Commit Graph

1619 Commits

Author SHA1 Message Date
Linus Torvalds 39e16d9342 selinux/stable-5.7 PR 20200430
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Merge tag 'selinux-pr-20200430' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

Pull SELinux fixes from Paul Moore:
 "Two more SELinux patches to fix problems in the v5.7-rcX releases.

  Wei Yongjun's patch fixes a return code in an error path, and my patch
  fixes a problem where we were not correctly applying access controls
  to all of the netlink messages in the netlink_send LSM hook"

* tag 'selinux-pr-20200430' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: properly handle multiple messages in selinux_netlink_send()
  selinux: fix error return code in cond_read_list()
2020-04-30 16:35:45 -07:00
Paul Moore fb73974172 selinux: properly handle multiple messages in selinux_netlink_send()
Fix the SELinux netlink_send hook to properly handle multiple netlink
messages in a single sk_buff; each message is parsed and subject to
SELinux access control.  Prior to this patch, SELinux only inspected
the first message in the sk_buff.

Cc: stable@vger.kernel.org
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-04-30 16:18:37 -04:00
Wei Yongjun 292fed1fc8 selinux: fix error return code in cond_read_list()
Fix to return negative error code -ENOMEM from the error handling
case instead of 0, as done elsewhere in this function.

Fixes: 60abd3181d ("selinux: convert cond_list to array")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-04-27 17:44:39 -04:00
Linus Torvalds 9786cab674 selinux/stable-5.7 PR 20200416
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Merge tag 'selinux-pr-20200416' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

Pull SELinux fix from Paul Moore:
 "One small SELinux fix to ensure we cleanup properly on an error
  condition"

* tag 'selinux-pr-20200416' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: free str on error in str_read()
2020-04-16 10:45:47 -07:00
Ondrej Mosnacek af15f14c8c selinux: free str on error in str_read()
In [see "Fixes:"] I missed the fact that str_read() may give back an
allocated pointer even if it returns an error, causing a potential
memory leak in filename_trans_read_one(). Fix this by making the
function free the allocated string whenever it returns a non-zero value,
which also makes its behavior more obvious and prevents repeating the
same mistake in the future.

Reported-by: coverity-bot <keescook+coverity-bot@chromium.org>
Addresses-Coverity-ID: 1461665 ("Resource leaks")
Fixes: c3a276111e ("selinux: optimize storage of filename transitions")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-04-15 17:23:16 -04:00
Linus Torvalds ff2ae607c6 SPDX patches for 5.7-rc1.
Here are 3 SPDX patches for 5.7-rc1.
 
 One fixes up the SPDX tag for a single driver, while the other two go
 through the tree and add SPDX tags for all of the .gitignore files as
 needed.
 
 Nothing too complex, but you will get a merge conflict with your current
 tree, that should be trivial to handle (one file modified by two things,
 one file deleted.)
 
 All 3 of these have been in linux-next for a while, with no reported
 issues other than the merge conflict.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx

Pull SPDX updates from Greg KH:
 "Here are three SPDX patches for 5.7-rc1.

  One fixes up the SPDX tag for a single driver, while the other two go
  through the tree and add SPDX tags for all of the .gitignore files as
  needed.

  Nothing too complex, but you will get a merge conflict with your
  current tree, that should be trivial to handle (one file modified by
  two things, one file deleted.)

  All three of these have been in linux-next for a while, with no
  reported issues other than the merge conflict"

* tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
  ASoC: MT6660: make spdxcheck.py happy
  .gitignore: add SPDX License Identifier
  .gitignore: remove too obvious comments
2020-04-03 13:12:26 -07:00
Linus Torvalds b3aa112d57 selinux/stable-5.7 PR 20200330
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Merge tag 'selinux-pr-20200330' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

Pull SELinux updates from Paul Moore:
 "We've got twenty SELinux patches for the v5.7 merge window, the
  highlights are below:

   - Deprecate setting /sys/fs/selinux/checkreqprot to 1.

     This flag was originally created to deal with legacy userspace and
     the READ_IMPLIES_EXEC personality flag. We changed the default from
     1 to 0 back in Linux v4.4 and now we are taking the next step of
     deprecating it, at some point in the future we will take the final
     step of rejecting 1.

   - Allow kernfs symlinks to inherit the SELinux label of the parent
     directory. In order to preserve backwards compatibility this is
     protected by the genfs_seclabel_symlinks SELinux policy capability.

   - Optimize how we store filename transitions in the kernel, resulting
     in some significant improvements to policy load times.

   - Do a better job calculating our internal hash table sizes which
     resulted in additional policy load improvements and likely general
     SELinux performance improvements as well.

   - Remove the unused initial SIDs (labels) and improve how we handle
     initial SIDs.

   - Enable per-file labeling for the bpf filesystem.

   - Ensure that we properly label NFS v4.2 filesystems to avoid a
     temporary unlabeled condition.

   - Add some missing XFS quota command types to the SELinux quota
     access controls.

   - Fix a problem where we were not updating the seq_file position
     index correctly in selinuxfs.

   - We consolidate some duplicated code into helper functions.

   - A number of list to array conversions.

