Commit graph

343 commits

Author SHA1 Message Date
Linus Torvalds 0110c350c8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more vfs updates from Al Viro:
 "In this pile:

   - autofs-namespace series
   - dedupe stuff
   - more struct path constification"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (40 commits)
  ocfs2: implement the VFS clone_range, copy_range, and dedupe_range features
  ocfs2: charge quota for reflinked blocks
  ocfs2: fix bad pointer cast
  ocfs2: always unlock when completing dio writes
  ocfs2: don't eat io errors during _dio_end_io_write
  ocfs2: budget for extent tree splits when adding refcount flag
  ocfs2: prohibit refcounted swapfiles
  ocfs2: add newlines to some error messages
  ocfs2: convert inode refcount test to a helper
  simple_write_end(): don't zero in short copy into uptodate
  exofs: don't mess with simple_write_{begin,end}
  9p: saner ->write_end() on failing copy into non-uptodate page
  fix gfs2_stuffed_write_end() on short copies
  fix ceph_write_end()
  nfs_write_end(): fix handling of short copies
  vfs: refactor clone/dedupe_file_range common functions
  fs: try to clone files first in vfs_copy_file_range
  vfs: misc struct path constification
  namespace.c: constify struct path passed to a bunch of primitives
  quota: constify struct path in quota_on
  ...
2016-12-17 18:44:00 -08:00
Linus Torvalds dcdaa2f948 Merge branch 'stable-4.10' of git://git.infradead.org/users/pcmoore/audit
Pull audit updates from Paul Moore:
 "After the small number of patches for v4.9, we've got a much bigger
  pile for v4.10.

  The bulk of these patches involve a rework of the audit backlog queue
  to enable us to move the netlink multicasting out of the task/thread
  that generates the audit record and into the kernel thread that emits
  the record (just like we do for the audit unicast to auditd).

  While we were playing with the backlog queue(s) we fixed a number of
  other little problems with the code, and from all the testing so far
  things look to be in much better shape now. Doing this also allowed us
  to re-enable disabling IRQs for some netns operations ("netns: avoid
  disabling irq for netns id").

  The remaining patches fix some small problems that are well documented
  in the commit descriptions, as well as adding session ID filtering
  support"

* 'stable-4.10' of git://git.infradead.org/users/pcmoore/audit:
  audit: use proper refcount locking on audit_sock
  netns: avoid disabling irq for netns id
  audit: don't ever sleep on a command record/message
  audit: handle a clean auditd shutdown with grace
  audit: wake up kauditd_thread after auditd registers
  audit: rework audit_log_start()
  audit: rework the audit queue handling
  audit: rename the queues and kauditd related functions
  audit: queue netlink multicast sends just like we do for unicast sends
  audit: fixup audit_init()
  audit: move kaudit thread start from auditd registration to kaudit init (#2)
  audit: add support for session ID user filter
  audit: fix formatting of AUDIT_CONFIG_CHANGE events
  audit: skip sessionid sentinel value when auto-incrementing
  audit: tame initialization warning len_abuf in audit_log_execve_info
  audit: less stack usage for /proc/*/loginuid
2016-12-14 14:06:40 -08:00
Richard Guy Briggs 533c7b69c7 audit: use proper refcount locking on audit_sock
Resetting audit_sock appears to be racy.

audit_sock was being copied and dereferenced without using a refcount on
the source sock.

Bump the refcount on the underlying sock when we store a refrence in
audit_sock and release it when we reset audit_sock.  audit_sock
modification needs the audit_cmd_mutex.

See: https://lkml.org/lkml/2016/11/26/232

Thanks to Eric Dumazet <edumazet@google.com> and Cong Wang
<xiyou.wangcong@gmail.com> on ideas how to fix it.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>
[PM: fixed the comment block text formatting for auditd_reset()]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-12-14 13:06:04 -05:00
Paul Moore a09cfa4708 audit: don't ever sleep on a command record/message
Sleeping on a command record/message in audit_log_start() could slow
something, e.g. auditd, from doing something important, e.g. clean
shutdown, which could present problems on a heavily loaded system.
This patch allows tasks to bypass any queue restrictions if they are
logging a command record/message.

Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-12-14 13:06:04 -05:00
Paul Moore 6c54e78996 audit: handle a clean auditd shutdown with grace
When auditd stops cleanly it sets 'auditd_pid' to 0 with an
AUDIT_SET message, in this case we should reset our backlog
queues via the auditd_reset() function.  This patch also adds
a 'auditd_pid' check to the top of kauditd_send_unicast_skb()
so we can fail quicker.

Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-12-14 13:06:04 -05:00
Paul Moore e1d1662128 audit: wake up kauditd_thread after auditd registers
This patch was suggested by Richard Briggs back in 2015, see the link
to the mail archive below.  Unfortunately, that patch is no longer
even remotely valid due to other changes to the code.

* https://www.redhat.com/archives/linux-audit/2015-October/msg00075.html

Suggested-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-12-14 13:06:04 -05:00
Paul Moore 3197542482 audit: rework audit_log_start()
The backlog queue handling in audit_log_start() is a little odd with
some questionable design decisions, this patch attempts to rectify
this with the following changes:

* Never make auditd wait, ignore any backlog limits as we need auditd
awake so it can drain the backlog queue.

* When we hit a backlog limit and start dropping records, don't wake
all the tasks sleeping on the backlog, that's silly.  Instead, let
kauditd_thread() take care of waking everyone once it has had a chance
to drain the backlog queue.

* Don't keep a global backlog timeout countdown, make it per-task.  A
per-task timer means we won't have all the sleeping tasks waking at
the same time and hammering on an already stressed backlog queue.

Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-12-14 13:06:04 -05:00
Paul Moore c6480207fd audit: rework the audit queue handling
The audit record backlog queue has always been a bit of a mess, and
the moving the multicast send into kauditd_thread() from
audit_log_end() only makes things worse.  This patch attempts to fix
the backlog queue with a better design that should hold up better
under load and have less of a performance impact at syscall
invocation time.

While it looks like there is a log going on in this patch, the main
change is the move from a single backlog queue to three queues:

* A queue for holding records generated from audit_log_end() that
haven't been consumed by kauditd_thread() (audit_queue).

* A queue for holding records that have been sent via multicast but
had a temporary failure when sending via unicast and need a resend
(audit_retry_queue).

* A queue for holding records that haven't been sent via unicast
because no one is listening (audit_hold_queue).

Special care is taken in this patch to ensure that the proper
record ordering is preserved, e.g. we send everything in the hold
queue first, then the retry queue, and finally the main queue.

Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-12-14 13:06:04 -05:00
Paul Moore af8b824f28 audit: rename the queues and kauditd related functions
The audit queue names can be shortened and the record sending
helpers associated with the kauditd task could be named better, do
these small cleanups now to make life easier once we start reworking
the queues and kauditd code.

Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-12-14 13:06:04 -05:00
Paul Moore 4aa83872d3 audit: queue netlink multicast sends just like we do for unicast sends
Sending audit netlink multicast messages is bad for all the same
reasons that sending audit netlink unicast messages is bad, so this
patch reworks things so that we don't do the multicast send in
audit_log_end(), we do it from the dedicated kauditd_thread thread just
as we do for unicast messages.

See the GitHub issues below for more information/history:

 * https://github.com/linux-audit/audit-kernel/issues/23
 * https://github.com/linux-audit/audit-kernel/issues/22

Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-12-14 13:06:04 -05:00
Paul Moore 6c92556453 audit: fixup audit_init()
Make sure everything is initialized before we start the kauditd_thread
and don't emit the "initialized" record until everything is finished.
We also panic with a descriptive message if we can't start the
kauditd_thread.

Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-12-14 13:06:04 -05:00
Richard Guy Briggs 55a6f170a4 audit: move kaudit thread start from auditd registration to kaudit init (#2)
Richard made this change some time ago but Eric backed it out because
the rest of the supporting code wasn't ready.  In order to move the
netlink multicast send to kauditd_thread we need to ensure the
kauditd_thread is always running, so restore commit 6ff5e459 ("audit:
move kaudit thread start from auditd registration to kaudit init").

Signed-off-by: Richard Guy Briggs <rbriggs@redhat.com>
[PM: brought forward and merged based on Richard's old patch]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-12-14 13:06:04 -05:00
Al Viro 8bd107633b audit_log_{name,link_denied}: constify struct path
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-05 19:00:38 -05:00
WANG Cong 6060298272 audit: remove useless synchronize_net()
netlink kernel socket is protected by refcount, not RCU.
Its rcv path is neither protected by RCU. So the synchronize_net()
is just pointless.

