules are unchanged by this patch.

Users with nonzero pA are unlikely to unintentionally leak that
capability.  If they run programs that try to drop privileges, dropping
privileges will still work.

It's worth noting that the degree of paranoia in this patch could
possibly be reduced without causing serious problems.  Specifically, if
we allowed pA to persist across executing non-pA-aware setuid binaries
and across setresuid, then, naively, the only capabilities that could
leak as a result would be the capabilities in pA, and any attacker
*already* has those capabilities.  This would make me nervous, though --
setuid binaries that tried to privilege-separate might fail to do so,
and putting CAP_DAC_READ_SEARCH or CAP_DAC_OVERRIDE into pA could have
unexpected side effects.  (Whether these unexpected side effects would
be exploitable is an open question.) I've therefore taken the more
paranoid route.  We can revisit this later.

An alternative would be to require PR_SET_NO_NEW_PRIVS before setting
ambient capabilities.  I think that this would be annoying and would
make granting otherwise unprivileged users minor ambient capabilities
(CAP_NET_BIND_SERVICE or CAP_NET_RAW for example) much less useful than
it is with this patch.

===== Footnotes =====

[1] Files that are missing the "security.capability" xattr or that have
unrecognized values for that xattr end up with has_cap set to false.
The code that does that appears to be complicated for no good reason.

[2] The libcap capability mask parsers and formatters are dangerously
misleading and the documentation is flat-out wrong.  fE is *not* a mask;
it's a single bit.  This has probably confused every single person who
has tried to use file capabilities.

[3] Linux very confusingly processes both the script and the interpreter
if applicable, for reasons that elude me.  The results from thinking
about a script's file capabilities and/or setuid bits are mostly
discarded.

Preliminary userspace code is here, but it needs updating:
https://git.kernel.org/cgit/linux/kernel/git/luto/util-linux-playground.git/commit/?h=cap_ambient&id=7f5afbd175d2

Here is a test program that can be used to verify the functionality
(from Christoph):

/*
 * Test program for the ambient capabilities. This program spawns a shell
 * that allows running processes with a defined set of capabilities.
 *
 * (C) 2015 Christoph Lameter <cl@linux.com>
 * Released under: GPL v3 or later.
 *
 *
 * Compile using:
 *
 *	gcc -o ambient_test ambient_test.o -lcap-ng
 *
 * This program must have the following capabilities to run properly:
 * Permissions for CAP_NET_RAW, CAP_NET_ADMIN, CAP_SYS_NICE
 *
 * A command to equip the binary with the right caps is:
 *
 *	setcap cap_net_raw,cap_net_admin,cap_sys_nice+p ambient_test
 *
 *
 * To get a shell with additional caps that can be inherited by other processes:
 *
 *	./ambient_test /bin/bash
 *
 *
 * Verifying that it works:
 *
 * From the bash spawed by ambient_test run
 *
 *	cat /proc/$$/status
 *
 * and have a look at the capabilities.
 */

/*
 * Definitions from the kernel header files. These are going to be removed
 * when the /usr/include files have these defined.
 */

static void set_ambient_cap(int cap)
{
	int rc;

	capng_get_caps_process();
	rc = capng_update(CAPNG_ADD, CAPNG_INHERITABLE, cap);
	if (rc) {
		printf("Cannot add inheritable cap\n");
		exit(2);
	}
	capng_apply(CAPNG_SELECT_CAPS);

	/* Note the two 0s at the end. Kernel checks for these */
	if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_RAISE, cap, 0, 0)) {
		perror("Cannot set cap");
		exit(1);
	}
}

int main(int argc, char **argv)
{
	int rc;

	set_ambient_cap(CAP_NET_RAW);
	set_ambient_cap(CAP_NET_ADMIN);
	set_ambient_cap(CAP_SYS_NICE);

	printf("Ambient_test forking shell\n");
	if (execv(argv[1], argv + 1))
		perror("Cannot exec");

	return 0;
}

Signed-off-by: Christoph Lameter <cl@linux.com> # Original author
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Aaron Jones <aaronmdjones@gmail.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Andrew G. Morgan <morgan@kernel.org>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Austin S Hemmelgarn <ahferroin7@gmail.com>
Cc: Markku Savela <msa@moth.iki.fi>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: James Morris <james.l.morris@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 58319057b7847667f0c9585b9de0e8932b0fdb08)