   - Update Stephen Smalley's email address in MAINTAINERS"

* tag 'selinux-pr-20200330' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: clean up indentation issue with assignment statement
  NFS: Ensure security label is set for root inode
  MAINTAINERS: Update my email address
  selinux: avtab_init() and cond_policydb_init() return void
  selinux: clean up error path in policydb_init()
  selinux: remove unused initial SIDs and improve handling
  selinux: reduce the use of hard-coded hash sizes
  selinux: Add xfs quota command types
  selinux: optimize storage of filename transitions
  selinux: factor out loop body from filename_trans_read()
  security: selinux: allow per-file labeling for bpffs
  selinux: generalize evaluate_cond_node()
  selinux: convert cond_expr to array
  selinux: convert cond_av_list to array
  selinux: convert cond_list to array
  selinux: sel_avc_get_stat_idx should increase position index
  selinux: allow kernfs symlinks to inherit parent directory context
  selinux: simplify evaluate_cond_node()
  Documentation,selinux: deprecate setting checkreqprot to 1
  selinux: move status variables out of selinux_ss
2020-03-31 15:07:55 -07:00
Colin Ian King c753924b62 selinux: clean up indentation issue with assignment statement
The assignment of e->type_names is indented one level too deep,
clean this up by removing the extraneous tab.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-03-30 19:57:07 -04:00
Masahiro Yamada d198b34f38 .gitignore: add SPDX License Identifier
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 11:50:48 +01:00
Paul Moore 5e729e111e selinux: avtab_init() and cond_policydb_init() return void
The avtab_init() and cond_policydb_init() functions always return
zero so mark them as returning void and update the callers not to
check for a return value.

Suggested-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-03-05 14:55:43 -05:00
Ondrej Mosnacek 34a2dab488 selinux: clean up error path in policydb_init()
Commit e0ac568de1 ("selinux: reduce the use of hard-coded hash sizes")
moved symtab initialization out of policydb_init(), but left the cleanup
of symtabs from the error path. This patch fixes the oversight.

Suggested-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-03-05 14:49:15 -05:00
Stephen Smalley e3e0b582c3 selinux: remove unused initial SIDs and improve handling
Remove initial SIDs that have never been used or are no longer used by
the kernel from its string table, which is also used to generate the
SECINITSID_* symbols referenced in code.  Update the code to
gracefully handle the fact that these can now be NULL. Stop treating
it as an error if a policy defines additional initial SIDs unknown to
the kernel.  Do not load unused initial SID contexts into the sidtab.
Fix the incorrect usage of the name from the ocontext in error
messages when loading initial SIDs since these are not presently
written to the kernel policy and are therefore always NULL.

After this change, it is possible to safely reclaim and reuse some of
the unused initial SIDs without compatibility issues.  Specifically,
unused initial SIDs that were being assigned the same context as the
unlabeled initial SID in policies can be reclaimed and reused for
another purpose, with existing policies still treating them as having
the unlabeled context and future policies having the option of mapping
them to a more specific context.  For example, this could have been
used when the infiniband labeling support was introduced to define
initial SIDs for the default pkey and endport SIDs similar to the
handling of port/netif/node SIDs rather than always using
SECINITSID_UNLABELED as the default.

The set of safely reclaimable unused initial SIDs across all known
policies is igmp_packet (13), icmp_socket (14), tcp_socket (15), kmod
(24), policy (25), and scmp_packet (26); these initial SIDs were
assigned the same context as unlabeled in all known policies including
mls.  If only considering non-mls policies (i.e. assuming that mls
users always upgrade policy with their kernels), the set of safely
reclaimable unused initial SIDs further includes file_labels (6), init
(7), sysctl_modprobe (16), and sysctl_fs (18) through sysctl_dev (23).

Adding new initial SIDs beyond SECINITSID_NUM to policy unfortunately
became a fatal error in commit 24ed7fdae6 ("selinux: use separate
table for initial SID lookup") and even before that it could cause
problems on a policy reload (collision between the new initial SID and
one allocated at runtime) ever since commit 42596eafdd ("selinux:
load the initial SIDs upon every policy load") so we cannot safely
start adding new initial SIDs to policies beyond SECINITSID_NUM (27)
until such a time as all such kernels do not need to be supported and
only those that include this commit are relevant. That is not a big
deal since we haven't added a new initial SID since 2004 (v2.6.7) and
we have plenty of unused ones we can reclaim if we truly need one.

If we want to avoid the wasted storage in initial_sid_to_string[]
and/or sidtab->isids[] for the unused initial SIDs, we could introduce
an indirection between the kernel initial SID values and the policy
initial SID values and just map the policy SID values in the ocontexts
to the kernel values during policy_load_isids(). Originally I thought
we'd do this by preserving the initial SID names in the kernel policy
and creating a mapping at load time like we do for the security
classes and permissions but that would require a new kernel policy
format version and associated changes to libsepol/checkpolicy and I'm
not sure it is justified. Simpler approach is just to create a fixed
mapping table in the kernel from the existing fixed policy values to
the kernel values. Less flexible but probably sufficient.

