Commit graph

965 commits

Author SHA1 Message Date
John Johansen
13bc277241 apparmor: fix race between freeing data and fs accessing it
commit 8e135b8aee upstream.

AppArmor was putting the reference to i_private data on its end after
removing the original entry from the file system. However the inode
can aand does live beyond that point and it is possible that some of
the fs call back functions will be invoked after the reference has
been put, which results in a race between freeing the data and
accessing it through the fs.

While the rawdata/loaddata is the most likely candidate to fail the
race, as it has the fewest references. If properly crafted it might be
possible to trigger a race for the other types stored in i_private.

Fix this by moving the put of i_private referenced data to the correct
place which is during inode eviction.

Fixes: c961ee5f21 ("apparmor: convert from securityfs to apparmorfs for policy ns files")
Reported-by: Qualys Security Advisory <qsa@qualys.com>
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Reviewed-by: Maxime Bélair <maxime.belair@canonical.com>
Reviewed-by: Cengiz Can <cengiz.can@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-03-13 17:23:30 +01:00
John Johansen
af782cc887 apparmor: fix race on rawdata dereference
commit a0b7091c4d upstream.

There is a race condition that leads to a use-after-free situation:
because the rawdata inodes are not refcounted, an attacker can start
open()ing one of the rawdata files, and at the same time remove the
last reference to this rawdata (by removing the corresponding profile,
for example), which frees its struct aa_loaddata; as a result, when
seq_rawdata_open() is reached, i_private is a dangling pointer and
freed memory is accessed.

The rawdata inodes weren't refcounted to avoid a circular refcount and
were supposed to be held by the profile rawdata reference.  However
during profile removal there is a window where the vfs and profile
destruction race, resulting in the use after free.

Fix this by moving to a double refcount scheme. Where the profile
refcount on rawdata is used to break the circular dependency. Allowing
for freeing of the rawdata once all inode references to the rawdata
are put.

Fixes: 5d5182cae4 ("apparmor: move to per loaddata files, instead of replicating in profiles")
Reported-by: Qualys Security Advisory <qsa@qualys.com>
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Reviewed-by: Maxime Bélair <maxime.belair@canonical.com>
Reviewed-by: Cengiz Can <cengiz.can@canonical.com>
Tested-by: Salvatore Bonaccorso <carnil@debian.org>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-03-13 17:23:29 +01:00
John Johansen
623a9d211b apparmor: fix differential encoding verification
commit 39440b1375 upstream.

Differential encoding allows loops to be created if it is abused. To
prevent this the unpack should verify that a diff-encode chain
terminates.

Unfortunately the differential encode verification had two bugs.

1. it conflated states that had gone through check and already been
   marked, with states that were currently being checked and marked.
   This means that loops in the current chain being verified are treated
   as a chain that has already been verified.

2. the order bailout on already checked states compared current chain
   check iterators j,k instead of using the outer loop iterator i.
   Meaning a step backwards in states in the current chain verification
   was being mistaken for moving to an already verified state.

Move to a double mark scheme where already verified states get a
different mark, than the current chain being kept. This enables us
to also drop the backwards verification check that was the cause of
the second error as any already verified state is already marked.

Fixes: 031dcc8f4e ("apparmor: dfa add support for state differential encoding")
Reported-by: Qualys Security Advisory <qsa@qualys.com>
Tested-by: Salvatore Bonaccorso <carnil@debian.org>
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Reviewed-by: Cengiz Can <cengiz.can@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-03-13 17:23:29 +01:00
John Johansen
b60b3f7a35 apparmor: fix unprivileged local user can do privileged policy management
commit 6601e13e82 upstream.

An unprivileged local user can load, replace, and remove profiles by
opening the apparmorfs interfaces, via a confused deputy attack, by
passing the opened fd to a privileged process, and getting the
privileged process to write to the interface.

This does require a privileged target that can be manipulated to do
the write for the unprivileged process, but once such access is
achieved full policy management is possible and all the possible
implications that implies: removing confinement, DoS of system or
target applications by denying all execution, by-passing the
unprivileged user namespace restriction, to exploiting kernel bugs for
a local privilege escalation.

The policy management interface can not have its permissions simply
changed from 0666 to 0600 because non-root processes need to be able
to load policy to different policy namespaces.

Instead ensure the task writing the interface has privileges that
are a subset of the task that opened the interface. This is already
done via policy for confined processes, but unconfined can delegate
access to the opened fd, by-passing the usual policy check.

Fixes: b7fd2c0340 ("apparmor: add per policy ns .load, .replace, .remove interface files")
Reported-by: Qualys Security Advisory <qsa@qualys.com>
Tested-by: Salvatore Bonaccorso <carnil@debian.org>
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Reviewed-by: Cengiz Can <cengiz.can@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-03-13 17:23:29 +01:00
John Johansen
7998ab3010 apparmor: Fix double free of ns_name in aa_replace_profiles()
commit 5df0c44e8f upstream.

if ns_name is NULL after
1071         error = aa_unpack(udata, &lh, &ns_name);

and if ent->ns_name contains an ns_name in
1089                 } else if (ent->ns_name) {

then ns_name is assigned the ent->ns_name
1095                         ns_name = ent->ns_name;

however ent->ns_name is freed at
1262                 aa_load_ent_free(ent);

and then again when freeing ns_name at
1270         kfree(ns_name);

Fix this by NULLing out ent->ns_name after it is transferred to ns_name

Fixes: 145a0ef21c ("apparmor: fix blob compression when ns is forced on a policy load
")
Reported-by: Qualys Security Advisory <qsa@qualys.com>
Tested-by: Salvatore Bonaccorso <carnil@debian.org>
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Reviewed-by: Cengiz Can <cengiz.can@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-03-13 17:23:29 +01:00
Massimiliano Pellizzer
5a68e46dfe apparmor: fix missing bounds check on DEFAULT table in verify_dfa()
commit d352873bbe upstream.

The verify_dfa() function only checks DEFAULT_TABLE bounds when the state
is not differentially encoded.

When the verification loop traverses the differential encoding chain,
it reads k = DEFAULT_TABLE[j] and uses k as an array index without
validation. A malformed DFA with DEFAULT_TABLE[j] >= state_count,
therefore, causes both out-of-bounds reads and writes.