Cc: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-01 11:29:02 -05:00
Alexey Dobriyan c7d03a00b5 netns: make struct pernet_operations::id unsigned int
Make struct pernet_operations::id unsigned.

There are 2 reasons to do so:

1)
This field is really an index into an zero based array and
thus is unsigned entity. Using negative value is out-of-bound
access by definition.

2)
On x86_64 unsigned 32-bit data which are mixed with pointers
via array indexing or offsets added or subtracted to pointers
are preffered to signed 32-bit data.

"int" being used as an array index needs to be sign-extended
to 64-bit before being used.

	void f(long *p, int i)
	{
		g(p[i]);
	}

  roughly translates to

	movsx	rsi, esi
	mov	rdi, [rsi+...]
	call 	g

MOVSX is 3 byte instruction which isn't necessary if the variable is
unsigned because x86_64 is zero extending by default.

Now, there is net_generic() function which, you guessed it right, uses
"int" as an array index:

	static inline void *net_generic(const struct net *net, int id)
	{
		...
		ptr = ng->ptr[id - 1];
		...
	}

And this function is used a lot, so those sign extensions add up.

Patch snipes ~1730 bytes on allyesconfig kernel (without all junk
messing with code generation):

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)

Unfortunately some functions actually grow bigger.
This is a semmingly random artefact of code generation with register
allocator being used differently. gcc decides that some variable
needs to live in new r8+ registers and every access now requires REX
prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be
used which is longer than [r8]

However, overall balance is in negative direction:

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
	function                                     old     new   delta
	nfsd4_lock                                  3886    3959     +73
	tipc_link_build_proto_msg                   1096    1140     +44
	mac80211_hwsim_new_radio                    2776    2808     +32
	tipc_mon_rcv                                1032    1058     +26
	svcauth_gss_legacy_init                     1413    1429     +16
	tipc_bcbase_select_primary                   379     392     +13
	nfsd4_exchange_id                           1247    1260     +13
	nfsd4_setclientid_confirm                    782     793     +11
		...
	put_client_renew_locked                      494     480     -14
	ip_set_sockfn_get                            730     716     -14
	geneve_sock_add                              829     813     -16
	nfsd4_sequence_done                          721     703     -18
	nlmclnt_lookup_host                          708     686     -22
	nfsd4_lockt                                 1085    1063     -22
	nfs_get_client                              1077    1050     -27
	tcf_bpf_init                                1106    1076     -30
	nfsd4_encode_fattr                          5997    5930     -67
	Total: Before=154856051, After=154854321, chg -0.00%

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-18 10:59:15 -05:00
Linus Torvalds 3cd013ab79 Merge branch 'stable-4.9' of git://git.infradead.org/users/pcmoore/audit
Pull audit updates from Paul Moore:
 "Another relatively small pull request for v4.9 with just two patches.

  The patch from Richard updates the list of features we support and
  report back to userspace; this should have been sent earlier with the
  rest of the v4.8 patches but it got lost in my inbox.

  The second patch fixes a problem reported by our Android friends where
  we weren't very consistent in recording PIDs"

* 'stable-4.9' of git://git.infradead.org/users/pcmoore/audit:
  audit: add exclude filter extension to feature bitmap
  audit: consistently record PIDs with task_tgid_nr()
2016-10-04 14:21:41 -07:00
Paul Moore fa2bea2f5c audit: consistently record PIDs with task_tgid_nr()
Unfortunately we record PIDs in audit records using a variety of
methods despite the correct way being the use of task_tgid_nr().
This patch converts all of these callers, except for the case of
AUDIT_SET in audit_receive_msg() (see the comment in the code).

Reported-by: Jeff Vander Stoep <jeffv@google.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-08-30 17:19:13 -04:00
Linus Torvalds 797cee982e Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit
Pull audit updates from Paul Moore:
 "Six audit patches for 4.8.