A separate selinux userspace change was applied in
8677ce5e8f
to enable removal of most of the unused initial SID contexts from
policies, but there is no dependency between that change and this one.
That change permits removing all of the unused initial SID contexts
from policy except for the fs and sysctl SID contexts.  The initial
SID declarations themselves would remain in policy to preserve the
values of subsequent ones but the contexts can be dropped.  If/when
the kernel decides to reuse one of them, future policies can change
the name and start assigning a context again without breaking
compatibility.

Here is how I would envision staging changes to the initial SIDs in a
compatible manner after this commit is applied:

1. At any time after this commit is applied, the kernel could choose
to reclaim one of the safely reclaimable unused initial SIDs listed
above for a new purpose (i.e. replace its NULL entry in the
initial_sid_to_string[] table with a new name and start using the
newly generated SECINITSID_name symbol in code), and refpolicy could
at that time rename its declaration of that initial SID to reflect its
new purpose and start assigning it a context going
forward. Existing/old policies would map the reclaimed initial SID to
the unlabeled context, so that would be the initial default behavior
until policies are updated. This doesn't depend on the selinux
userspace change; it will work with existing policies and userspace.

2. In 6 months or so we'll have another SELinux userspace release that
will include the libsepol/checkpolicy support for omitting unused
initial SID contexts.

3. At any time after that release, refpolicy can make that release its
minimum build requirement and drop the sid context statements (but not
the sid declarations) for all of the unused initial SIDs except for
fs and sysctl, which must remain for compatibility on policy
reload with old kernels and for compatibility with kernels that were
still using SECINITSID_SYSCTL (< 2.6.39). This doesn't depend on this
kernel commit; it will work with previous kernels as well.

4. After N years for some value of N, refpolicy decides that it no
longer cares about policy reload compatibility for kernels that
predate this kernel commit, and refpolicy drops the fs and sysctl
SID contexts from policy too (but retains the declarations).

5. After M years for some value of M, the kernel decides that it no
longer cares about compatibility with refpolicies that predate step 4
(dropping the fs and sysctl SIDs), and those two SIDs also become
safely reclaimable.  This step is optional and need not ever occur unless
we decide that the need to reclaim those two SIDs outweighs the
compatibility cost.

6. After O years for some value of O, refpolicy decides that it no
longer cares about policy load (not just reload) compatibility for
kernels that predate this kernel commit, and both kernel and refpolicy
can then start adding and using new initial SIDs beyond 27. This does
not depend on the previous change (step 5) and can occur independent
of it.

Fixes: https://github.com/SELinuxProject/selinux-kernel/issues/12
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-27 19:34:24 -05:00
Ondrej Mosnacek e0ac568de1 selinux: reduce the use of hard-coded hash sizes
Instead allocate hash tables with just the right size based on the
actual number of elements (which is almost always known beforehand, we
just need to defer the hashtab allocation to the right time). The only
case when we don't know the size (with the current policy format) is the
new filename transitions hashtable. Here I just left the existing value.

After this patch, the time to load Fedora policy on x86_64 decreases
from 790 ms to 167 ms. If the unconfined module is removed, it decreases
from 750 ms to 122 ms. It is also likely that other operations are going
to be faster, mainly string_to_context_struct() or mls_compute_sid(),
but I didn't try to quantify that.

The memory usage of all hash table arrays increases from ~58 KB to
~163 KB (with Fedora policy on x86_64).

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-27 19:23:20 -05:00
Richard Haines e4cfa05e9b selinux: Add xfs quota command types
Add Q_XQUOTAOFF, Q_XQUOTAON and Q_XSETQLIM to trigger filesystem quotamod
permission check.

Add Q_XGETQUOTA, Q_XGETQSTAT, Q_XGETQSTATV and Q_XGETNEXTQUOTA to trigger
filesystem quotaget permission check.

Signed-off-by: Richard Haines <richard_c_haines@btinternet.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-22 14:41:21 -05:00
Ondrej Mosnacek c3a276111e selinux: optimize storage of filename transitions
In these rules, each rule with the same (target type, target class,
filename) values is (in practice) always mapped to the same result type.
Therefore, it is much more efficient to group the rules by (ttype,
tclass, filename).

Thus, this patch drops the stype field from the key and changes the
datum to be a linked list of one or more structures that contain a
result type and an ebitmap of source types that map the given target to
the given result type under the given filename. The size of the hash
table is also incremented to 2048 to be more optimal for Fedora policy
(which currently has ~2500 unique (ttype, tclass, filename) tuples,
regardless of whether the 'unconfined' module is enabled).

Not only does this dramtically reduce memory usage when the policy
contains a lot of unconfined domains (ergo a lot of filename based
transitions), but it also slightly reduces memory usage of strongly
confined policies (modeled on Fedora policy with 'unconfined' module
disabled) and significantly reduces lookup times of these rules on
Fedora (roughly matches the performance of the rhashtable conversion
patch [1] posted recently to selinux@vger.kernel.org).

An obvious next step is to change binary policy format to match this
layout, so that disk space is also saved. However, since that requires
more work (including matching userspace changes) and this patch is
already beneficial on its own, I'm posting it separately.