[   57.179855] ==================================================================
[   57.180549] BUG: KASAN: slab-out-of-bounds in verify_dfa+0x59a/0x660
[   57.180904] Read of size 4 at addr ffff888100eadec4 by task su/993

[   57.181554] CPU: 1 UID: 0 PID: 993 Comm: su Not tainted 6.19.0-rc7-next-20260127 #1 PREEMPT(lazy)
[   57.181558] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[   57.181563] Call Trace:
[   57.181572]  <TASK>
[   57.181577]  dump_stack_lvl+0x5e/0x80
[   57.181596]  print_report+0xc8/0x270
[   57.181605]  ? verify_dfa+0x59a/0x660
[   57.181608]  kasan_report+0x118/0x150
[   57.181620]  ? verify_dfa+0x59a/0x660
[   57.181623]  verify_dfa+0x59a/0x660
[   57.181627]  aa_dfa_unpack+0x1610/0x1740
[   57.181629]  ? __kmalloc_cache_noprof+0x1d0/0x470
[   57.181640]  unpack_pdb+0x86d/0x46b0
[   57.181647]  ? srso_alias_return_thunk+0x5/0xfbef5
[   57.181653]  ? srso_alias_return_thunk+0x5/0xfbef5
[   57.181656]  ? aa_unpack_nameX+0x1a8/0x300
[   57.181659]  aa_unpack+0x20b0/0x4c30
[   57.181662]  ? srso_alias_return_thunk+0x5/0xfbef5
[   57.181664]  ? stack_depot_save_flags+0x33/0x700
[   57.181681]  ? kasan_save_track+0x4f/0x80
[   57.181683]  ? kasan_save_track+0x3e/0x80
[   57.181686]  ? __kasan_kmalloc+0x93/0xb0
[   57.181688]  ? __kvmalloc_node_noprof+0x44a/0x780
[   57.181693]  ? aa_simple_write_to_buffer+0x54/0x130
[   57.181697]  ? policy_update+0x154/0x330
[   57.181704]  aa_replace_profiles+0x15a/0x1dd0
[   57.181707]  ? srso_alias_return_thunk+0x5/0xfbef5
[   57.181710]  ? __kvmalloc_node_noprof+0x44a/0x780
[   57.181712]  ? aa_loaddata_alloc+0x77/0x140
[   57.181715]  ? srso_alias_return_thunk+0x5/0xfbef5
[   57.181717]  ? _copy_from_user+0x2a/0x70
[   57.181730]  policy_update+0x17a/0x330
[   57.181733]  profile_replace+0x153/0x1a0
[   57.181735]  ? rw_verify_area+0x93/0x2d0
[   57.181740]  vfs_write+0x235/0xab0
[   57.181745]  ksys_write+0xb0/0x170
[   57.181748]  do_syscall_64+0x8e/0x660
[   57.181762]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[   57.181765] RIP: 0033:0x7f6192792eb2

Remove the MATCH_FLAG_DIFF_ENCODE condition to validate all DEFAULT_TABLE
entries unconditionally.

Fixes: 031dcc8f4e ("apparmor: dfa add support for state differential encoding")
Reported-by: Qualys Security Advisory <qsa@qualys.com>
Tested-by: Salvatore Bonaccorso <carnil@debian.org>
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Reviewed-by: Cengiz Can <cengiz.can@canonical.com>
Signed-off-by: Massimiliano Pellizzer <massimiliano.pellizzer@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-03-13 17:23:29 +01:00
Massimiliano Pellizzer
0510d1ba09 apparmor: fix side-effect bug in match_char() macro usage
commit 8756b68eda upstream.

The match_char() macro evaluates its character parameter multiple
times when traversing differential encoding chains. When invoked
with *str++, the string pointer advances on each iteration of the
inner do-while loop, causing the DFA to check different characters
at each iteration and therefore skip input characters.
This results in out-of-bounds reads when the pointer advances past
the input buffer boundary.

[   94.984676] ==================================================================
[   94.985301] BUG: KASAN: slab-out-of-bounds in aa_dfa_match+0x5ae/0x760
[   94.985655] Read of size 1 at addr ffff888100342000 by task file/976

[   94.986319] CPU: 7 UID: 1000 PID: 976 Comm: file Not tainted 6.19.0-rc7-next-20260127 #1 PREEMPT(lazy)
[   94.986322] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[   94.986329] Call Trace:
[   94.986341]  <TASK>
[   94.986347]  dump_stack_lvl+0x5e/0x80
[   94.986374]  print_report+0xc8/0x270
[   94.986384]  ? aa_dfa_match+0x5ae/0x760
[   94.986388]  kasan_report+0x118/0x150
[   94.986401]  ? aa_dfa_match+0x5ae/0x760
[   94.986405]  aa_dfa_match+0x5ae/0x760
[   94.986408]  __aa_path_perm+0x131/0x400
[   94.986418]  aa_path_perm+0x219/0x2f0
[   94.986424]  apparmor_file_open+0x345/0x570
[   94.986431]  security_file_open+0x5c/0x140
[   94.986442]  do_dentry_open+0x2f6/0x1120
[   94.986450]  vfs_open+0x38/0x2b0
[   94.986453]  ? may_open+0x1e2/0x2b0
[   94.986466]  path_openat+0x231b/0x2b30
[   94.986469]  ? __x64_sys_openat+0xf8/0x130
[   94.986477]  do_file_open+0x19d/0x360
[   94.986487]  do_sys_openat2+0x98/0x100
[   94.986491]  __x64_sys_openat+0xf8/0x130
[   94.986499]  do_syscall_64+0x8e/0x660
[   94.986515]  ? count_memcg_events+0x15f/0x3c0
[   94.986526]  ? srso_alias_return_thunk+0x5/0xfbef5
[   94.986540]  ? handle_mm_fault+0x1639/0x1ef0
[   94.986551]  ? vma_start_read+0xf0/0x320
[   94.986558]  ? srso_alias_return_thunk+0x5/0xfbef5
[   94.986561]  ? srso_alias_return_thunk+0x5/0xfbef5
[   94.986563]  ? fpregs_assert_state_consistent+0x50/0xe0
[   94.986572]  ? srso_alias_return_thunk+0x5/0xfbef5
[   94.986574]  ? arch_exit_to_user_mode_prepare+0x9/0xb0
[   94.986587]  ? srso_alias_return_thunk+0x5/0xfbef5
[   94.986588]  ? irqentry_exit+0x3c/0x590
[   94.986595]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[   94.986597] RIP: 0033:0x7fda4a79c3ea

Fix by extracting the character value before invoking match_char,
ensuring single evaluation per outer loop.

Fixes: 074c1cd798 ("apparmor: dfa move character match into a macro")
Reported-by: Qualys Security Advisory <qsa@qualys.com>
Tested-by: Salvatore Bonaccorso <carnil@debian.org>
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Reviewed-by: Cengiz Can <cengiz.can@canonical.com>
Signed-off-by: Massimiliano Pellizzer <massimiliano.pellizzer@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-03-13 17:23:29 +01:00
John Johansen
d42b2b6bb7 apparmor: fix: limit the number of levels of policy namespaces
commit 3060394149 upstream.

Currently the number of policy namespaces is not bounded relying on
the user namespace limit. However policy namespaces aren't strictly
tied to user namespaces and it is possible to create them and nest
them arbitrarily deep which can be used to exhaust system resource.

Hard cap policy namespaces to the same depth as user namespaces.

Fixes: c88d4c7b04 ("AppArmor: core policy routines")
Reported-by: Qualys Security Advisory <qsa@qualys.com>
Reviewed-by: Ryan Lee <ryan.lee@canonical.com>
Reviewed-by: Cengiz Can <cengiz.can@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-03-13 17:23:29 +01:00
Massimiliano Pellizzer
7eade846e0 apparmor: replace recursive profile removal with iterative approach
commit ab09264660 upstream.