  There are a couple of style and minor whitespace tweaks for the logs,
  as well as a minor fixup to catch errors on user filter rules, however
  the major improvements are a fix to the s390 syscall argument masking
  code (reviewed by the nice s390 folks), some consolidation around the
  exclude filtering (less code, always a win), and a double-fetch fix
  for recording the execve arguments"

* 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit:
  audit: fix a double fetch in audit_log_single_execve_arg()
  audit: fix whitespace in CWD record
  audit: add fields to exclude filter by reusing user filter
  s390: ensure that syscall arguments are properly masked on s390
  audit: fix some horrible switch statement style crimes
  audit: fixup: log on errors from filter user rules
2016-07-29 17:54:17 -07:00
Linus Torvalds 89a82a9218 Merge branch 'stable-4.7' of git://git.infradead.org/users/pcmoore/audit
Pull audit fixes from Paul Moore:
 "Two small patches to fix audit problems in 4.7-rcX: the first fixes a
  potential kref leak, the second removes some header file noise.

  The first is an important bug fix that really should go in before 4.7
  is released, the second is not critical, but falls into the very-nice-
  to-have category so I'm including in the pull request.

  Both patches are straightforward, self-contained, and pass our
  testsuite without problem"

* 'stable-4.7' of git://git.infradead.org/users/pcmoore/audit:
  audit: move audit_get_tty to reduce scope and kabi changes
  audit: move calcs after alloc and check when logging set loginuid
2016-06-29 15:18:47 -07:00
Richard Guy Briggs 3f5be2da85 audit: move audit_get_tty to reduce scope and kabi changes
The only users of audit_get_tty and audit_put_tty are internal to
audit, so move it out of include/linux/audit.h to kernel.h and create
a proper function rather than inlining it.  This also reduces kABI
changes.

Suggested-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: line wrapped description]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-06-28 15:48:48 -04:00
Richard Guy Briggs 86b2efbe3a audit: add fields to exclude filter by reusing user filter
RFE: add additional fields for use in audit filter exclude rules
https://github.com/linux-audit/audit-kernel/issues/5

Re-factor and combine audit_filter_type() with audit_filter_user() to
use audit_filter_user_rules() to enable the exclude filter to
additionally filter on PID, UID, GID, AUID, LOGINUID_SET, SUBJ_*.

The process of combining the similar audit_filter_user() and
audit_filter_type() functions, required inverting the meaning and
including the ALWAYS action of the latter.

Include audit_filter_user_rules() into audit_filter(), removing
unneeded logic in the process.

Keep the check to quit early if the list is empty.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: checkpatch.pl fixes - whitespace damage, wrapped description]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-06-27 11:01:00 -04:00
Linus Torvalds 03e1aa1cbb Merge branch 'stable-4.7' of git://git.infradead.org/users/pcmoore/audit
Pull audit updates from Paul Moore:
 "Four small audit patches for 4.7.

  Two are simple cleanups around the audit thread management code, one
  adds a tty field to AUDIT_LOGIN events, and the final patch makes
  tty_name() usable regardless of CONFIG_TTY.

  Nothing controversial, and it all passes our regression test"

* 'stable-4.7' of git://git.infradead.org/users/pcmoore/audit:
  tty: provide tty_name() even without CONFIG_TTY
  audit: add tty field to LOGIN event
  audit: we don't need to __set_current_state(TASK_RUNNING)
  audit: cleanup prune_tree_thread
2016-05-18 18:46:55 -07:00
Richard Guy Briggs db0a6fb5d9 audit: add tty field to LOGIN event
The tty field was missing from AUDIT_LOGIN events.

Refactor code to create a new function audit_get_tty(), using it to
replace the call in audit_log_task_info() and to add it to
audit_log_set_loginuid().  Lock and bump the kref to protect it, adding
audit_put_tty() alias to decrement it.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-04-26 17:19:16 -04:00
Paul Moore 7ffb8e317b audit: we don't need to __set_current_state(TASK_RUNNING)
Remove the calls to __set_current_state() to mark the task as running
and do some related cleanup in wait_for_auditd() to limit the amount
of work we do when we aren't going to reschedule the current task.

Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-04-04 16:44:02 -04:00
Linus Torvalds 51b3eae8db Merge branch 'stable-4.6' of git://git.infradead.org/users/pcmoore/audit
Pull audit updates from Paul Moore:
 "A small set of patches for audit this time; just three in total and
  one is a spelling fix.

  The two patches with actual content are designed to help prevent new
  instances of auditd from displacing an existing, functioning auditd
  and to generate a log of the attempt.  Not to worry, dead/stuck auditd
  instances can still be replaced by a new instance without problem.

