Commit Graph

242 Commits

Author SHA1 Message Date
Kees Cook
245d73698e audit: Report suspicious O_CREAT usage
This renames the very specific audit_log_link_denied() to
audit_log_path_denied() and adds the AUDIT_* type as an argument. This
allows for the creation of the new AUDIT_ANOM_CREAT that can be used to
report the fifo/regular file creation restrictions that were introduced
in commit 30aba6656f ("namei: allow restricted O_CREAT of FIFOs and
regular files").

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-10-03 13:59:29 -04:00
Al Viro
fbb7d9d56d kill LOOKUP_NO_EVAL, don't bother including namei.h from audit.h
The former has no users left; the latter was only to get LOOKUP_...
values to remapper in audit_inode() and that's an ex-parrot now.

All places that use symbols from namei.h include it either directly
or (in a few cases) via a local header, like fs/autofs/autofs_i.h

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-08-30 21:29:32 -04:00
Al Viro
c9b07eab0c audit_inode(): switch to passing AUDIT_INODE_...
don't bother with remapping LOOKUP_... values - all callers pass
constants and we can just as well pass the right ones from the
very beginning.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-07-21 18:24:46 -04:00
Linus Torvalds
61fc5771f5 Merge tag 'audit-pr-20190702' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit
Pull audit updates from Paul Moore:
 "This pull request is a bit early, but with some vacation time coming
  up I wanted to send this out now just in case the remote Internet Gods
  decide not to smile on me once the merge window opens. The patchset
  for v5.3 is pretty minor this time, the highlights include:

   - When the audit daemon is sent a signal, ensure we deliver
     information about the sender even when syscall auditing is not
     enabled/supported.

   - Add the ability to filter audit records based on network address
     family.

   - Tighten the audit field filtering restrictions on string based
     fields.

   - Cleanup the audit field filtering verification code.

   - Remove a few BUG() calls from the audit code"

* tag 'audit-pr-20190702' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
  audit: remove the BUG() calls in the audit rule comparison functions
  audit: enforce op for string fields
  audit: add saddr_fam filter field
  audit: re-structure audit field valid checks
  audit: deliver signal_info regarless of syscall
2019-07-08 18:55:42 -07:00
Thomas Gleixner
1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00
Richard Guy Briggs
b48345aafb audit: deliver signal_info regarless of syscall
When a process signals the audit daemon (shutdown, rotate, resume,
reconfig) but syscall auditing is not enabled, we still want to know the
identity of the process sending the signal to the audit daemon.

Move audit_signal_info() out of syscall auditing to general auditing but
create a new function audit_signal_info_syscall() to take care of the
syscall dependent parts for when syscall auditing is enabled.

Please see the github kernel audit issue
https://github.com/linux-audit/audit-kernel/issues/111

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-05-21 22:18:25 -04:00
Ondrej Mosnacek
7e8eda734d ntp: Audit NTP parameters adjustment
Emit an audit record every time selected NTP parameters are modified
from userspace (via adjtimex(2) or clock_adjtime(2)). These parameters
may be used to indirectly change system clock, and thus their
modifications should be audited.

Such events will now generate records of type AUDIT_TIME_ADJNTPVAL
containing the following fields:
  - op -- which value was adjusted:
    - offset -- corresponding to the time_offset variable
    - freq   -- corresponding to the time_freq variable
    - status -- corresponding to the time_status variable
    - adjust -- corresponding to the time_adjust variable
    - tick   -- corresponding to the tick_usec variable
    - tai    -- corresponding to the timekeeping's TAI offset
  - old -- the old value
  - new -- the new value

Example records:

type=TIME_ADJNTPVAL msg=audit(1530616044.507:7): op=status old=64 new=8256
type=TIME_ADJNTPVAL msg=audit(1530616044.511:11): op=freq old=0 new=49180377088000

The records of this type will be associated with the corresponding
syscall records.

An overview of parameter changes that can be done via do_adjtimex()
(based on information from Miroslav Lichvar) and whether they are
audited:
  __timekeeping_set_tai_offset() -- sets the offset from the
                                    International Atomic Time
                                    (AUDITED)
  NTP variables:
    time_offset -- can adjust the clock by up to 0.5 seconds per call
                   and also speed it up or slow down by up to about
                   0.05% (43 seconds per day) (AUDITED)
    time_freq -- can speed up or slow down by up to about 0.05%
                 (AUDITED)
    time_status -- can insert/delete leap seconds and it also enables/
                   disables synchronization of the hardware real-time
                   clock (AUDITED)
    time_maxerror, time_esterror -- change error estimates used to
                                    inform userspace applications
                                    (NOT AUDITED)
    time_constant -- controls the speed of the clock adjustments that
                     are made when time_offset is set (NOT AUDITED)
    time_adjust -- can temporarily speed up or slow down the clock by up
                   to 0.05% (AUDITED)
    tick_usec -- a more extreme version of time_freq; can speed up or
                 slow down the clock by up to 10% (AUDITED)