Performance/memory usage comparison:

Kernel           | Policy load | Policy load   | Mem usage | Mem usage     | openbench
                 |             | (-unconfined) |           | (-unconfined) | (createfiles)
-----------------|-------------|---------------|-----------|---------------|--------------
reference        |       1,30s |         0,91s |      90MB |          77MB | 55 us/file
rhashtable patch |       0.98s |         0,85s |      85MB |          75MB | 38 us/file
this patch       |       0,95s |         0,87s |      75MB |          75MB | 40 us/file

(Memory usage is measured after boot. With SELinux disabled the memory
usage was ~60MB on the same system.)

[1] https://lore.kernel.org/selinux/20200116213937.77795-1-dev@lynxeye.de/T/

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-22 11:22:32 -05:00
Ondrej Mosnacek 253050f57c selinux: factor out loop body from filename_trans_read()
It simplifies cleanup in the error path. This will be extra useful in
later patch.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-13 18:08:15 -05:00
Connor O'Brien 4ca54d3d30 security: selinux: allow per-file labeling for bpffs
Add support for genfscon per-file labeling of bpffs files. This allows
for separate permissions for different pinned bpf objects, which may
be completely unrelated to each other.

Signed-off-by: Connor O'Brien <connoro@google.com>
Signed-off-by: Steven Moreland <smoreland@google.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-11 22:02:54 -05:00
Ondrej Mosnacek 89d4d7c88d selinux: generalize evaluate_cond_node()
Both callers iterate the cond_list and call it for each node - turn it
into evaluate_cond_nodes(), which does the iteration for them.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-11 21:50:26 -05:00
Ondrej Mosnacek 8794d78390 selinux: convert cond_expr to array
Since it is fixed-size after allocation and we know the size beforehand,
using a plain old array is simpler and more efficient.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-11 21:48:50 -05:00
Ondrej Mosnacek 2b3a003e15 selinux: convert cond_av_list to array
Since it is fixed-size after allocation and we know the size beforehand,
using a plain old array is simpler and more efficient.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-11 21:42:27 -05:00
Ondrej Mosnacek 60abd3181d selinux: convert cond_list to array
Since it is fixed-size after allocation and we know the size beforehand,
using a plain old array is simpler and more efficient.

While there, also fix signedness of some related variables/parameters.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-11 21:39:41 -05:00
Linus Torvalds a5650acb5f selinux/stable-5.6 PR 20200210
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Merge tag 'selinux-pr-20200210' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

Pull SELinux fixes from Paul Moore:
 "Two small fixes: one fixes a locking problem in the recently merged
  label translation code, the other fixes an embarrassing 'binderfs' /
  'binder' filesystem name check"

* tag 'selinux-pr-20200210' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: fix sidtab string cache locking
  selinux: fix typo in filesystem name
2020-02-10 16:51:35 -08:00
Vasily Averin 8d269a8e2a selinux: sel_avc_get_stat_idx should increase position index
If seq_file .next function does not change position index,
read after some lseek can generate unexpected output.

$ dd if=/sys/fs/selinux/avc/cache_stats # usual output
lookups hits misses allocations reclaims frees
817223 810034 7189 7189 6992 7037
1934894 1926896 7998 7998 7632 7683
1322812 1317176 5636 5636 5456 5507
1560571 1551548 9023 9023 9056 9115
0+1 records in
0+1 records out
189 bytes copied, 5,1564e-05 s, 3,7 MB/s

$# read after lseek to midle of last line
$ dd if=/sys/fs/selinux/avc/cache_stats bs=180 skip=1
dd: /sys/fs/selinux/avc/cache_stats: cannot skip to specified offset
056 9115   <<<< end of last line
1560571 1551548 9023 9023 9056 9115  <<< whole last line once again
0+1 records in
0+1 records out
45 bytes copied, 8,7221e-05 s, 516 kB/s

$# read after lseek beyond  end of of file
$ dd if=/sys/fs/selinux/avc/cache_stats bs=1000 skip=1
dd: /sys/fs/selinux/avc/cache_stats: cannot skip to specified offset
1560571 1551548 9023 9023 9056 9115  <<<< generates whole last line
0+1 records in
0+1 records out
36 bytes copied, 9,0934e-05 s, 396 kB/s

https://bugzilla.kernel.org/show_bug.cgi?id=206283

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-10 10:49:01 -05:00
Christian Göttsche 7470d0d13f selinux: allow kernfs symlinks to inherit parent directory context
Currently symlinks on kernel filesystems, like sysfs, are labeled on
creation with the parent filesystem root sid.

Allow symlinks to inherit the parent directory context, so fine-grained
kernfs labeling can be applied to symlinks too and checking contexts
doesn't complain about them.