The profile removal code uses recursion when removing nested profiles,
which can lead to kernel stack exhaustion and system crashes.

Reproducer:
  $ pf='a'; for ((i=0; i<1024; i++)); do
      echo -e "profile $pf { \n }" | apparmor_parser -K -a;
      pf="$pf//x";
  done
  $ echo -n a > /sys/kernel/security/apparmor/.remove

Replace the recursive __aa_profile_list_release() approach with an
iterative approach in __remove_profile(). The function repeatedly
finds and removes leaf profiles until the entire subtree is removed,
maintaining the same removal semantic without recursion.

Fixes: c88d4c7b04 ("AppArmor: core policy routines")
Reported-by: Qualys Security Advisory <qsa@qualys.com>
Tested-by: Salvatore Bonaccorso <carnil@debian.org>
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Reviewed-by: Cengiz Can <cengiz.can@canonical.com>
Signed-off-by: Massimiliano Pellizzer <massimiliano.pellizzer@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-03-13 17:23:29 +01:00
Massimiliano Pellizzer
4f0889f2df apparmor: fix memory leak in verify_header
commit e38c55d9f8 upstream.

The function sets `*ns = NULL` on every call, leaking the namespace
string allocated in previous iterations when multiple profiles are
unpacked. This also breaks namespace consistency checking since *ns
is always NULL when the comparison is made.

Remove the incorrect assignment.
The caller (aa_unpack) initializes *ns to NULL once before the loop,
which is sufficient.

Fixes: dd51c84857 ("apparmor: provide base for multiple profiles to be replaced at once")
Reported-by: Qualys Security Advisory <qsa@qualys.com>
Tested-by: Salvatore Bonaccorso <carnil@debian.org>
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Reviewed-by: Cengiz Can <cengiz.can@canonical.com>
Signed-off-by: Massimiliano Pellizzer <massimiliano.pellizzer@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-03-13 17:23:28 +01:00
Massimiliano Pellizzer
0baadb0eec apparmor: validate DFA start states are in bounds in unpack_pdb
commit 9063d7e261 upstream.

Start states are read from untrusted data and used as indexes into the
DFA state tables. The aa_dfa_next() function call in unpack_pdb() will
access dfa->tables[YYTD_ID_BASE][start], and if the start state exceeds
the number of states in the DFA, this results in an out-of-bound read.

==================================================================
 BUG: KASAN: slab-out-of-bounds in aa_dfa_next+0x2a1/0x360
 Read of size 4 at addr ffff88811956fb90 by task su/1097
 ...

Reject policies with out-of-bounds start states during unpacking
to prevent the issue.

Fixes: ad5ff3db53 ("AppArmor: Add ability to load extended policy")
Reported-by: Qualys Security Advisory <qsa@qualys.com>
Tested-by: Salvatore Bonaccorso <carnil@debian.org>
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Reviewed-by: Cengiz Can <cengiz.can@canonical.com>
Signed-off-by: Massimiliano Pellizzer <massimiliano.pellizzer@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-03-13 17:23:28 +01:00
John Johansen
aebd195e93 apparmor: fix aa_label to return state from compount and component match
[ Upstream commit 9058798652 ]

aa-label_match is not correctly returning the state in all cases.
The only reason this didn't cause a error is that all callers currently
ignore the return value.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202602020631.wXgZosyU-lkp@intel.com/
Fixes: a4c9efa4db ("apparmor: make label_match return a consistent value")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-26 14:59:42 -08:00
Georgia Garcia
1d2b2b58fd apparmor: fix invalid deref of rawdata when export_binary is unset
[ Upstream commit df9ac55abd ]

If the export_binary parameter is disabled on runtime, profiles that
were loaded before that will still have their rawdata stored in
apparmorfs, with a symbolic link to the rawdata on the policy
directory. When one of those profiles are replaced, the rawdata is set
to NULL, but when trying to resolve the symbolic links to rawdata for
that profile, it will try to dereference profile->rawdata->name when
profile->rawdata is now NULL causing an oops. Fix it by checking if
rawdata is set.

[  168.653080] BUG: kernel NULL pointer dereference, address: 0000000000000088
[  168.657420] #PF: supervisor read access in kernel mode
[  168.660619] #PF: error_code(0x0000) - not-present page
[  168.663613] PGD 0 P4D 0
[  168.665450] Oops: Oops: 0000 [#1] SMP NOPTI
[  168.667836] CPU: 1 UID: 0 PID: 1729 Comm: ls Not tainted 6.19.0-rc7+ #3 PREEMPT(voluntary)
[  168.672308] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[  168.679327] RIP: 0010:rawdata_get_link_base.isra.0+0x23/0x330
[  168.682768] Code: 90 90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 ec 18 48 89 55 d0 48 85 ff 0f 84 e3 01 00 00 <48> 83 3c 25 88 00 00 00 00 0f 84 d4 01 00 00 49 89 f6 49 89 cc e8
[  168.689818] RSP: 0018:ffffcdcb8200fb80 EFLAGS: 00010282
[  168.690871] RAX: ffffffffaee74ec0 RBX: 0000000000000000 RCX: ffffffffb0120158
[  168.692251] RDX: ffffcdcb8200fbe0 RSI: ffff88c187c9fa80 RDI: ffff88c186c98a80
[  168.693593] RBP: ffffcdcb8200fbc0 R08: 0000000000000000 R09: 0000000000000000
[  168.694941] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88c186c98a80
[  168.696289] R13: 00007fff005aaa20 R14: 0000000000000080 R15: ffff88c188f4fce0
[  168.697637] FS:  0000790e81c58280(0000) GS:ffff88c20a957000(0000) knlGS:0000000000000000
[  168.699227] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  168.700349] CR2: 0000000000000088 CR3: 000000012fd3e000 CR4: 0000000000350ef0
[  168.701696] Call Trace:
[  168.702325]  <TASK>
[  168.702995]  rawdata_get_link_data+0x1c/0x30
[  168.704145]  vfs_readlink+0xd4/0x160
[  168.705152]  do_readlinkat+0x114/0x180
[  168.706214]  __x64_sys_readlink+0x1e/0x30
[  168.708653]  x64_sys_call+0x1d77/0x26b0
[  168.709525]  do_syscall_64+0x81/0x500
[  168.710348]  ? do_statx+0x72/0xb0
[  168.711109]  ? putname+0x3e/0x80
[  168.711845]  ? __x64_sys_statx+0xb7/0x100
[  168.712711]  ? x64_sys_call+0x10fc/0x26b0
[  168.713577]  ? do_syscall_64+0xbf/0x500
[  168.714412]  ? do_user_addr_fault+0x1d2/0x8d0
[  168.715404]  ? irqentry_exit+0xb2/0x740
[  168.716359]  ? exc_page_fault+0x90/0x1b0
[  168.717307]  entry_SYSCALL_64_after_hwframe+0x76/0x7e

Fixes: 1180b4c757 ("apparmor: fix dangling symlinks to policy rawdata after replacement")
Signed-off-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-26 14:59:42 -08:00
Zhengmian Hu
80c334acc6 apparmor: avoid per-cpu hold underflow in aa_get_buffer
[ Upstream commit 640cf2f095 ]

When aa_get_buffer() pulls from the per-cpu list it unconditionally
decrements cache->hold. If hold reaches 0 while count is still non-zero,
the unsigned decrement wraps to UINT_MAX. This keeps hold non-zero for a
very long time, so aa_put_buffer() never returns buffers to the global
list, which can starve other CPUs and force repeated kmalloc(aa_g_path_max)
allocations.