  Nothing controversial, and everything passes our regression suite"

* 'stable-4.6' of git://git.infradead.org/users/pcmoore/audit:
  audit: Fix typo in comment
  audit: log failed attempts to change audit_pid configuration
  audit: stop an old auditd being starved out by a new auditd
2016-03-19 17:52:49 -07:00
Peter Hurley 2e28d38ae1 tty: audit: Handle tty audit enable atomically
The audit_tty and audit_tty_log_passwd fields are actually bool
values, so merge into single memory location to access atomically.

NB: audit log operations may still occur after tty audit is disabled
which is consistent with the existing functionality

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27 16:41:04 -08:00
Peter Hurley 37282a7795 tty: audit: Combine push functions
tty_audit_push() and tty_audit_push_current() perform identical
tasks; eliminate the tty_audit_push() implementation and the
tty_audit_push_current() name.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27 16:41:04 -08:00
Richard Guy Briggs 935c9e7ff0 audit: log failed attempts to change audit_pid configuration
Failed attempts to change the audit_pid configuration are not presently
logged.  One case is an attempt to starve an old auditd by starting up
a new auditd when the old one is still alive and active.  The other
case is an attempt to orphan a new auditd when an old auditd shuts
down.

Log both as AUDIT_CONFIG_CHANGE messages with failure result.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2016-01-25 18:04:15 -05:00
Richard Guy Briggs 133e1e5acd audit: stop an old auditd being starved out by a new auditd
Nothing prevents a new auditd starting up and replacing a valid
audit_pid when an old auditd is still running, effectively starving out
the old auditd since audit_pid no longer points to the old valid
auditd.

If no message to auditd has been attempted since auditd died
unnaturally or got killed, audit_pid will still indicate it is alive.
There isn't an easy way to detect if an old auditd is still running on
the existing audit_pid other than attempting to send a message to see
if it fails.  An -ECONNREFUSED almost certainly means it disappeared
and can be replaced.  Other errors are not so straightforward and may
indicate transient problems that will resolve themselves and the old
auditd will recover.  Yet others will likely need manual intervention
for which a new auditd will not solve the problem.

Send a new message type (AUDIT_REPLACE) to the old auditd containing a
u32 with the PID of the new auditd.  If the audit replace message
succeeds (or doesn't fail with certainty), fail to register the new
auditd and return an error (-EEXIST).

This is expected to make the patch preventing an old auditd orphaning a
new auditd redundant.

V3: Switch audit message type from 1000 to 1300 block.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2016-01-25 18:04:15 -05:00
Linus Torvalds 5807fcaa9b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:

 - EVM gains support for loading an x509 cert from the kernel
   (EVM_LOAD_X509), into the EVM trusted kernel keyring.

 - Smack implements 'file receive' process-based permission checking for
   sockets, rather than just depending on inode checks.

 - Misc enhancments for TPM & TPM2.

 - Cleanups and bugfixes for SELinux, Keys, and IMA.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (41 commits)
  selinux: Inode label revalidation performance fix
  KEYS: refcount bug fix
  ima: ima_write_policy() limit locking
  IMA: policy can be updated zero times
  selinux: rate-limit netlink message warnings in selinux_nlmsg_perm()
  selinux: export validatetrans decisions
  gfs2: Invalid security labels of inodes when they go invalid
  selinux: Revalidate invalid inode security labels
  security: Add hook to invalidate inode security labels
  selinux: Add accessor functions for inode->i_security
  security: Make inode argument of inode_getsecid non-const
  security: Make inode argument of inode_getsecurity non-const
  selinux: Remove unused variable in selinux_inode_init_security
  keys, trusted: seal with a TPM2 authorization policy
  keys, trusted: select hash algorithm for TPM2 chips
  keys, trusted: fix: *do not* allow duplicate key options
  tpm_ibmvtpm: properly handle interrupted packet receptions
  tpm_tis: Tighten IRQ auto-probing
  tpm_tis: Refactor the interrupt setup
  tpm_tis: Get rid of the duplicate IRQ probing code
  ...
2016-01-17 19:13:15 -08:00
Markus Elfring d865e573b8 audit: Delete unnecessary checks before two function calls
The functions consume_skb() and kfree_skb() test whether their argument
is NULL and then return immediately.
Thus the tests around their calls are not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
[PM: tweak patch prefix]
Signed-off-by: Paul Moore <pmoore@redhat.com>
2016-01-13 09:18:55 -05:00
Richard Guy Briggs 1194b994be audit: wake up threads if queue switched from limited to unlimited
If the audit_backlog_limit is changed from a limited value to an
unlimited value (zero) while the queue was overflowed, wake up the
audit_backlog_wait queue to allow those processes to continue.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2016-01-13 09:18:54 -05:00
Richard Guy Briggs f48a942926 audit: include auditd's threads in audit_log_start() wait exception
Should auditd spawn threads, allow all members of its thread group to
use the audit_backlog_limit reserves to bypass the queue limits too.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: minor upstream merge tweaks]
Signed-off-by: Paul Moore <pmoore@redhat.com>
2016-01-13 09:15:19 -05:00
Paul Moore eb8baf6aa3 audit: remove audit_backlog_wait_overflow
It seems much more obvious and readable to simply use "0".