Bug: 31038224
Change-Id: I88bc5caa782dc6be23dc7e839ff8e11b9a903f8c
Signed-off-by: Jorge Lucangeli Obes <jorgelo@google.com>
2018-02-06 13:12:16 +01:00
Martijn Coenen 86d127873a android: binder: support for file-descriptor arrays.
This patch introduces a new binder_fd_array object,
that allows us to support one or more file descriptors
embedded in a buffer that is scatter-gathered.

Change-Id: I647a53cf0d905c7be0dfd9333806982def68dd74
Signed-off-by: Martijn Coenen <maco@google.com>
2018-02-06 13:12:16 +01:00
Martijn Coenen 7965cab5ad android: binder: support for scatter-gather.
Previously all data passed over binder needed
to be serialized, with the exception of Binder
objects and file descriptors.

This patchs adds support for scatter-gathering raw
memory buffers into a binder transaction, avoiding
the need to first serialize them into a Parcel.

To remain backwards compatibile with existing
binder clients, it introduces two new command
ioctls for this purpose - BC_TRANSACTION_SG and
BC_REPLY_SG. These commands may only be used with
the new binder_transaction_data_sg structure,
which adds a field for the total size of the
buffers we are scatter-gathering.

Because memory buffers may contain pointers to
other buffers, we allow callers to specify
a parent buffer and an offset into it, to indicate
this is a location pointing to the buffer that
we are fixing up. The kernel will then take care
of fixing up the pointer to that buffer as well.

Change-Id: I02417f28cff14688f2e1d6fcb959438fd96566cc
Signed-off-by: Martijn Coenen <maco@google.com>
2018-02-06 13:12:16 +01:00
Martijn Coenen bae17ca79b android: binder: split flat_binder_object.
flat_binder_object is used for both handling
binder objects and file descriptors, even though
the two are mostly independent. Since we'll
have more fixup objects in binder in the future,
instead of extending flat_binder_object again,
split out file descriptors to their own object
while retaining backwards compatibility to
existing user-space clients. All binder objects
just share a header.

Change-Id: If3c55f27a2aa8f21815383e0e807be47895e4786
Signed-off-by: Martijn Coenen <maco@google.com>
2018-02-06 13:12:15 +01:00
Theodore Ts'o f6ee685bb3 BACKPORT: random: introduce getrandom(2) system call
Almost clean cherry pick of c6e9d6f38894798696f23c8084ca7edbf16ee895,
includes change made by merge 0891ad829d2a0501053703df66029e843e3b8365.

The getrandom(2) system call was requested by the LibreSSL Portable
developers.  It is analoguous to the getentropy(2) system call in
OpenBSD.

The rationale of this system call is to provide resiliance against
file descriptor exhaustion attacks, where the attacker consumes all
available file descriptors, forcing the use of the fallback code where
/dev/[u]random is not available.  Since the fallback code is often not
well-tested, it is better to eliminate this potential failure mode
entirely.

The other feature provided by this new system call is the ability to
request randomness from the /dev/urandom entropy pool, but to block
until at least 128 bits of entropy has been accumulated in the
/dev/urandom entropy pool.  Historically, the emphasis in the
/dev/urandom development has been to ensure that urandom pool is
initialized as quickly as possible after system boot, and preferably
before the init scripts start execution.

This is because changing /dev/urandom reads to block represents an
interface change that could potentially break userspace which is not
acceptable.  In practice, on most x86 desktop and server systems, in
general the entropy pool can be initialized before it is needed (and
in modern kernels, we will printk a warning message if not).  However,
on an embedded system, this may not be the case.  And so with this new
interface, we can provide the functionality of blocking until the
urandom pool has been initialized.  Any userspace program which uses
this new functionality must take care to assure that if it is used
during the boot process, that it will not cause the init scripts or
other portions of the system startup to hang indefinitely.