Guard the decrement so hold never underflows.
Fixes: ea9bae12d0 ("apparmor: cache buffers on percpu list if there is lock contention")

Signed-off-by: Zhengmian Hu <huzhengmian@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-26 14:59:42 -08:00
John Johansen
4610d536ff apparmor: make label_match return a consistent value
[ Upstream commit a4c9efa4db ]

compound match is inconsistent in returning a state or an integer error
this is problemati if the error is ever used as a state in the state
machine

Fixes: f1bd904175 ("apparmor: add the base fns() for domain labels")
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-26 14:59:42 -08:00
John Johansen
9ef2564577 apparmor: remove apply_modes_to_perms from label_match
[ Upstream commit b2e27be294 ]

The modes shouldn't be applied at the point of label match, it just
results in them being applied multiple times. Instead they should be
applied after which is already being done by all callers so it can
just be dropped from label_match.

Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Stable-dep-of: a4c9efa4db ("apparmor: make label_match return a consistent value")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-26 14:59:41 -08:00
John Johansen
9bf1fa1507 apparmor: fix rlimit for posix cpu timers
[ Upstream commit 6ca56813f4 ]

Posix cpu timers requires an additional step beyond setting the rlimit.
Refactor the code so its clear when what code is setting the
limit and conditionally update the posix cpu timers when appropriate.

Fixes: baa73d9e47 ("posix-timers: Make them configurable")
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-26 14:59:41 -08:00
John Johansen
b2a8011ae8 apparmor: move check for aa_null file to cover all cases
[ Upstream commit 4a134723f9 ]

files with a dentry pointing aa_null.dentry where already rejected as
part of file_inheritance. Unfortunately the check in
common_file_perm() is insufficient to cover all cases causing
unnecessary audit messages without the original files context.

Eg.
[ 442.886474] audit: type=1400 audit(1704822661.616:329): apparmor="DENIED" operation="file_inherit" class="file" namespace="root//lxd-juju-98527a-0_<var-snap-lxd-common-lxd>" profile="snap.lxd.activate" name="/apparmor/.null" pid=9525 comm="snap-exec"

Further examples of this are in the logs of
https://bugs.launchpad.net/ubuntu/+source/apparmor/+bug/2120439
https://bugs.launchpad.net/ubuntu/+source/snapd/+bug/1952084
https://bugs.launchpad.net/snapd/+bug/2049099

These messages have no value and should not be sent to the logs.
AppArmor was already filtering the out in some cases but the original
patch did not catch all cases. Fix this by push the existing check
down into two functions that should cover all cases.

Link: https://bugs.launchpad.net/ubuntu/+source/apparmor/+bug/2122743
Fixes: 192ca6b55a ("apparmor: revalidate files during exec")
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-26 14:59:41 -08:00
Ryan Lee
7757757908 apparmor: account for in_atomic removal in common_file_perm
[ Upstream commit 9b829c0aa9 ]

If we are not in an atomic context in common_file_perm, then we don't have
to use the atomic versions, resulting in improved performance outside of
atomic contexts.

Signed-off-by: Ryan Lee <ryan.lee@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Stable-dep-of: 4a134723f9 ("apparmor: move check for aa_null file to cover all cases")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-26 14:59:41 -08:00
John Johansen
f3cb5e58a6 apparmor: drop in_atomic flag in common_mmap, and common_file_perm
[ Upstream commit c3f27ccdb2 ]

with the previous changes to mmap the in_atomic flag is now always
false, so drop it.

Suggested-by: Tyler Hicks <code@tyhicks.com>
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Stable-dep-of: 4a134723f9 ("apparmor: move check for aa_null file to cover all cases")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-26 14:59:41 -08:00
Ryan Lee
1eadeb462e apparmor: fix boolean argument in apparmor_mmap_file
[ Upstream commit 48d5268e91 ]

The previous value of GFP_ATOMIC is an int and not a bool, potentially
resulting in UB when being assigned to a bool. In addition, the mmap hook
is called outside of locks (i.e. in a non-atomic context), so we can pass
a fixed constant value of false instead to common_mmap.

Signed-off-by: Ryan Lee <ryan.lee@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Stable-dep-of: 4a134723f9 ("apparmor: move check for aa_null file to cover all cases")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-26 14:59:41 -08:00
Ryan Lee
ac8f179e5c apparmor: return -ENOMEM in unpack_perms_table upon alloc failure
[ Upstream commit 74b7105e53 ]

In policy_unpack.c:unpack_perms_table, the perms struct is allocated via
kcalloc, with the position being reset if the allocation fails. However,
the error path results in -EPROTO being retured instead of -ENOMEM. Fix
this to return the correct error code.

Reported-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
Fixes: fd1b2b95a2 ("apparmor: add the ability for policy to specify a permission table")
Reviewed-by: Tyler Hicks <code@tyhicks.com>
Signed-off-by: Ryan Lee <ryan.lee@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-26 14:59:41 -08:00
Helge Deller
e027999049 apparmor: Fix & Optimize table creation from possibly unaligned memory
[ Upstream commit 6fc367bfd4 ]

Source blob may come from userspace and might be unaligned.
Try to optize the copying process by avoiding unaligned memory accesses.