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-04-15 18:14:01 -04:00
Ondrej Mosnacek
2d87a0674b timekeeping: Audit clock adjustments
Emit an audit record whenever the system clock is changed (i.e. shifted
by a non-zero offset) by a syscall from userspace. The syscalls than can
(at the time of writing) trigger such record are:
  - settimeofday(2), stime(2), clock_settime(2) -- via
    do_settimeofday64()
  - adjtimex(2), clock_adjtime(2) -- via do_adjtimex()

The new records have type AUDIT_TIME_INJOFFSET and contain the following
fields:
  - sec -- the 'seconds' part of the offset
  - nsec -- the 'nanoseconds' part of the offset

Example record (time was shifted backwards by ~15.875 seconds):

type=TIME_INJOFFSET msg=audit(1530616049.652:13): sec=-16 nsec=124887145

The records of this type will be associated with the corresponding
syscall records.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
[PM: fixed a line width problem in __audit_tk_injoffset()]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-04-15 18:10:17 -04:00
Richard Guy Briggs
cd108b5c51 audit: hide auditsc_get_stamp and audit_serial prototypes
auditsc_get_stamp() and audit_serial() are internal audit functions so
move their prototypes from include/linux/audit.h to kernel/audit.h
so they are not visible to the rest of the kernel.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-02-07 21:44:27 -05:00
Richard Guy Briggs
57d4657716 audit: ignore fcaps on umount
Don't fetch fcaps when umount2 is called to avoid a process hang while
it waits for the missing resource to (possibly never) re-appear.

Note the comment above user_path_mountpoint_at():
 * A umount is a special case for path walking. We're not actually interested
 * in the inode in this situation, and ESTALE errors can be a problem.  We
 * simply want track down the dentry and vfsmount attached at the mountpoint
 * and avoid revalidating the last component.

This can happen on ceph, cifs, 9p, lustre, fuse (gluster) or NFS.

Please see the github issue tracker
https://github.com/linux-audit/audit-kernel/issues/100

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: merge fuzz in audit_log_fcaps()]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-01-30 20:51:47 -05:00
Richard Guy Briggs
4b7d248b3a audit: move loginuid and sessionid from CONFIG_AUDITSYSCALL to CONFIG_AUDIT
loginuid and sessionid (and audit_log_session_info) should be part of
CONFIG_AUDIT scope and not CONFIG_AUDITSYSCALL since it is used in
CONFIG_CHANGE, ANOM_LINK, FEATURE_CHANGE (and INTEGRITY_RULE), none of
which are otherwise dependent on AUDITSYSCALL.

Please see github issue
https://github.com/linux-audit/audit-kernel/issues/104

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: tweaked subject line for better grep'ing]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-01-25 13:03:23 -05:00
Paul Moore
2a1fe215e7 audit: use current whenever possible
There are many places, notably audit_log_task_info() and
audit_log_exit(), that take task_struct pointers but in reality they
are always working on the current task.  This patch eliminates the
task_struct arguments and uses current directly which allows a number
of cleanups as well.

Acked-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-26 18:41:21 -05:00
Richard Guy Briggs
0fe3c7fceb audit: localize audit_log_session_info prototype
The audit_log_session_info() function is only used in kernel/audit*, so
move its prototype to kernel/audit.h

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-19 12:26:27 -05:00
Richard Guy Briggs
f7859590d9 audit: eliminate audit_enabled magic number comparison
Remove comparison of audit_enabled to magic numbers outside of audit.

Related: https://github.com/linux-audit/audit-kernel/issues/86

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-06-19 10:43:55 -04:00
Richard Guy Briggs
c0b0ae8a87 audit: use inline function to set audit context
Recognizing that the audit context is an internal audit value, use an
access function to set the audit context pointer for the task
rather than reaching directly into the task struct to set it.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: merge fuzz in audit.h]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-05-14 17:45:21 -04:00
Richard Guy Briggs
cdfb6b341f audit: use inline function to get audit context
Recognizing that the audit context is an internal audit value, use an
access function to retrieve the audit context pointer for the task
rather than reaching directly into the task struct to get it.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: merge fuzz in auditsc.c and selinuxfs.c, checkpatch.pl fixes]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-05-14 17:24:18 -04:00
Richard Guy Briggs
f0b752168d audit: convert sessionid unset to a macro
Use a macro, "AUDIT_SID_UNSET", to replace each instance of
initialization and comparison to an audit session ID.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-05-14 15:56:35 -04:00
Tyler Hicks
326bee0286 seccomp: Don't special case audited processes when logging
Seccomp logging for "handled" actions such as RET_TRAP, RET_TRACE, or
RET_ERRNO can be very noisy for processes that are being audited. This
patch modifies the seccomp logging behavior to treat processes that are
being inspected via the audit subsystem the same as processes that
aren't under inspection. Handled actions will no longer be logged just
because the process is being inspected. Since v4.14, applications have
the ability to request logging of handled actions by using the
SECCOMP_FILTER_FLAG_LOG flag when loading seccomp filters.

