These and similar errors were seen on a patched 3.8 kernel when the
audit subsystem was overrun during boot:

  udevd[876]: worker [887] unexpectedly returned with status 0x0100
  udevd[876]: worker [887] failed while handling
'/devices/pci0000:00/0000:00:03.0/0000:40:00.0'
  udevd[876]: worker [880] unexpectedly returned with status 0x0100
  udevd[876]: worker [880] failed while handling
'/devices/LNXSYSTM:00/LNXPWRBN:00/input/input1/event1'

  udevadm settle - timeout of 180 seconds reached, the event queue
contains:
    /sys/devices/LNXSYSTM:00/LNXPWRBN:00/input/input1/event1 (3995)
    /sys/devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/INT3F0D:00 (4034)

  audit: audit_backlog=258 > audit_backlog_limit=256
  audit: audit_lost=1 audit_rate_limit=0 audit_backlog_limit=256

The change below increases the efficiency of the audit code and prevents it
from being overrun:

Use add_wait_queue_exclusive() in wait_for_auditd() to put the
thread on the wait queue.  When kauditd dequeues an skb, all
of the waiting threads are waiting for the same resource, but
only one is going to get it, so there's no need to wake up
more than one waiter.

See: https://lkml.org/lkml/2013/9/2/479Signed-off-by: NDan Duval <dan.duval@oracle.com>
Signed-off-by: NChuck Anderson <chuck.anderson@oracle.com>
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

These and similar errors were seen on a patched 3.8 kernel when the
audit subsystem was overrun during boot:

  udevd[876]: worker [887] unexpectedly returned with status 0x0100
  udevd[876]: worker [887] failed while handling
'/devices/pci0000:00/0000:00:03.0/0000:40:00.0'
  udevd[876]: worker [880] unexpectedly returned with status 0x0100
  udevd[876]: worker [880] failed while handling
'/devices/LNXSYSTM:00/LNXPWRBN:00/input/input1/event1'

  udevadm settle - timeout of 180 seconds reached, the event queue
contains:
    /sys/devices/LNXSYSTM:00/LNXPWRBN:00/input/input1/event1 (3995)
    /sys/devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/INT3F0D:00 (4034)

  audit: audit_backlog=258 > audit_backlog_limit=256
  audit: audit_lost=1 audit_rate_limit=0 audit_backlog_limit=256

The change below increases the efficiency of the audit code and prevents it
from being overrun:

Only issue a wake_up in kauditd if the length of the skb queue is less than the
backlog limit.  Otherwise, threads waiting in wait_for_auditd() will simply
wake up, discover that the queue is still too long for them to proceed, and go
back to sleep.  This results in wasted context switches and machine cycles.
kauditd_thread() is the only function that removes buffers from audit_skb_queue
so we can't race.  If we did, the timeout in wait_for_auditd() would expire and
the waiting thread would continue.

See: https://lkml.org/lkml/2013/9/2/479Signed-off-by: NDan Duval <dan.duval@oracle.com>
Signed-off-by: NChuck Anderson <chuck.anderson@oracle.com>
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

If wait_for_auditd() times out, go immediately to the error function rather
than retesting the loop conditions.
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

When the audit queue overflows and times out (audit_backlog_wait_time), the
audit queue overflow timeout is set to zero.  Once the audit queue overflow
timeout condition recovers, the timeout should be reset to the original value.

See also:
	https://lkml.org/lkml/2013/9/2/473

Cc: stable@vger.kernel.org # v3.8-rc4+
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NDan Duval <dan.duval@oracle.com>
Signed-off-by: NChuck Anderson <chuck.anderson@oracle.com>
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

Convert audit from only listening in init_net to use register_pernet_subsys()
to dynamically manage the netlink socket list.
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

When being refactored from audit_log_start() to audit_log_task_info(), in
commit e23eb920 the tty and ses fields in the log output got transposed.
Restore to original order to avoid breaking search tools.
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

Normally, netlink ports use the PID of the userspace process as the port ID.
If the PID is already in use by a port, the kernel will allocate another port
ID to avoid conflict.  Re-name all references to netlink ports from pid to
portid to reflect this reality and avoid confusion with actual PIDs.  Ports
use the __u32 type, so re-type all portids accordingly.

(This patch is very similar to ebiederman's 5deadd69)
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

...to make it clear what the intent behind each record's operation was.

In many cases you can infer this, based on the context of the syscall
and the result. In other cases it's not so obvious. For instance, in
the case where you have a file being renamed over another, you'll have
two different records with the same filename but different inode info.
By logging this information we can clearly tell which one was created
and which was deleted.

This fixes what was broken in commit bfcec708.
Commit 79f6530c should also be backported to stable v3.7+.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

In send/GET, we don't want the kernel to lie about what value is set.
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

Using the nlmsg_len member of the netlink header to test if the message
is valid is wrong as it includes the size of the netlink header itself.
Thereby allowing to send short netlink messages that pass those checks.