- Added Fixes tag
- Added "Fix &" to description as this doesn't just optimize but fixes
        a potential unaligned memory access
Fixes: e6e8bf4188 ("apparmor: fix restricted endian type warnings for dfa unpack")
Signed-off-by: Helge Deller <deller@gmx.de>
[jj: remove duplicate word "convert" in comment trigger checkpatch warning]
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-26 14:59:41 -08:00
Helge Deller
23f112bd61 AppArmor: Allow apparmor to handle unaligned dfa tables
[ Upstream commit 64802f7312 ]

The dfa tables can originate from kernel or userspace and 8-byte alignment
isn't always guaranteed and as such may trigger unaligned memory accesses
on various architectures. Resulting in the following

[   73.901376] WARNING: CPU: 0 PID: 341 at security/apparmor/match.c:316 aa_dfa_unpack+0x6cc/0x720
[   74.015867] Modules linked in: binfmt_misc evdev flash sg drm drm_panel_orientation_quirks backlight i2c_core configfs nfnetlink autofs4 ext4 crc16 mbcache jbd2 hid_generic usbhid sr_mod hid cdrom
sd_mod ata_generic ohci_pci ehci_pci ehci_hcd ohci_hcd pata_ali libata sym53c8xx scsi_transport_spi tg3 scsi_mod usbcore libphy scsi_common mdio_bus usb_common
[   74.428977] CPU: 0 UID: 0 PID: 341 Comm: apparmor_parser Not tainted 6.18.0-rc6+ #9 NONE
[   74.536543] Call Trace:
[   74.568561] [<0000000000434c24>] dump_stack+0x8/0x18
[   74.633757] [<0000000000476438>] __warn+0xd8/0x100
[   74.696664] [<00000000004296d4>] warn_slowpath_fmt+0x34/0x74
[   74.771006] [<00000000008db28c>] aa_dfa_unpack+0x6cc/0x720
[   74.843062] [<00000000008e643c>] unpack_pdb+0xbc/0x7e0
[   74.910545] [<00000000008e7740>] unpack_profile+0xbe0/0x1300
[   74.984888] [<00000000008e82e0>] aa_unpack+0xe0/0x6a0
[   75.051226] [<00000000008e3ec4>] aa_replace_profiles+0x64/0x1160
[   75.130144] [<00000000008d4d90>] policy_update+0xf0/0x280
[   75.201057] [<00000000008d4fc8>] profile_replace+0xa8/0x100
[   75.274258] [<0000000000766bd0>] vfs_write+0x90/0x420
[   75.340594] [<00000000007670cc>] ksys_write+0x4c/0xe0
[   75.406932] [<0000000000767174>] sys_write+0x14/0x40
[   75.472126] [<0000000000406174>] linux_sparc_syscall+0x34/0x44
[   75.548802] ---[ end trace 0000000000000000 ]---
[   75.609503] dfa blob stream 0xfff0000008926b96 not aligned.
[   75.682695] Kernel unaligned access at TPC[8db2a8] aa_dfa_unpack+0x6e8/0x720

Work around it by using the get_unaligned_xx() helpers.

Fixes: e6e8bf4188 ("apparmor: fix restricted endian type warnings for dfa unpack")
Reported-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Closes: https://github.com/sparclinux/issues/issues/30
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-26 14:59:41 -08:00
John Johansen
ccb66a3c6c apparmor: fix NULL sock in aa_sock_file_perm
[ Upstream commit 00b6765753 ]

Deal with the potential that sock and sock-sk can be NULL during
socket setup or teardown. This could lead to an oops. The fix for NULL
pointer dereference in __unix_needs_revalidation shows this is at
least possible for af_unix sockets. While the fix for af_unix sockets
applies for newer mediation this is still the fall back path for older
af_unix mediation and other sockets, so ensure it is covered.

Fixes: 56974a6fcf ("apparmor: add base infastructure for socket mediation")
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-26 14:59:41 -08:00
System Administrator
fea017a7f6 apparmor: fix NULL pointer dereference in __unix_needs_revalidation
[ Upstream commit e2938ad00b ]

When receiving file descriptors via SCM_RIGHTS, both the socket pointer
and the socket's sk pointer can be NULL during socket setup or teardown,
causing NULL pointer dereferences in __unix_needs_revalidation().

This is a regression in AppArmor 5.0.0 (kernel 6.17+) where the new
__unix_needs_revalidation() function was added without proper NULL checks.

The crash manifests as:
  BUG: kernel NULL pointer dereference, address: 0x0000000000000018
  RIP: aa_file_perm+0xb7/0x3b0 (or +0xbe/0x3b0, +0xc0/0x3e0)
  Call Trace:
   apparmor_file_receive+0x42/0x80
   security_file_receive+0x2e/0x50
   receive_fd+0x1d/0xf0
   scm_detach_fds+0xad/0x1c0

The function dereferences sock->sk->sk_family without checking if either
sock or sock->sk is NULL first.

Add NULL checks for both sock and sock->sk before accessing sk_family.

Fixes: 88fec3526e ("apparmor: make sure unix socket labeling is correctly updated.")
Reported-by: Jamin Mc <jaminmc@gmail.com>
Closes: https://bugzilla.proxmox.com/show_bug.cgi?id=7083
Closes: https://gitlab.com/apparmor/apparmor/-/issues/568
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Signed-off-by: System Administrator <root@localhost>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-26 14:59:41 -08:00
Linus Torvalds
50647a1176 file->f_path constification
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQQqUNBr3gm4hGXdBJlZ7Krx/gZQ6wUCaN3daAAKCRBZ7Krx/gZQ
 6zNWAP9kD6rOJRNqDgea4pibDPa47Tps/WM5tsDv3dsLliY29gEA6sveOWZ3guAj
 4oY3ts/NtHLWXvhI7Vd/1mr2aTKEZQk=
 =YNK+
 -----END PGP SIGNATURE-----

Merge tag 'pull-f_path' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull file->f_path constification from Al Viro:
 "Only one thing was modifying ->f_path of an opened file - acct(2).

  Massaging that away and constifying a bunch of struct path * arguments
  in functions that might be given &file->f_path ends up with the
  situation where we can turn ->f_path into an anon union of const
  struct path f_path and struct path __f_path, the latter modified only
  in a few places in fs/{file_table,open,namei}.c, all for struct file
  instances that are yet to be opened"

* tag 'pull-f_path' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (23 commits)
  Have cc(1) catch attempts to modify ->f_path
  kernel/acct.c: saner struct file treatment
  configfs:get_target() - release path as soon as we grab configfs_item reference
  apparmor/af_unix: constify struct path * arguments
  ovl_is_real_file: constify realpath argument
  ovl_sync_file(): constify path argument
  ovl_lower_dir(): constify path argument
  ovl_get_verity_digest(): constify path argument
  ovl_validate_verity(): constify {meta,data}path arguments
  ovl_ensure_verity_loaded(): constify datapath argument
  ksmbd_vfs_set_init_posix_acl(): constify path argument
  ksmbd_vfs_inherit_posix_acl(): constify path argument
  ksmbd_vfs_kern_path_unlock(): constify path argument
  ksmbd_vfs_path_lookup_locked(): root_share_path can be const struct path *
  check_export(): constify path argument
  export_operations->open(): constify path argument
  rqst_exp_get_by_name(): constify path argument
  nfs: constify path argument of __vfs_getattr()
  bpf...d_path(): constify path argument
  done_path_create(): constify path argument
  ...
2025-10-03 16:32:36 -07:00
Linus Torvalds
56a0810d8c audit/stable-6.18 PR 20250926
-----BEGIN PGP SIGNATURE-----
 