Signed-off-by: Paul Moore <pmoore@redhat.com>
2016-01-13 09:15:18 -05:00
Richard Guy Briggs c4b7a7755f audit: don't needlessly reset valid wait time
After auditd has recovered from an overflowed queue, the first process
that doesn't use reserves to make it through the queue checks should
reset the audit backlog wait time to the configured value.  After that,
there is no need to keep resetting it.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2016-01-13 09:15:18 -05:00
Andreas Gruenbacher d6335d77a7 security: Make inode argument of inode_getsecid non-const
Make the inode argument of the inode_getsecid hook non-const so that we
can use it to revalidate invalid security labels.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-12-24 11:09:39 -05:00
Mel Gorman d0164adc89 mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd
__GFP_WAIT has been used to identify atomic context in callers that hold
spinlocks or are in interrupts.  They are expected to be high priority and
have access one of two watermarks lower than "min" which can be referred
to as the "atomic reserve".  __GFP_HIGH users get access to the first
lower watermark and can be called the "high priority reserve".

Over time, callers had a requirement to not block when fallback options
were available.  Some have abused __GFP_WAIT leading to a situation where
an optimisitic allocation with a fallback option can access atomic
reserves.

This patch uses __GFP_ATOMIC to identify callers that are truely atomic,
cannot sleep and have no alternative.  High priority users continue to use
__GFP_HIGH.  __GFP_DIRECT_RECLAIM identifies callers that can sleep and
are willing to enter direct reclaim.  __GFP_KSWAPD_RECLAIM to identify
callers that want to wake kswapd for background reclaim.  __GFP_WAIT is
redefined as a caller that is willing to enter direct reclaim and wake
kswapd for background reclaim.

This patch then converts a number of sites

o __GFP_ATOMIC is used by callers that are high priority and have memory
  pools for those requests. GFP_ATOMIC uses this flag.

o Callers that have a limited mempool to guarantee forward progress clear
  __GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall
  into this category where kswapd will still be woken but atomic reserves
  are not used as there is a one-entry mempool to guarantee progress.

o Callers that are checking if they are non-blocking should use the
  helper gfpflags_allow_blocking() where possible. This is because
  checking for __GFP_WAIT as was done historically now can trigger false
  positives. Some exceptions like dm-crypt.c exist where the code intent
  is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to
  flag manipulations.

o Callers that built their own GFP flags instead of starting with GFP_KERNEL
  and friends now also need to specify __GFP_KSWAPD_RECLAIM.

The first key hazard to watch out for is callers that removed __GFP_WAIT
and was depending on access to atomic reserves for inconspicuous reasons.
In some cases it may be appropriate for them to use __GFP_HIGH.

The second key hazard is callers that assembled their own combination of
GFP flags instead of starting with something like GFP_KERNEL.  They may
now wish to specify __GFP_KSWAPD_RECLAIM.  It's almost certainly harmless
if it's missed in most cases as other activity will wake kswapd.

Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06 17:50:42 -08:00
Paul Moore 233a68667c audit: make audit_log_common_recv_msg() a void function
It always returns zero and no one is checking the return value.

Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-11-04 08:23:52 -05:00
Saurabh Sengar c5ea6efda6 audit: removing unused variable
Variable rc in not required as it is just used for unchanged for return,
and return is always 0 in the function.