Use nlmsg_len() instead to test for the right message length. The result
of nlmsg_len() is guaranteed to be non-negative as the netlink message
already passed the checks of nlmsg_ok().

Also switch to min_t() to please checkpatch.pl.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Cc: stable@vger.kernel.org  # v2.6.6+ for the 1st hunk, v2.6.23+ for the 2nd
Signed-off-by: NMathias Krause <minipli@googlemail.com>
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

We currently are setting fields to 0 to initialize the structure
declared on the stack.  This is a bad idea as if the structure has holes
or unpacked space these will not be initialized.  Just use memset.  This
is not a performance critical section of code.
Signed-off-by: NEric Paris <eparis@redhat.com>

We leak 4 bytes of kernel stack in response to an AUDIT_GET request as
we miss to initialize the mask member of status_set. Fix that.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Cc: stable@vger.kernel.org  # v2.6.6+
Signed-off-by: NMathias Krause <minipli@googlemail.com>
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

This adds a new 'audit_feature' bit which allows userspace to set it
such that the loginuid is absolutely immutable, even if you have
CAP_AUDIT_CONTROL.
Signed-off-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

This is a new audit feature which only grants processes with
CAP_AUDIT_CONTROL the ability to unset their loginuid.  They cannot
directly set it from a valid uid to another valid uid.  The ability to
unset the loginuid is nice because a priviledged task, like that of
container creation, can unset the loginuid and then priv is not needed
inside the container when a login daemon needs to set the loginuid.
Signed-off-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

The audit_status structure was not designed with extensibility in mind.
Define a new AUDIT_SET_FEATURE message type which takes a new structure
of bits where things can be enabled/disabled/locked one at a time.  This
structure should be able to grow in the future while maintaining forward
and backward compatibility (based loosly on the ideas from capabilities
and prctl)

This does not actually add any features, but is just infrastructure to
allow new on/off types of audit system features.
Signed-off-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

When the audit=1 kernel parameter is absent and auditd is not running,
AUDIT_USER_AVC messages are being silently discarded.

AUDIT_USER_AVC messages should be sent to userspace using printk(), as
mentioned in the commit message of 4a4cd633 ("AUDIT: Optimise the
audit-disabled case for discarding user messages").

When audit_enabled is 0, audit_receive_msg() discards all user messages
except for AUDIT_USER_AVC messages. However, audit_log_common_recv_msg()
refuses to allocate an audit_buffer if audit_enabled is 0. The fix is to
special case AUDIT_USER_AVC messages in both functions.

It looks like commit 50397bd1 ("[AUDIT] clean up audit_receive_msg()")
introduced this bug.

Cc: <stable@kernel.org> # v2.6.25+
Signed-off-by: NTyler Hicks <tyhicks@canonical.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Cc: linux-audit@redhat.com
Acked-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

Remove it.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

A newline was accidentally added during session ID helper refactorization in
commit 4d3fb709.  This needlessly uses up buffer space, messes up syslog
formatting and makes userspace processing less efficient.  Remove it.
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Acked-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

Signed-off-by: NIlya V. Matveychikov <matvejchikov@gmail.com>
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

Messages of type AUDIT_USER_TTY were being formatted to 1024 octets,
truncating messages approaching MAX_AUDIT_MESSAGE_LENGTH (8970 octets).

Set the formatting to 8560 characters, given maximum estimates for prefix and
suffix budgets.

See the problem discussion:
https://www.redhat.com/archives/linux-audit/2009-January/msg00030.html

And the new size rationale:
https://www.redhat.com/archives/linux-audit/2013-September/msg00016.html

Test ~8k messages with:
auditctl -m "$(for i in $(seq -w 001 820);do echo -n "${i}0______";done)"
Reported-by: NLC Bruzenak <lenny@magitekltd.com>
Reported-by: NJustin Stephenson <jstephen@redhat.com>
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

After commit 82919919 ("kernel/audit.c: avoid negative sleep
durations") audit emitters will block forever if userspace daemon cannot
handle backlog.

After the timeout the waiting loop turns into busy loop and runs until
daemon dies or returns back to work.  This is a minimal patch for that
bug.
Signed-off-by: NKonstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Richard Guy Briggs <rgb@redhat.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: Chuck Anderson <chuck.anderson@oracle.com>
Cc: Dan Duval <dan.duval@oracle.com>
Cc: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

audit_log_start() does wait_for_auditd() in a loop until
audit_backlog_wait_time passes or audit_skb_queue has a room.

If signal_pending() is true this becomes a busy-wait loop, schedule() in
TASK_INTERRUPTIBLE won't block.

Thanks to Guy for fully investigating and explaining the problem.

(akpm: that'll cause the system to lock up on a non-preemptible
uniprocessor kernel)

(Guy: "Our customer was in fact running a uniprocessor machine, and they
reported a system hang.")
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Reported-by: NGuy Streeter <streeter@redhat.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The helper function didn't include a leading space, so it was jammed
against the previous text in the audit record.
Signed-off-by: NEric Paris <eparis@redhat.com>

This reverts commit 6ff5e459.