SYNOPSIS
	#include <linux/random.h>

	int getrandom(void *buf, size_t buflen, unsigned int flags);

DESCRIPTION
	The system call getrandom() fills the buffer pointed to by buf
	with up to buflen random bytes which can be used to seed user
	space random number generators (i.e., DRBG's) or for other
	cryptographic uses.  It should not be used for Monte Carlo
	simulations or other programs/algorithms which are doing
	probabilistic sampling.

	If the GRND_RANDOM flags bit is set, then draw from the
	/dev/random pool instead of the /dev/urandom pool.  The
	/dev/random pool is limited based on the entropy that can be
	obtained from environmental noise, so if there is insufficient
	entropy, the requested number of bytes may not be returned.
	If there is no entropy available at all, getrandom(2) will
	either block, or return an error with errno set to EAGAIN if
	the GRND_NONBLOCK bit is set in flags.

	If the GRND_RANDOM bit is not set, then the /dev/urandom pool
	will be used.  Unlike using read(2) to fetch data from
	/dev/urandom, if the urandom pool has not been sufficiently
	initialized, getrandom(2) will block (or return -1 with the
	errno set to EAGAIN if the GRND_NONBLOCK bit is set in flags).

	The getentropy(2) system call in OpenBSD can be emulated using
	the following function:

            int getentropy(void *buf, size_t buflen)
            {
                    int     ret;

                    if (buflen > 256)
                            goto failure;
                    ret = getrandom(buf, buflen, 0);
                    if (ret < 0)
                            return ret;
                    if (ret == buflen)
                            return 0;
            failure:
                    errno = EIO;
                    return -1;
            }

RETURN VALUE
       On success, the number of bytes that was filled in the buf is
       returned.  This may not be all the bytes requested by the
       caller via buflen if insufficient entropy was present in the
       /dev/random pool, or if the system call was interrupted by a
       signal.

       On error, -1 is returned, and errno is set appropriately.

ERRORS
	EINVAL		An invalid flag was passed to getrandom(2)

	EFAULT		buf is outside the accessible address space.

	EAGAIN		The requested entropy was not available, and
			getentropy(2) would have blocked if the
			GRND_NONBLOCK flag was not set.

	EINTR		While blocked waiting for entropy, the call was
			interrupted by a signal handler; see the description
			of how interrupted read(2) calls on "slow" devices
			are handled with and without the SA_RESTART flag
			in the signal(7) man page.

NOTES
	For small requests (buflen <= 256) getrandom(2) will not
	return EINTR when reading from the urandom pool once the
	entropy pool has been initialized, and it will return all of
	the bytes that have been requested.  This is the recommended
	way to use getrandom(2), and is designed for compatibility
	with OpenBSD's getentropy() system call.

	However, if you are using GRND_RANDOM, then getrandom(2) may
	block until the entropy accounting determines that sufficient
	environmental noise has been gathered such that getrandom(2)
	will be operating as a NRBG instead of a DRBG for those people
	who are working in the NIST SP 800-90 regime.  Since it may
	block for a long time, these guarantees do *not* apply.  The
	user may want to interrupt a hanging process using a signal,
	so blocking until all of the requested bytes are returned
	would be unfriendly.

	For this reason, the user of getrandom(2) MUST always check
	the return value, in case it returns some error, or if fewer
	bytes than requested was returned.  In the case of
	!GRND_RANDOM and small request, the latter should never
	happen, but the careful userspace code (and all crypto code
	should be careful) should check for this anyway!