 iQJIBAABCgAyFiEES0KozwfymdVUl37v6iDy2pc3iXMFAmjWq5oUHHBhdWxAcGF1
 bC1tb29yZS5jb20ACgkQ6iDy2pc3iXPTjRAAwYapnw+ZGdFtTGIDT63HtlKjCGHg
 DRR8J1RYWhxQL78dInjl7hlGPd4ULdpdF6zsh27X/8OsdFotw4NhDyPJwS1qWZv9
 uBJMy/s1Qi1V/rrtDygLGgkQ9ICfl/hgVh3L+g9AXU8H9IapMULp33z+2ueFU4rA
 PXgXppgNQTOhIQml0tagY7iPlLaaI1uPv/Dbvt792CSrKZReC+uiDSQKD6SUy5oJ
 NBRs0emdCqbllo8Eo7wTGdfzUttsPWYHe7X9BGCMK2bHp0BpMnFBDtuipUAgjNE8
 O16EkAtBMpEBW9VEFvDYW1jMFO7ccD8b09CbqPLdE7E0GeigTiODg+FdncKEpZn0
 Dl4xPbIoPBHVrDHKFK3HcuEdUs0FZH3NpTLFRg0/nWbg3CfSOFq1ZKhSbwLTZ48V
 2Iq22G0hIIl3yTEePSoR8xCSQkWf6hA1SVvzBqw5Xn1tnkdIUuM+KzeZUPKxCOiH
 r5b3ufrN5YMAcmc59q393sNuSMd7s97fohhK8/HouB93EcVNM2UjLEKVJnhMhYRE
 N21O17jwQG9F+OYTnmtMzuUF6yxwSAmkzQOg6F+lalJ8MECnNrZOEeyuA3d5ISi5
 4ZrXHWw90qaDy9lCV1o0UwWt9na+WxeMCJNpI07h5V1k3x7BULiI6WeP7J1qnY9r
 YlLv/6Hgx29dtqE=
 =iQal
 -----END PGP SIGNATURE-----

Merge tag 'audit-pr-20250926' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit

Pull audit updates from Paul Moore:

 - Proper audit support for multiple LSMs

   As the audit subsystem predated the work to enable multiple LSMs,
   some additional work was needed to support logging the different LSM
   labels for the subjects/tasks and objects on the system. Casey's
   patches add new auxillary records for subjects and objects that
   convey the additional labels.

 - Ensure fanotify audit events are always generated

   Generally speaking security relevant subsystems always generate audit
   events, unless explicitly ignored. However, up to this point fanotify
   events had been ignored by default, but starting with this pull
   request fanotify follows convention and generates audit events by
   default.

 - Replace an instance of strcpy() with strscpy()

 - Minor indentation, style, and comment fixes

* tag 'audit-pr-20250926' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
  audit: fix skb leak when audit rate limit is exceeded
  audit: init ab->skb_list earlier in audit_buffer_alloc()
  audit: add record for multiple object contexts
  audit: add record for multiple task security contexts
  lsm: security_lsmblob_to_secctx module selection
  audit: create audit_stamp structure
  audit: add a missing tab
  audit: record fanotify event regardless of presence of rules
  audit: fix typo in auditfilter.c comment
  audit: Replace deprecated strcpy() with strscpy()
  audit: fix indentation in audit_log_exit()
2025-09-30 08:22:16 -07:00
Al Viro
39e6bc58b8 apparmor/af_unix: constify struct path * arguments
unix_sk(sock)->path should never be modified, least of all by LSM...

Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-09-15 21:17:10 -04:00
Simon Schuster
edd3cb05c0 copy_process: pass clone_flags as u64 across calltree
With the introduction of clone3 in commit 7f192e3cd3 ("fork: add
clone3") the effective bit width of clone_flags on all architectures was
increased from 32-bit to 64-bit, with a new type of u64 for the flags.
However, for most consumers of clone_flags the interface was not
changed from the previous type of unsigned long.

While this works fine as long as none of the new 64-bit flag bits
(CLONE_CLEAR_SIGHAND and CLONE_INTO_CGROUP) are evaluated, this is still
undesirable in terms of the principle of least surprise.

Thus, this commit fixes all relevant interfaces of callees to
sys_clone3/copy_process (excluding the architecture-specific
copy_thread) to consistently pass clone_flags as u64, so that
no truncation to 32-bit integers occurs on 32-bit architectures.

Signed-off-by: Simon Schuster <schuster.simon@siemens-energy.com>
Link: https://lore.kernel.org/20250901-nios2-implement-clone3-v2-2-53fcf5577d57@siemens-energy.com
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-01 15:31:34 +02:00
Casey Schaufler
eb59d494ee audit: add record for multiple task security contexts
Replace the single skb pointer in an audit_buffer with a list of
skb pointers. Add the audit_stamp information to the audit_buffer as
there's no guarantee that there will be an audit_context containing
the stamp associated with the event. At audit_log_end() time create
auxiliary records as have been added to the list. Functions are
created to manage the skb list in the audit_buffer.

Create a new audit record AUDIT_MAC_TASK_CONTEXTS.
An example of the MAC_TASK_CONTEXTS record is:

    type=MAC_TASK_CONTEXTS
      msg=audit(1600880931.832:113)
      subj_apparmor=unconfined
      subj_smack=_

When an audit event includes a AUDIT_MAC_TASK_CONTEXTS record the
"subj=" field in other records in the event will be "subj=?".
An AUDIT_MAC_TASK_CONTEXTS record is supplied when the system has
multiple security modules that may make access decisions based on a
subject security context.

Refactor audit_log_task_context(), creating a new audit_log_subj_ctx().
This is used in netlabel auditing to provide multiple subject security
contexts as necessary.

Suggested-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
[PM: subj tweak, audit example readability indents]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-08-30 10:15:30 -04:00
Linus Torvalds
8b45c6c90a + Features
- improve debug printing
   - carry mediation check on label (optimization)
   - improve ability for compiler to optimize __begin_current_label_crit_section
   - transition for a linked list of rulesets to a vector of rulesets
   - don't hardcode profile signal, allow it to be set by policy
   - ability to mediate caps via the state machine instead of lut
   - Add Ubuntu af_unix mediation, put it behind new v9 abi
 
 + Cleanups
   - fix typos and spelling errors
   - cleanup kernel doc and code inconsistencies
   - remove redundant checks/code
   - remove unused variables
   - Use str_yes_no() helper function
   - mark tables static where appropriate
   - make all generated string array headers const char *const
   - refactor to doc semantics of file_perm checks
   - replace macro calls to network/socket fns with explicit calls
   - refactor/cleanup socket mediation code preparing for finer grained
     mediation of different network families
   - several updates to kernel doc comments
 