With this patch, the logic for deciding if an action will be logged is:

  if action == RET_ALLOW:
    do not log
  else if action not in actions_logged:
    do not log
  else if action == RET_KILL:
    log
  else if action == RET_LOG:
    log
  else if filter-requests-logging:
    log
  else:
    do not log

Reported-by: Steve Grubb <sgrubb@redhat.com>
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-05-08 02:04:23 -04:00
Tyler Hicks
ea6eca7785 seccomp: Audit attempts to modify the actions_logged sysctl
The decision to log a seccomp action will always be subject to the
value of the kernel.seccomp.actions_logged sysctl, even for processes
that are being inspected via the audit subsystem, in an upcoming patch.
Therefore, we need to emit an audit record on attempts at writing to the
actions_logged sysctl when auditing is enabled.

This patch updates the write handler for the actions_logged sysctl to
emit an audit record on attempts to write to the sysctl. Successful
writes to the sysctl will result in a record that includes a normalized
list of logged actions in the "actions" field and a "res" field equal to
1. Unsuccessful writes to the sysctl will result in a record that
doesn't include the "actions" field and has a "res" field equal to 0.

Not all unsuccessful writes to the sysctl are audited. For example, an
audit record will not be emitted if an unprivileged process attempts to
open the sysctl file for reading since that access control check is not
part of the sysctl's write handler.

Below are some example audit records when writing various strings to the
actions_logged sysctl.

Writing "not-a-real-action", when the kernel.seccomp.actions_logged
sysctl previously was "kill_process kill_thread trap errno trace log",
emits this audit record:

 type=CONFIG_CHANGE msg=audit(1525392371.454:120): op=seccomp-logging
 actions=? old-actions=kill_process,kill_thread,trap,errno,trace,log
 res=0

If you then write "kill_process kill_thread errno trace log", this audit
record is emitted:

 type=CONFIG_CHANGE msg=audit(1525392401.645:126): op=seccomp-logging
 actions=kill_process,kill_thread,errno,trace,log
 old-actions=kill_process,kill_thread,trap,errno,trace,log res=1

If you then write "log log errno trace kill_process kill_thread", which
is unordered and contains the log action twice, it results in the same
actions value as the previous record:

 type=CONFIG_CHANGE msg=audit(1525392436.354:132): op=seccomp-logging
 actions=kill_process,kill_thread,errno,trace,log
 old-actions=kill_process,kill_thread,errno,trace,log res=1

If you then write an empty string to the sysctl, this audit record is
emitted:

 type=CONFIG_CHANGE msg=audit(1525392494.413:138): op=seccomp-logging
 actions=(none) old-actions=kill_process,kill_thread,errno,trace,log
 res=1

No audit records are generated when reading the actions_logged sysctl.

Suggested-by: Steve Grubb <sgrubb@redhat.com>
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-05-08 02:03:28 -04:00
Richard Guy Briggs
94b9d9b7a1 audit: remove path param from link denied function
In commit 45b578fe4c
("audit: link denied should not directly generate PATH record")
the need for the struct path *link parameter was removed.
Remove the now useless struct path argument.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-03-21 11:17:41 -04:00
Linus Torvalds
f9bab2677a Merge tag 'audit-pr-20171113' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit
Pull audit updates from Paul Moore:
 "Another relatively small pull request for audit, nine patches total.

  The only real new bit of functionality is the patch from Richard which
  adds the ability to filter records based on the filesystem type.