For backward-compatibility this behavior is contained in a new policy
capability: genfs_seclabel_symlinks

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-10 10:49:01 -05:00
Ondrej Mosnacek 06c2efe2cf selinux: simplify evaluate_cond_node()
It never fails, so it can just return void.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-10 10:49:01 -05:00
Stephen Smalley e9c38f9fc2 Documentation,selinux: deprecate setting checkreqprot to 1
Deprecate setting the SELinux checkreqprot tunable to 1 via kernel
parameter or /sys/fs/selinux/checkreqprot.  Setting it to 0 is left
intact for compatibility since Android and some Linux distributions
do so for security and treat an inability to set it as a fatal error.
Eventually setting it to 0 will become a no-op and the kernel will
stop using checkreqprot's value internally altogether.

checkreqprot was originally introduced as a compatibility mechanism
for legacy userspace and the READ_IMPLIES_EXEC personality flag.
However, if set to 1, it weakens security by allowing mappings to be
made executable without authorization by policy.  The default value
for the SECURITY_SELINUX_CHECKREQPROT_VALUE config option was changed
from 1 to 0 in commit 2a35d196c1 ("selinux: change
CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE default") and both Android
and Linux distributions began explicitly setting
/sys/fs/selinux/checkreqprot to 0 some time ago.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-10 10:49:01 -05:00
Ondrej Mosnacek 4b36cb773a selinux: move status variables out of selinux_ss
It fits more naturally in selinux_state, since it reflects also global
state (the enforcing and policyload fields).

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-10 10:49:01 -05:00
Linus Torvalds c9d35ee049 Merge branch 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs file system parameter updates from Al Viro:
 "Saner fs_parser.c guts and data structures. The system-wide registry
  of syntax types (string/enum/int32/oct32/.../etc.) is gone and so is
  the horror switch() in fs_parse() that would have to grow another case
  every time something got added to that system-wide registry.

  New syntax types can be added by filesystems easily now, and their
  namespace is that of functions - not of system-wide enum members. IOW,
  they can be shared or kept private and if some turn out to be widely
  useful, we can make them common library helpers, etc., without having
  to do anything whatsoever to fs_parse() itself.

  And we already get that kind of requests - the thing that finally
  pushed me into doing that was "oh, and let's add one for timeouts -
  things like 15s or 2h". If some filesystem really wants that, let them
  do it. Without somebody having to play gatekeeper for the variants
  blessed by direct support in fs_parse(), TYVM.

  Quite a bit of boilerplate is gone. And IMO the data structures make a
  lot more sense now. -200LoC, while we are at it"

* 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (25 commits)
  tmpfs: switch to use of invalfc()
  cgroup1: switch to use of errorfc() et.al.
  procfs: switch to use of invalfc()
  hugetlbfs: switch to use of invalfc()
  cramfs: switch to use of errofc() et.al.
  gfs2: switch to use of errorfc() et.al.
  fuse: switch to use errorfc() et.al.
  ceph: use errorfc() and friends instead of spelling the prefix out
  prefix-handling analogues of errorf() and friends
  turn fs_param_is_... into functions
  fs_parse: handle optional arguments sanely
  fs_parse: fold fs_parameter_desc/fs_parameter_spec
  fs_parser: remove fs_parameter_description name field
  add prefix to fs_context->log
  ceph_parse_param(), ceph_parse_mon_ips(): switch to passing fc_log
  new primitive: __fs_parse()
  switch rbd and libceph to p_log-based primitives
  struct p_log, variants of warnf() et.al. taking that one instead
  teach logfc() to handle prefices, give it saner calling conventions
  get rid of cg_invalf()
  ...
2020-02-08 13:26:41 -08:00
Al Viro d7167b1499 fs_parse: fold fs_parameter_desc/fs_parameter_spec
The former contains nothing but a pointer to an array of the latter...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 14:48:37 -05:00
Eric Sandeen 96cafb9ccb fs_parser: remove fs_parameter_description name field
Unused now.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 14:48:36 -05:00
Ondrej Mosnacek 39a706fbcf selinux: fix sidtab string cache locking
Avoiding taking a lock in an IRQ context is not enough to prevent
deadlocks, as discovered by syzbot:

===
WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
5.5.0-syzkaller #0 Not tainted
-----------------------------------------------------
syz-executor.0/8927 [HC0[0]:SC0[2]:HE1:SE0] is trying to acquire:
ffff888027c94098 (&(&s->cache_lock)->rlock){+.+.}, at: spin_lock include/linux/spinlock.h:338 [inline]
ffff888027c94098 (&(&s->cache_lock)->rlock){+.+.}, at: sidtab_sid2str_put.part.0+0x36/0x880 security/selinux/ss/sidtab.c:533

and this task is already holding:
ffffffff898639b0 (&(&nf_conntrack_locks[i])->rlock){+.-.}, at: spin_lock include/linux/spinlock.h:338 [inline]
ffffffff898639b0 (&(&nf_conntrack_locks[i])->rlock){+.-.}, at: nf_conntrack_lock+0x17/0x70 net/netfilter/nf_conntrack_core.c:91
which would create a new lock dependency:
 (&(&nf_conntrack_locks[i])->rlock){+.-.} -> (&(&s->cache_lock)->rlock){+.+.}

but this new dependency connects a SOFTIRQ-irq-safe lock:
 (&(&nf_conntrack_locks[i])->rlock){+.-.}

[...]

other info that might help us debug this:

 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&(&s->cache_lock)->rlock);
                               local_irq_disable();
                               lock(&(&nf_conntrack_locks[i])->rlock);
                               lock(&(&s->cache_lock)->rlock);
  <Interrupt>
    lock(&(&nf_conntrack_locks[i])->rlock);

 *** DEADLOCK ***
[...]
===

Fix this by simply locking with irqsave/irqrestore and stop giving up on
!in_task(). It makes the locking a bit slower, but it shouldn't make a
big difference in real workloads. Under the scenario from [1] (only
cache hits) it only increased the runtime overhead from the
security_secid_to_secctx() function from ~2% to ~3% (it was ~5-65%
before introducing the cache).