 + Bug fixes
   - apparmor: Fix incorrect profile->signal range check
   - idmap mount fixes
   - policy unpack unaligned access fixes
   - kfree_sensitive() where appropriate
   - fix oops when freeing policy
   - fix conflicting attachment resolution
   - fix exec table look-ups when stacking isn't first
   - fix exec auditing
   - mitigate userspace generating overly large xtables
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE7cSDD705q2rFEEf7BS82cBjVw9gFAmiQmakACgkQBS82cBjV
 w9jvKBAAn/HblSPo112ycW/yjeonkyiCY56LvyeU1YWQ8m370xPqM3yK2SHcj2i1
 we1mx5beDxbH5xn7c6w0EtyoHP7FNhyHp7neG8/WaJ1JG4uxv9HvrDmEJeQEJn/3
 5AP1q2dZF9NwnKBfB5zjwZXBJzncWtYBoLUjYMbehWlQjufT2yElyM8YZZN8ziLE
 M5ILVX6UMGpBH/zuX5kN2idLcubnv5MvLo2IEt+/nGLPbed44w+mZTM5WOTbzPNq
 w8axyNdhGt9kcSGwWuM+48T4oLfwagoxIZ3RXSQ4eExk6I8ZaFXua8nknC9wENN4
 9vkzDSWAupQ+o1bLKVNMVkqvBIIqmvEWvwket/hiyxs3Y5PDckRqOgQ/4Wbmgp9B
 KhLXxzIrF9PXkZ/rpMzloxnvDtMwoSScDShhW4TCRCmpDo/GwPwoPIpgbnc3kTq0
 poomca9KZ7YEnX/90Bh92Duo5OBDOHYlbWVE7EWX01htcxExQJt47JK48C25cY5p
 /cVDVepoz7EnKjB7mm9k6K1gYGvDeu3W1whRZNEK74AQJ7p+CrBoU+WjeMmZqP5V
 s47cLF17hbnw4ZvfsxQDkPgSOP1kuJIVlwFV2lPQk5hDcT6V0kZtqUzczKJSqeJb
 CGOkKvM7ao/7Cn8pmDNG1ZuPl/HuJ6wjlxt7SVt4/3rzLFzwglo=
 =Djjn
 -----END PGP SIGNATURE-----

Merge tag 'apparmor-pr-2025-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor

Pull apparmor updates from John Johansen:
 "This has one major feature, it pulls in a cleaned up version of
  af_unix mediation that Ubuntu has been carrying for years. It is
  placed behind a new abi to ensure that it does cause policy
  regressions. With pulling in the af_unix mediation there have been
  cleanups and some refactoring of network socket mediation. This
  accounts for the majority of the changes in the diff.

  In addition there are a few improvements providing minor code
  optimizations. several code cleanups, and bug fixes.

  Features:
   - improve debug printing
   - carry mediation check on label (optimization)
   - improve ability for compiler to optimize
     __begin_current_label_crit_section
   - transition for a linked list of rulesets to a vector of rulesets
   - don't hardcode profile signal, allow it to be set by policy
   - ability to mediate caps via the state machine instead of lut
   - Add Ubuntu af_unix mediation, put it behind new v9 abi

  Cleanups:
   - fix typos and spelling errors
   - cleanup kernel doc and code inconsistencies
   - remove redundant checks/code
   - remove unused variables
   - Use str_yes_no() helper function
   - mark tables static where appropriate
   - make all generated string array headers const char *const
   - refactor to doc semantics of file_perm checks
   - replace macro calls to network/socket fns with explicit calls
   - refactor/cleanup socket mediation code preparing for finer grained
     mediation of different network families
   - several updates to kernel doc comments

  Bug fixes:
   - fix incorrect profile->signal range check
   - idmap mount fixes
   - policy unpack unaligned access fixes
   - kfree_sensitive() where appropriate
   - fix oops when freeing policy
   - fix conflicting attachment resolution
   - fix exec table look-ups when stacking isn't first
   - fix exec auditing
   - mitigate userspace generating overly large xtables"

* tag 'apparmor-pr-2025-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor: (60 commits)
  apparmor: fix: oops when trying to free null ruleset
  apparmor: fix Regression on linux-next (next-20250721)
  apparmor: fix test error: WARNING in apparmor_unix_stream_connect
  apparmor: Remove the unused variable rules
  apparmor: fix: accept2 being specifie even when permission table is presnt
  apparmor: transition from a list of rules to a vector of rules
  apparmor: fix documentation mismatches in val_mask_to_str and socket functions
  apparmor: remove redundant perms.allow MAY_EXEC bitflag set
  apparmor: fix kernel doc warnings for kernel test robot
  apparmor: Fix unaligned memory accesses in KUnit test
  apparmor: Fix 8-byte alignment for initial dfa blob streams
  apparmor: shift uid when mediating af_unix in userns
  apparmor: shift ouid when mediating hard links in userns
  apparmor: make sure unix socket labeling is correctly updated.
  apparmor: fix regression in fs based unix sockets when using old abi
  apparmor: fix AA_DEBUG_LABEL()
  apparmor: fix af_unix auditing to include all address information
  apparmor: Remove use of the double lock
  apparmor: update kernel doc comments for xxx_label_crit_section
  apparmor: make __begin_current_label_crit_section() indicate whether put is needed
  ...
2025-08-04 08:17:28 -07:00
John Johansen
5f49c2d1f4 apparmor: fix: oops when trying to free null ruleset
profile allocation is wrongly setting the number of entries on the
rules vector before any ruleset is assigned. If profile allocation
fails between ruleset allocation and assigning the first ruleset,
free_ruleset() will be called with a null pointer resulting in an
oops.