  The remainder are bug fixes and cleanups; the bug fix highlights
  include:

   - ensuring that we properly audit init/PID-1 (me)

   - allowing the audit daemon to shutdown the kernel/auditd connection
     cleanly by setting the audit PID to zero (Steve)"

* tag 'audit-pr-20171113' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
  audit: filter PATH records keyed on filesystem magic
  Audit: remove unused audit_log_secctx function
  audit: Allow auditd to set pid to 0 to end auditing
  audit: Add new syscalls to the perm=w filter
  audit: use audit_set_enabled() in audit_enable()
  audit: convert audit_ever_enabled to a boolean
  audit: don't use simple_strtol() anymore
  audit: initialize the audit subsystem as early as possible
  audit: ensure that 'audit=1' actually enables audit for PID 1
2017-11-15 13:28:48 -08:00
Casey Schaufler
f7b53637c0 Audit: remove unused audit_log_secctx function
The function audit_log_secctx() is unused in the upstream kernel.
All it does is wrap another function that doesn't need wrapping.
It claims to give you the SELinux context, but that is not true if
you are using a different security module.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-11-10 16:08:47 -05:00
Steve Grubb
de8cd83e91 audit: Record fanotify access control decisions
The fanotify interface allows user space daemons to make access
control decisions. Under common criteria requirements, we need to
optionally record decisions based on policy. This patch adds a bit mask,
FAN_AUDIT, that a user space daemon can 'or' into the response decision
which will tell the kernel that it made a decision and record it.

It would be used something like this in user space code:

  response.response = FAN_DENY | FAN_AUDIT;
  write(fd, &response, sizeof(struct fanotify_response));

When the syscall ends, the audit system will record the decision as a
AUDIT_FANOTIFY auxiliary record to denote that the reason this event
occurred is the result of an access control decision from fanotify
rather than DAC or MAC policy.

A sample event looks like this:

type=PATH msg=audit(1504310584.332:290): item=0 name="./evil-ls"
inode=1319561 dev=fc:03 mode=0100755 ouid=1000 ogid=1000 rdev=00:00
obj=unconfined_u:object_r:user_home_t:s0 nametype=NORMAL
type=CWD msg=audit(1504310584.332:290): cwd="/home/sgrubb"
type=SYSCALL msg=audit(1504310584.332:290): arch=c000003e syscall=2
success=no exit=-1 a0=32cb3fca90 a1=0 a2=43 a3=8 items=1 ppid=901
pid=959 auid=1000 uid=1000 gid=1000 euid=1000 suid=1000
fsuid=1000 egid=1000 sgid=1000 fsgid=1000 tty=pts1 ses=3 comm="bash"
exe="/usr/bin/bash" subj=unconfined_u:unconfined_r:unconfined_t:
s0-s0:c0.c1023 key=(null)
type=FANOTIFY msg=audit(1504310584.332:290): resp=2

Prior to using the audit flag, the developer needs to call
fanotify_init or'ing in FAN_ENABLE_AUDIT to ensure that the kernel
supports auditing. The calling process must also have the CAP_AUDIT_WRITE
capability.

Signed-off-by: sgrubb <sgrubb@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-10-10 13:18:06 +02:00
Linus Torvalds
c0a3a64e72 Merge tag 'seccomp-v4.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull seccomp updates from Kees Cook:
 "Major additions:

   - sysctl and seccomp operation to discover available actions
     (tyhicks)

   - new per-filter configurable logging infrastructure and sysctl
     (tyhicks)

   - SECCOMP_RET_LOG to log allowed syscalls (tyhicks)

   - SECCOMP_RET_KILL_PROCESS as the new strictest possible action

   - self-tests for new behaviors"

[ This is the seccomp part of the security pull request during the merge
  window that was nixed due to unrelated problems   - Linus ]

* tag 'seccomp-v4.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  samples: Unrename SECCOMP_RET_KILL
  selftests/seccomp: Test thread vs process killing
  seccomp: Implement SECCOMP_RET_KILL_PROCESS action
  seccomp: Introduce SECCOMP_RET_KILL_PROCESS
  seccomp: Rename SECCOMP_RET_KILL to SECCOMP_RET_KILL_THREAD
  seccomp: Action to log before allowing
  seccomp: Filter flag to log all actions except SECCOMP_RET_ALLOW
  seccomp: Selftest for detection of filter flag support
  seccomp: Sysctl to configure actions that are allowed to be logged
  seccomp: Operation for checking if an action is available
  seccomp: Sysctl to display available actions
  seccomp: Provide matching filter for introspection
  selftests/seccomp: Refactor RET_ERRNO tests
  selftests/seccomp: Add simple seccomp overhead benchmark
  selftests/seccomp: Add tests for basic ptrace actions
2017-09-22 16:16:41 -10:00
Deepa Dinamani
b904772638 ipc: mqueue: Replace timespec with timespec64
struct timespec is not y2038 safe. Replace
all uses of timespec by y2038 safe struct timespec64.

Even though timespec is used here to represent timeouts,
replace these with timespec64 so that it facilitates
in verification by creating a y2038 safe kernel image
that is free of timespec.

The syscall interfaces themselves are not changed as part
of the patch. They will be part of a different series.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Richard Guy Briggs <rgb@redhat.com>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-03 20:21:24 -04:00