Signed-off-by: Saurabh Sengar <saurabh.truth@gmail.com>
[PM: fixed spelling errors in description]
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-11-04 08:23:52 -05:00
Yaowei Bai 9fcf836b21 audit: audit_string_contains_control can be boolean
This patch makes audit_string_contains_control return bool to improve
readability due to this particular function only using either one or
zero as its return value.

Signed-off-by: Yaowei Bai <bywxiaobai@163.com>
[PM: tweaked subject line]
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-11-04 08:23:51 -05:00
Richard Guy Briggs 32a1dbaece audit: try harder to send to auditd upon netlink failure
There are several reports of the kernel losing contact with auditd when
it is, in fact, still running.  When this happens, kernel syslogs show:
	"audit: *NO* daemon at audit_pid=<pid>"
although auditd is still running, and is apparently happy, listening on
the netlink socket. The pid in the "*NO* daemon" message matches the pid
of the running auditd process.  Restarting auditd solves this.

The problem appears to happen randomly, and doesn't seem to be strongly
correlated to the rate of audit events being logged.  The problem
happens fairly regularly (every few days), but not yet reproduced to
order.

On production kernels, BUG_ON() is a no-op, so any error will trigger
this.

Commit 34eab0a7cd ("audit: prevent an older auditd shutdown from
orphaning a newer auditd startup") eliminates one possible cause.  This
isn't the case here, since the PID in the error message and the PID of
the running auditd match.

The primary expected cause of error here is -ECONNREFUSED when the audit
daemon goes away, when netlink_getsockbyportid() can't find the auditd
portid entry in the netlink audit table (or there is no receive
function).  If -EPERM is returned, that situation isn't likely to be
resolved in a timely fashion without administrator intervention.  In
both cases, reset the audit_pid.  This does not rule out a race
condition.  SELinux is expected to return zero since this isn't an INET
or INET6 socket.  Other LSMs may have other return codes.  Log the error
code for better diagnosis in the future.

In the case of -ENOMEM, the situation could be temporary, based on local
or general availability of buffers.  -EAGAIN should never happen since
the netlink audit (kernel) socket is set to MAX_SCHEDULE_TIMEOUT.
-ERESTARTSYS and -EINTR are not expected since this kernel thread is not
expected to receive signals.  In these cases (or any other unexpected
ones for now), report the error and re-schedule the thread, retrying up
to 5 times.

v2:
	Removed BUG_ON().
	Moved comma in pr_*() statements.
	Removed audit_strerror() text.

Reported-by: Vipin Rathor <v.rathor@gmail.com>
Reported-by: <ctcard@hotmail.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: applied rgb's fixup patch to correct audit_log_lost() format issues]
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-11-04 08:23:50 -05:00
Linus Torvalds 425afcff13 Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit
Pull audit update from Paul Moore:
 "This is one of the larger audit patchsets in recent history,
  consisting of eight patches and almost 400 lines of changes.

  The bulk of the patchset is the new "audit by executable"
  functionality which allows admins to set an audit watch based on the
  executable on disk.  Prior to this, admins could only track an
  application by PID, which has some obvious limitations.

  Beyond the new functionality we also have some refcnt fixes and a few
  minor cleanups"

* 'upstream' of git://git.infradead.org/users/pcmoore/audit:
  fixup: audit: implement audit by executable
  audit: implement audit by executable
  audit: clean simple fsnotify implementation
  audit: use macros for unset inode and device values
  audit: make audit_del_rule() more robust
  audit: fix uninitialized variable in audit_add_rule()
  audit: eliminate unnecessary extra layer of watch parent references
  audit: eliminate unnecessary extra layer of watch references
2015-09-08 13:34:59 -07:00
Richard Guy Briggs 84cb777e67 audit: use macros for unset inode and device values
Clean up a number of places were casted magic numbers are used to represent
unset inode and device numbers in preparation for the audit by executable path
patch set.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: enclosed the _UNSET macros in parentheses for ./scripts/checkpatch]
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-08-06 14:39:02 -04:00
Linus Torvalds 4a10a91756 Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit
Pull audit updates from Paul Moore:
 "Four small audit patches for v4.2, all bug fixes.  Only 10 lines of
  change this time so very unremarkable, the patch subject lines pretty
  much tell the whole story"