	Finally, unless you are doing long-term key generation (and
	perhaps not even then), you probably shouldn't be using
	GRND_RANDOM.  The cryptographic algorithms used for
	/dev/urandom are quite conservative, and so should be
	sufficient for all purposes.  The disadvantage of GRND_RANDOM
	is that it can block, and the increased complexity required to
	deal with partially fulfilled getrandom(2) requests.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Zach Brown <zab@zabbo.net>

Bug: http://b/29621447
Change-Id: I189ba74070dd6d918b0fdf83ff30bb74ec0f7556
(cherry picked from commit 4af712e8df998475736f3e2727701bd31e3751a9)
2017-09-08 18:50:11 +00:00
LuK1337 18aceede84 Merge tag 'LA.BR.1.3.6-03910-8976.0' of https://source.codeaurora.org/quic/la/kernel/msm-3.10 into HEAD
"LA.BR.1.3.6-03910-8976.0"

Change-Id: I16643fc055aa2965fe5903396a8e5158c42cf1bc
2017-05-26 13:28:48 +02:00
Sudarshan Rajagopalan 2a2f0b7463 ashmem: remove cache maintenance support
The cache maintenance routines in ashmem were causing
several security issues. Since they are not being used
anymore by any drivers, its well to remove them entirely.

CRs-Fixed: 1107034, 2001129, 2007786
Change-Id: I955e33d90b888d58db5cf6bb490905283374425b
Signed-off-by: Sudarshan Rajagopalan <sudaraja@codeaurora.org>
2017-04-23 23:34:27 -07:00
Douglas Gilbert ea572a5e74 BACKPORT: sg: relax 16 byte cdb restriction
- remove the 16 byte CDB (SCSI command) length limit from the sg driver
   by handling longer CDBs the same way as the bsg driver. Remove comment
   from sg.h public interface about the cmd_len field being limited to 16
   bytes.
 - remove some dead code caused by this change
 - cleanup comment block at the top of sg.h, fix urls

Change-Id: Ie8150e5375b3316d5d5206f079c4a50f1c50b755
Signed-off-by: Douglas Gilbert <dgilbert@interlog.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Corinna Vinschen <xda@vinschen.de>
2017-04-22 23:03:02 +02:00
Luca Stefani ff1ebfd98d This is the 3.10.102 stable release
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Merge tag 'v3.10.102' into HEAD

This is the 3.10.102 stable release

Change-Id: Ic7d338fb190966b26aa151361fc37414f701d8b2
2017-04-18 17:22:08 +02:00
Luca Stefani 82b37d9f2f Merge remote-tracking branch 'f2fs/linux-3.10.y' into HEAD
Change-Id: Ic2fe24529f029909ddd96490bd6d885d60f88be2
2017-04-18 17:02:28 +02:00
LuK1337 4e71469c73 Merge tag 'LA.BR.1.3.6-03510-8976.0' into HEAD
Change-Id: Ie506850703bf9550ede802c13ba5f8c2ce723fa3
2017-04-18 12:11:50 +02:00
LuK1337 fc9499e55a Import latest Samsung release
* Package version: T713XXU2BQCO

Change-Id: I293d9e7f2df458c512d59b7a06f8ca6add610c99
2017-04-18 03:43:52 +02:00
Jaegeuk Kim 3b11ec9b69 fscrypt: catch up to v4.11-rc1
Keep validate_user_key() due to kasprintf() panic.

fscrypt:
- skcipher_ -> ablkcipher_
- fs/crypto/bio.c changes

f2fs:
- fscrypt: use ENOKEY when file cannot be created w/o key
- fscrypt: split supp and notsupp declarations into their own headers
- fscrypt: make fscrypt_operations.key_prefix a string

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-03-09 11:48:12 -08:00
Deepak Kushwah 5ffb66e3e5 msm: vidc: Allow clients to suggest I-frame sizes
Clients that want to influence the size I-frames emitted by the encoder
can set V4L2_CID_MPEG_VIDC_VIDEO_VENC_IFRAMESIZE_TYPE.

Change-Id: I4e6853022b558069304cde4cff7bc1445fd66213
Signed-off-by: Deepak Kushwah <dkushwah@codeaurora.org>
Signed-off-by: Sanjay Singh <sisanj@codeaurora.org>
2017-02-02 13:17:34 +05:30