[1] https://bugzilla.redhat.com/show_bug.cgi?id=1733259

Fixes: d97bd23c2d ("selinux: cache the SID -> context string translation")
Reported-by: syzbot+61cba5033e2072d61806@syzkaller.appspotmail.com
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-05 18:31:10 -05:00
Hridya Valsaraju a20456aef8 selinux: fix typo in filesystem name
Correct the filesystem name to "binder" to enable genfscon per-file
labelling for binderfs.

Fixes: 7a4b519474 ("selinux: allow per-file labelling for binderfs")
Signed-off-by: Hridya Valsaraju <hridya@google.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: slight style changes to the subj/description]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-05 18:23:13 -05:00
Linus Torvalds bd2463ac7d Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:

 1) Add WireGuard

 2) Add HE and TWT support to ath11k driver, from John Crispin.

 3) Add ESP in TCP encapsulation support, from Sabrina Dubroca.

 4) Add variable window congestion control to TIPC, from Jon Maloy.

 5) Add BCM84881 PHY driver, from Russell King.

 6) Start adding netlink support for ethtool operations, from Michal
    Kubecek.

 7) Add XDP drop and TX action support to ena driver, from Sameeh
    Jubran.

 8) Add new ipv4 route notifications so that mlxsw driver does not have
    to handle identical routes itself. From Ido Schimmel.

 9) Add BPF dynamic program extensions, from Alexei Starovoitov.

10) Support RX and TX timestamping in igc, from Vinicius Costa Gomes.

11) Add support for macsec HW offloading, from Antoine Tenart.

12) Add initial support for MPTCP protocol, from Christoph Paasch,
    Matthieu Baerts, Florian Westphal, Peter Krystad, and many others.

13) Add Octeontx2 PF support, from Sunil Goutham, Geetha sowjanya, Linu
    Cherian, and others.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1469 commits)
  net: phy: add default ARCH_BCM_IPROC for MDIO_BCM_IPROC
  udp: segment looped gso packets correctly
  netem: change mailing list
  qed: FW 8.42.2.0 debug features
  qed: rt init valid initialization changed
  qed: Debug feature: ilt and mdump
  qed: FW 8.42.2.0 Add fw overlay feature
  qed: FW 8.42.2.0 HSI changes
  qed: FW 8.42.2.0 iscsi/fcoe changes
  qed: Add abstraction for different hsi values per chip
  qed: FW 8.42.2.0 Additional ll2 type
  qed: Use dmae to write to widebus registers in fw_funcs
  qed: FW 8.42.2.0 Parser offsets modified
  qed: FW 8.42.2.0 Queue Manager changes
  qed: FW 8.42.2.0 Expose new registers and change windows
  qed: FW 8.42.2.0 Internal ram offsets modifications
  MAINTAINERS: Add entry for Marvell OcteonTX2 Physical Function driver
  Documentation: net: octeontx2: Add RVU HW and drivers overview
  octeontx2-pf: ethtool RSS config support
  octeontx2-pf: Add basic ethtool support
  ...
2020-01-28 16:02:33 -08:00
Stephen Smalley 98aa00345d selinux: fix regression introduced by move_mount(2) syscall
commit 2db154b3ea ("vfs: syscall: Add move_mount(2) to move mounts around")
introduced a new move_mount(2) system call and a corresponding new LSM
security_move_mount hook but did not implement this hook for any existing
LSM.  This creates a regression for SELinux with respect to consistent
checking of mounts; the existing selinux_mount hook checks mounton
permission to the mount point path.  Provide a SELinux hook
implementation for move_mount that applies this same check for
consistency.  In the future we may wish to add a new move_mount
filesystem permission and check as well, but this addresses
the immediate regression.

Fixes: 2db154b3ea ("vfs: syscall: Add move_mount(2) to move mounts around")
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-20 07:42:37 -05:00
Ondrej Mosnacek dd89b9d9f3 selinux: do not allocate ancillary buffer on first load
In security_load_policy(), we can defer allocating the newpolicydb
ancillary array to after checking state->initialized, thereby avoiding
the pointless allocation when loading policy the first time.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
[PM: merged portions by hand]
Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-16 16:05:25 -05:00
Paul Moore cb89e24658 selinux: remove redundant allocation and helper functions
This patch removes the inode, file, and superblock security blob
allocation functions and moves the associated code into the
respective LSM hooks.  This patch also removes the inode_doinit()
function as it was a trivial wrapper around
inode_doinit_with_dentry() and called from one location in the code.

Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-16 14:38:03 -05:00
Huaisheng Ye df4779b5d2 selinux: remove redundant selinux_nlmsg_perm
selinux_nlmsg_perm is used for only by selinux_netlink_send. Remove
the redundant function to simplify the code.

Fix a typo by suggestion from Stephen.

Signed-off-by: Huaisheng Ye <yehs1@lenovo.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-16 14:34:36 -05:00
Ondrej Mosnacek ae3d8c2e27 selinux: fix wrong buffer types in policydb.c
Two places used u32 where there should have been __le32.