Conflicts:
	kernel/audit.c

This patch was starting a kthread for all the time.  Since the follow on
patches that required it didn't get finished in 3.10 time, we shouldn't
ship this change in 3.10.
Signed-off-by: NEric Paris <eparis@redhat.com>

The userspace audit tools didn't like the existing formatting of the
AUDIT_ANOM_LINK event. It needed to be expanded to emit an AUDIT_PATH
event as well, so this implements the change. The bulk of the patch is
moving code out of auditsc.c into audit.c and audit.h for general use.
It expands audit_log_name to include an optional "struct path" argument
for the simple case of just needing to report a pathname. This also
makes
audit_log_task_info available when syscall auditing is not enabled,
since
it is needed in either case for process details.
Signed-off-by: NKees Cook <keescook@chromium.org>
Reported-by: NSteve Grubb <sgrubb@redhat.com>

This function is called when we receive a netlink message from
userspace.  We don't need to worry about it coming from irq context or
irqs making it re-entrant.
Signed-off-by: NEric Paris <eparis@redhat.com>

Most commands are entered one line at a time and processed as complete lines
in non-canonical mode.  Commands that interactively require a password, enter
canonical mode to do this while shutting off echo.  This pair of features
(icanon and !echo) can be used to avoid logging passwords by audit while still
logging the rest of the command.

Adding a member (log_passwd) to the struct audit_tty_status passed in by
pam_tty_audit allows control of canonical mode without echo per task.
Signed-off-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

Some of the callers of the audit tty function use spin_lock_irqsave/restore.
We were using the forced always enable version, which seems really bad.
Since I don't know every one of these code paths well enough, it makes
sense to just switch everything to the safe version.  Maybe it's a
little overzealous, but it's a lot better than an unlucky deadlock when
we return to a caller with irq enabled and they expect it to be
disabled.
Signed-off-by: NEric Paris <eparis@redhat.com>

We have a number of places we were reimplementing the same code to write
out lsm labels.  Just do it one darn place.
Signed-off-by: NEric Paris <eparis@redhat.com>

Since we are always current, we can push a lot of this stuff to the
bottom and get rid of useless interfaces and arguments.
Signed-off-by: NEric Paris <eparis@redhat.com>

We always use current.  Stop pulling this when the skb comes in and
pushing it around as arguments.  Just get it at the end when you need
it.
Signed-off-by: NEric Paris <eparis@redhat.com>

We used to have an inflexible mechanism to add audit rules to the
kernel.  It hasn't been used in a long time.  Get rid of that stuff.
Signed-off-by: NEric Paris <eparis@redhat.com>

We only need to check if kauditd is valid after we start it, if kauditd
is invalid, we will set kauditd_task to NULL.  So next time, we will
start kauditd again.

It means if kauditd_task is not NULL,it must be valid.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When userspace sends messages to the audit system it includes a type.
We want to be able to filter messages based on that type without have to
do the all or nothing option currently available on the
AUDIT_FILTER_TYPE filter list.  Instead we should be able to use the
AUDIT_FILTER_USER filter list and just use the message type as one part
of the matching decision.
Signed-off-by: NEric Paris <eparis@redhat.com>

Userspace parsing libraries assume that msg= is only for userspace audit
records, not for user tty records.  Make this consistent with the other
tty records.
Reported-by: NSteve Grubb <sgrubb@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

The kauditd_thread() task was started only after the auditd userspace daemon
registers itself with kaudit.  This was fine when only auditd consumed messages
from the kaudit netlink unicast socket.  With the addition of a multicast group
to that socket it is more convenient to have the thread start on init of the
kaudit kernel subsystem.
Signed-off-by: NRichard Guy Briggs <rbriggs@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

The wait queue control code in kauditd_thread() was nested deeper than
necessary.  The function has been flattened for better legibility.
Signed-off-by: NRichard Guy Briggs <rbriggs@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

The hold queue flush code is an autonomous chunk of code that can be
refactored, removed from kauditd_thread() into flush_hold_queue() and
flattenned for better legibility.
Signed-off-by: NRichard Guy Briggs <rbriggs@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

Commit 94191213 replaced the macros
NLMSG_NEXT with calls to nlmsg_next which produces this warning:

kernel/audit.c: In function ‘audit_receive_skb’:
kernel/audit.c:928:3: warning: passing argument 2 of ‘nlmsg_next’ makes pointer from integer without a cast
In file included from include/net/rtnetlink.h:5:0,
                 from include/net/neighbour.h:28,
                 from include/net/dst.h:17,
                 from include/net/sock.h:68,
                 from kernel/audit.c:55:
include/net/netlink.h:359:1: note: expected ‘int *’ but argument is of type ‘int’

Fix this by sending the intended pointer.
Signed-off-by: NAlexandru Copot <alex.mihai.c@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>