* 'upstream' of git://git.infradead.org/users/pcmoore/audit:
  audit: Fix check of return value of strnlen_user()
  audit: obsolete audit_context check is removed in audit_filter_rules()
  audit: fix for typo in comment to function audit_log_link_denied()
  lsm: rename duplicate labels in LSM_AUDIT_DATA_TASK audit message type
2015-06-27 13:53:16 -07:00
Shailendra Verma 2201196479 audit: fix for typo in comment to function audit_log_link_denied()
Signed-off-by: Shailendra Verma <shailendra.capricorn@gmail.com>
[PM: tweaked subject line]
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-05-29 15:19:02 -04:00
Linus Torvalds 9ec3a646fe Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull fourth vfs update from Al Viro:
 "d_inode() annotations from David Howells (sat in for-next since before
  the beginning of merge window) + four assorted fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  RCU pathwalk breakage when running into a symlink overmounting something
  fix I_DIO_WAKEUP definition
  direct-io: only inc/dec inode->i_dio_count for file systems
  fs/9p: fix readdir()
  VFS: assorted d_backing_inode() annotations
  VFS: fs/inode.c helpers: d_inode() annotations
  VFS: fs/cachefiles: d_backing_inode() annotations
  VFS: fs library helpers: d_inode() annotations
  VFS: assorted weird filesystems: d_inode() annotations
  VFS: normal filesystems (and lustre): d_inode() annotations
  VFS: security/: d_inode() annotations
  VFS: security/: d_backing_inode() annotations
  VFS: net/: d_inode() annotations
  VFS: net/unix: d_backing_inode() annotations
  VFS: kernel/: d_inode() annotations
  VFS: audit: d_backing_inode() annotations
  VFS: Fix up some ->d_inode accesses in the chelsio driver
  VFS: Cachefiles should perform fs modifications on the top layer only
  VFS: AF_UNIX sockets should call mknod on the top layer only
2015-04-26 17:22:07 -07:00
Linus Torvalds 27cf3a16b2 Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit
Pull audit fixes from Paul Moore:
 "Seven audit patches for v4.1, all bug fixes.

  The largest, and perhaps most significant commit helps resolve some
  memory pressure issues related to the inode cache and audit, there are
  also a few small commits which help resolve some timing issues with
  the audit log queue, and the rest fall into the always popular "code
  clean-up" category.

  In general, nothing really substantial, just a nice set of maintenance
  patches"

* 'upstream' of git://git.infradead.org/users/pcmoore/audit:
  audit: Remove condition which always evaluates to false
  audit: reduce mmap_sem hold for mm->exe_file
  audit: consolidate handling of mm->exe_file
  audit: code clean up
  audit: don't reset working wait time accidentally with auditd
  audit: don't lose set wait time on first successful call to audit_log_start()
  audit: move the tree pruning to a dedicated thread
2015-04-22 14:49:23 -07:00
David Howells 3b362157b2 VFS: audit: d_backing_inode() annotations
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15 15:06:55 -04:00
Pranith Kumar 724e7bfcc5 audit: Remove condition which always evaluates to false
After commit 3e1d0bb622 ("audit: Convert int limit
uses to u32"), by converting an int to u32, few conditions will always evaluate
to false.

These warnings were emitted during compilation:

kernel/audit.c: In function ‘audit_set_enabled’:
kernel/audit.c:347:2: warning: comparison of unsigned expression < 0 is always
false [-Wtype-limits]
  if (state < AUDIT_OFF || state > AUDIT_LOCKED)
	  ^
	  kernel/audit.c: In function ‘audit_receive_msg’:
	  kernel/audit.c:880:9: warning: comparison of unsigned expression < 0 is
	  always false [-Wtype-limits]
	      if (s.backlog_wait_time < 0 ||

The following patch removes those unnecessary conditions.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-03-13 17:32:52 -04:00
Davidlohr Bueso 5b28255278 audit: reduce mmap_sem hold for mm->exe_file
The mm->exe_file is currently serialized with mmap_sem (shared)
in order to both safely (1) read the file and (2) audit it via
audit_log_d_path(). Good users will, on the other hand, make use
of the more standard get_mm_exe_file(), requiring only holding
the mmap_sem to read the value, and relying on reference counting
to make sure that the exe file won't dissapear underneath us.

Additionally, upon NULL return of get_mm_exe_file, we also call
audit_log_format(ab, " exe=(null)").

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
[PM: tweaked subject line]
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-02-23 16:57:00 -05:00