Fixes sparse warnings:
  CHECK   [...]/security/selinux/ss/services.c
[...]/security/selinux/ss/policydb.c:2669:16: warning: incorrect type in assignment (different base types)
[...]/security/selinux/ss/policydb.c:2669:16:    expected unsigned int
[...]/security/selinux/ss/policydb.c:2669:16:    got restricted __le32 [usertype]
[...]/security/selinux/ss/policydb.c:2674:24: warning: incorrect type in assignment (different base types)
[...]/security/selinux/ss/policydb.c:2674:24:    expected unsigned int
[...]/security/selinux/ss/policydb.c:2674:24:    got restricted __le32 [usertype]
[...]/security/selinux/ss/policydb.c:2675:24: warning: incorrect type in assignment (different base types)
[...]/security/selinux/ss/policydb.c:2675:24:    expected unsigned int
[...]/security/selinux/ss/policydb.c:2675:24:    got restricted __le32 [usertype]
[...]/security/selinux/ss/policydb.c:2676:24: warning: incorrect type in assignment (different base types)
[...]/security/selinux/ss/policydb.c:2676:24:    expected unsigned int
[...]/security/selinux/ss/policydb.c:2676:24:    got restricted __le32 [usertype]
[...]/security/selinux/ss/policydb.c:2681:32: warning: incorrect type in assignment (different base types)
[...]/security/selinux/ss/policydb.c:2681:32:    expected unsigned int
[...]/security/selinux/ss/policydb.c:2681:32:    got restricted __le32 [usertype]
[...]/security/selinux/ss/policydb.c:2701:16: warning: incorrect type in assignment (different base types)
[...]/security/selinux/ss/policydb.c:2701:16:    expected unsigned int
[...]/security/selinux/ss/policydb.c:2701:16:    got restricted __le32 [usertype]
[...]/security/selinux/ss/policydb.c:2706:24: warning: incorrect type in assignment (different base types)
[...]/security/selinux/ss/policydb.c:2706:24:    expected unsigned int
[...]/security/selinux/ss/policydb.c:2706:24:    got restricted __le32 [usertype]
[...]/security/selinux/ss/policydb.c:2707:24: warning: incorrect type in assignment (different base types)
[...]/security/selinux/ss/policydb.c:2707:24:    expected unsigned int
[...]/security/selinux/ss/policydb.c:2707:24:    got restricted __le32 [usertype]

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-16 14:31:05 -05:00
Nikolay Aleksandrov 8dcea18708 net: bridge: vlan: add rtm definitions and dump support
This patch adds vlan rtm definitions:
 - NEWVLAN: to be used for creating vlans, setting options and
   notifications
 - DELVLAN: to be used for deleting vlans
 - GETVLAN: used for dumping vlan information

Dumping vlans which can span multiple messages is added now with basic
information (vid and flags). We use nlmsg_parse() to validate the header
length in order to be able to extend the message with filtering
attributes later.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-15 13:48:17 +01:00
Ondrej Mosnacek cfff75d897 selinux: reorder hooks to make runtime disable less broken
Commit b1d9e6b064 ("LSM: Switch to lists of hooks") switched the LSM
infrastructure to use per-hook lists, which meant that removing the
hooks for a given module was no longer atomic. Even though the commit
clearly documents that modules implementing runtime revmoval of hooks
(only SELinux attempts this madness) need to take special precautions to
avoid race conditions, SELinux has never addressed this.

By inserting an artificial delay between the loop iterations of
security_delete_hooks() (I used 100 ms), booting to a state where
SELinux is enabled, but policy is not yet loaded, and running these
commands:

    while true; do ping -c 1 <some IP>; done &
    echo -n 1 >/sys/fs/selinux/disable
    kill %1
    wait

...I was able to trigger NULL pointer dereferences in various places. I
also have a report of someone getting panics on a stock RHEL-8 kernel
after setting SELINUX=disabled in /etc/selinux/config and rebooting
(without adding "selinux=0" to kernel command-line).

Reordering the SELinux hooks such that those that allocate structures
are removed last seems to prevent these panics. It is very much possible
that this doesn't make the runtime disable completely race-free, but at
least it makes the operation much less fragile.

Cc: stable@vger.kernel.org
Fixes: b1d9e6b064 ("LSM: Switch to lists of hooks")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-10 15:26:55 -05:00
Ondrej Mosnacek 65cddd5098 selinux: treat atomic flags more carefully
The disabled/enforcing/initialized flags are all accessed concurrently
by threads so use the appropriate accessors that ensure atomicity and
document that it is expected.

Use smp_load/acquire...() helpers (with memory barriers) for the
initialized flag, since it gates access to the rest of the state
structures.

Note that the disabled flag is currently not used for anything other
than avoiding double disable, but it will be used for bailing out of
hooks once security_delete_hooks() is removed.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-10 15:19:39 -05:00
Stephen Smalley b78b7d59bd selinux: make default_noexec read-only after init
SELinux checks whether VM_EXEC is set in the VM_DATA_DEFAULT_FLAGS
during initialization and saves the result in default_noexec for use
in its mmap and mprotect hook function implementations to decide
whether to apply EXECMEM, EXECHEAP, EXECSTACK, and EXECMOD checks.
Mark default_noexec as ro_after_init to prevent later clearing it
and thereby disabling these checks.  It is only set legitimately from
init code.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-10 12:26:20 -05:00
Ravi Kumar Siddojigari fe49c7e4f8 selinux: move ibpkeys code under CONFIG_SECURITY_INFINIBAND.
Move cache based  pkey sid  retrieval code which was added
with commit "409dcf31" under CONFIG_SECURITY_INFINIBAND.
As its  going to alloc a new cache which impacts
low RAM devices which was enabled by default.

Suggested-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Ravi Kumar Siddojigari <rsiddoji@codeaurora.org>
[PM: checkpatch.pl cleanups, fixed capitalization in the description]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-10 11:56:37 -05:00
Huaisheng Ye b82f3f6894 selinux: remove redundant msg_msg_alloc_security
selinux_msg_msg_alloc_security only calls msg_msg_alloc_security but
do nothing else. And also msg_msg_alloc_security is just used by the
former.

Remove the redundant function to simplify the code.

Signed-off-by: Huaisheng Ye <yehs1@lenovo.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-10 11:32:13 -05:00
Stephen Smalley d41415eb5e Documentation,selinux: fix references to old selinuxfs mount point
selinuxfs was originally mounted on /selinux, and various docs and
kconfig help texts referred to nodes under it.  In Linux 3.0,
/sys/fs/selinux was introduced as the preferred mount point for selinuxfs.
Fix all the old references to /selinux/ to /sys/fs/selinux/.
While we are there, update the description of the selinux boot parameter
to reflect the fact that the default value is always 1 since
commit be6ec88f41 ("selinux: Remove SECURITY_SELINUX_BOOTPARAM_VALUE")
and drop discussion of runtime disable since it is deprecated.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-07 12:46:53 -05:00
Paul Moore 89b223bfb8 selinux: deprecate disabling SELinux and runtime
Deprecate the CONFIG_SECURITY_SELINUX_DISABLE functionality.  The
code was originally developed to make it easier for Linux
distributions to support architectures where adding parameters to the
kernel command line was difficult.  Unfortunately, supporting runtime
disable meant we had to make some security trade-offs when it came to
the LSM hooks, as documented in the Kconfig help text:

  NOTE: selecting this option will disable the '__ro_after_init'
  kernel hardening feature for security hooks.   Please consider
  using the selinux=0 boot parameter instead of enabling this
  option.

Fortunately it looks as if that the original motivation for the
runtime disable functionality is gone, and Fedora/RHEL appears to be
the only major distribution enabling this capability at build time
so we are now taking steps to remove it entirely from the kernel.
The first step is to mark the functionality as deprecated and print
an error when it is used (what this patch is doing).  As Fedora/RHEL
makes progress in transitioning the distribution away from runtime
disable, we will introduce follow-up patches over several kernel
releases which will block for increasing periods of time when the
runtime disable is used.  Finally we will remove the option entirely
once we believe all users have moved to the kernel cmdline approach.

Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-07 10:19:43 -05:00
Hridya Valsaraju 7a4b519474 selinux: allow per-file labelling for binderfs
This patch allows genfscon per-file labeling for binderfs.
This is required to have separate permissions to allow
access to binder, hwbinder and vndbinder devices which are
relocating to binderfs.

Acked-by: Jeff Vander Stoep <jeffv@google.com>
Acked-by: Mark Salyzyn <salyzyn@android.com>
Signed-off-by: Hridya Valsaraju <hridya@google.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-06 21:11:18 -05:00
liuyang34 7e78c87514 selinuxfs: use scnprintf to get real length for inode
The return value of snprintf maybe over the size of TMPBUFLEN, use
scnprintf instead in sel_read_class and sel_read_perm.

Signed-off-by: liuyang34 <liuyang34@xiaomi.com>
[PM: cleaned up the description]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-06 21:05:57 -05:00
YueHaibing f126853402 selinux: remove set but not used variable 'sidtab'
security/selinux/ss/services.c: In function security_port_sid:
security/selinux/ss/services.c:2346:17: warning: variable sidtab set but not used [-Wunused-but-set-variable]
security/selinux/ss/services.c: In function security_ib_endport_sid:
security/selinux/ss/services.c:2435:17: warning: variable sidtab set but not used [-Wunused-but-set-variable]
security/selinux/ss/services.c: In function security_netif_sid:
security/selinux/ss/services.c:2480:17: warning: variable sidtab set but not used [-Wunused-but-set-variable]
security/selinux/ss/services.c: In function security_fs_use:
security/selinux/ss/services.c:2831:17: warning: variable sidtab set but not used [-Wunused-but-set-variable]

Since commit 66f8e2f03c ("selinux: sidtab reverse lookup hash table")
'sidtab' is not used any more, so remove it.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-12-24 14:34:01 -05:00
Paul Moore 15b590a81f selinux: ensure the policy has been loaded before reading the sidtab stats
Check to make sure we have loaded a policy before we query the
sidtab's hash stats.  Failure to do so could result in a kernel
panic/oops due to a dereferenced NULL pointer.

Fixes: 66f8e2f03c ("selinux: sidtab reverse lookup hash table")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-12-23 16:38:36 -05:00