[  107.350226] kernel BUG at mm/slub.c:545!
[  107.350912] Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[  107.351447] CPU: 1 UID: 0 PID: 27 Comm: ksoftirqd/1 Not tainted 6.14.6-hwe-rlee287-dev+ #5
[  107.353279] Hardware name:[   107.350218] -QE-----------[ cutMU here ]--------- Ub---
[  107.3502untu26] kernel BUG a 24t mm/slub.c:545.!04 P
[  107.350912]C ( Oops: invalid oi4pcode: 0000 [#1]40 PREEMPT SMP NOPFXTI
 + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[  107.356054] RIP: 0010:__slab_free+0x152/0x340
[  107.356444] Code: 00 4c 89 ff e8 0f ac df 00 48 8b 14 24 48 8b 4c 24 20 48 89 44 24 08 48 8b 03 48 c1 e8 09 83 e0 01 88 44 24 13 e9 71 ff ff ff <0f> 0b 41 f7 44 24 08 87 04 00 00 75 b2 eb a8 41 f7 44 24 08 87 04
[  107.357856] RSP: 0018:ffffad4a800fbbb0 EFLAGS: 00010246
[  107.358937] RAX: ffff97ebc2a88e70 RBX: ffffd759400aa200 RCX: 0000000000800074
[  107.359976] RDX: ffff97ebc2a88e60 RSI: ffffd759400aa200 RDI: ffffad4a800fbc20
[  107.360600] RBP: ffffad4a800fbc50 R08: 0000000000000001 R09: ffffffff86f02cf2
[  107.361254] R10: 0000000000000000 R11: 0000000000000000 R12: ffff97ecc0049400
[  107.361934] R13: ffff97ebc2a88e60 R14: ffff97ecc0049400 R15: 0000000000000000
[  107.362597] FS:  0000000000000000(0000) GS:ffff97ecfb200000(0000) knlGS:0000000000000000
[  107.363332] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  107.363784] CR2: 000061c9545ac000 CR3: 0000000047aa6000 CR4: 0000000000750ef0
[  107.364331] PKRU: 55555554
[  107.364545] Call Trace:
[  107.364761]  <TASK>
[  107.364931]  ? local_clock+0x15/0x30
[  107.365219]  ? srso_alias_return_thunk+0x5/0xfbef5
[  107.365593]  ? kfree_sensitive+0x32/0x70
[  107.365900]  kfree+0x29d/0x3a0
[  107.366144]  ? srso_alias_return_thunk+0x5/0xfbef5
[  107.366510]  ? local_clock_noinstr+0xe/0xd0
[  107.366841]  ? srso_alias_return_thunk+0x5/0xfbef5
[  107.367209]  kfree_sensitive+0x32/0x70
[  107.367502]  aa_free_profile.part.0+0xa2/0x400
[  107.367850]  ? rcu_do_batch+0x1e6/0x5e0
[  107.368148]  aa_free_profile+0x23/0x60
[  107.368438]  label_free_switch+0x4c/0x80
[  107.368751]  label_free_rcu+0x1c/0x50
[  107.369038]  rcu_do_batch+0x1e8/0x5e0
[  107.369324]  ? rcu_do_batch+0x157/0x5e0
[  107.369626]  rcu_core+0x1b0/0x2f0
[  107.369888]  rcu_core_si+0xe/0x20
[  107.370156]  handle_softirqs+0x9b/0x3d0
[  107.370460]  ? smpboot_thread_fn+0x26/0x210
[  107.370790]  run_ksoftirqd+0x3a/0x70
[  107.371070]  smpboot_thread_fn+0xf9/0x210
[  107.371383]  ? __pfx_smpboot_thread_fn+0x10/0x10
[  107.371746]  kthread+0x10d/0x280
[  107.372010]  ? __pfx_kthread+0x10/0x10
[  107.372310]  ret_from_fork+0x44/0x70
[  107.372655]  ? __pfx_kthread+0x10/0x10
[  107.372974]  ret_from_fork_asm+0x1a/0x30
[  107.373316]  </TASK>
[  107.373505] Modules linked in: af_packet_diag mptcp_diag tcp_diag udp_diag raw_diag inet_diag snd_seq_dummy snd_hrtimer snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device snd_timer snd soundcore qrtr binfmt_misc intel_rapl_msr intel_rapl_common kvm_amd ccp kvm irqbypass polyval_clmulni polyval_generic ghash_clmulni_intel sha256_ssse3 sha1_ssse3 aesni_intel crypto_simd cryptd i2c_piix4 i2c_smbus input_leds joydev sch_fq_codel msr parport_pc ppdev lp parport efi_pstore nfnetlink vsock_loopback vmw_vsock_virtio_transport_common vmw_vsock_vmci_transport vsock vmw_vmci dmi_sysfs qemu_fw_cfg ip_tables x_tables autofs4 hid_generic usbhid hid psmouse serio_raw floppy bochs pata_acpi
[  107.379086] ---[ end trace 0000000000000000 ]---

Don't set the count until a ruleset is actually allocated and
guard against free_ruleset() being called with a null pointer.

Reported-by: Ryan Lee <ryan.lee@canonical.com>
Fixes: 217af7e2f4 ("apparmor: refactor profile rules and attachments")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-08-04 01:14:56 -07:00
John Johansen
43584e9932 apparmor: fix Regression on linux-next (next-20250721)
sk lock initialization was incorrectly removed, from
apparmor_file_alloc_security() while testing changes to changes to
apparmor_sk_alloc_security()

resulting in the following regression.

[   48.056654] INFO: trying to register non-static key.
[   48.057480] The code is fine but needs lockdep annotation, or maybe
[   48.058416] you didn't initialize this object before use?
[   48.059209] turning off the locking correctness validator.
[   48.060040] CPU: 0 UID: 0 PID: 648 Comm: chronyd Not tainted 6.16.0-rc7-test-next-20250721-11410-g1ee809985e11-dirty #577 NONE
[   48.060049] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[   48.060055] Call Trace:
[   48.060059]  <TASK>
[   48.060063] dump_stack_lvl (lib/dump_stack.c:122)
[   48.060075] register_lock_class (kernel/locking/lockdep.c:988 kernel/locking/lockdep.c:1302)
[   48.060084] ? path_name (security/apparmor/file.c:159)
[   48.060093] __lock_acquire (kernel/locking/lockdep.c:5116)
[   48.060103] lock_acquire (kernel/locking/lockdep.c:473 (discriminator 4) kernel/locking/lockdep.c:5873 (discriminator 4) kernel/locking/lockdep.c:5828 (discriminator 4))
[   48.060109] ? update_file_ctx (security/apparmor/file.c:464)
[   48.060115] ? __pfx_profile_path_perm (security/apparmor/file.c:247)
[   48.060121] _raw_spin_lock (include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154)
[   48.060130] ? update_file_ctx (security/apparmor/file.c:464)
[   48.060134] update_file_ctx (security/apparmor/file.c:464)
[   48.060140] aa_file_perm (security/apparmor/file.c:532 (discriminator 1) security/apparmor/file.c:642 (discriminator 1))
[   48.060147] ? __pfx_aa_file_perm (security/apparmor/file.c:607)
[   48.060152] ? do_mmap (mm/mmap.c:558)
[   48.060160] ? __pfx_userfaultfd_unmap_complete (fs/userfaultfd.c:841)
[   48.060170] ? __lock_acquire (kernel/locking/lockdep.c:4677 (discriminator 1) kernel/locking/lockdep.c:5194 (discriminator 1))
[   48.060176] ? common_file_perm (security/apparmor/lsm.c:535 (discriminator 1))
[   48.060185] security_mmap_file (security/security.c:3012 (discriminator 2))
[   48.060192] vm_mmap_pgoff (mm/util.c:574 (discriminator 1))
[   48.060200] ? find_held_lock (kernel/locking/lockdep.c:5353 (discriminator 1))
[   48.060206] ? __pfx_vm_mmap_pgoff (mm/util.c:568)
[   48.060212] ? lock_release (kernel/locking/lockdep.c:5539 kernel/locking/lockdep.c:5892 kernel/locking/lockdep.c:5878)
[   48.060219] ? __fget_files (arch/x86/include/asm/preempt.h:85 (discriminator 13) include/linux/rcupdate.h:100 (discriminator 13) include/linux/rcupdate.h:873 (discriminator 13) fs/file.c:1072 (discriminator 13))
[   48.060229] ksys_mmap_pgoff (mm/mmap.c:604)
[   48.060239] do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1))
[   48.060248] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[   48.060254] RIP: 0033:0x7fb6920e30a2
[ 48.060265] Code: 08 00 04 00 00 eb e2 90 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 33 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5e 5b 5d c3 0f 1f 00 c7 05 e6 41 01 00 16 00
All code
========
   0:	08 00                	or     %al,(%rax)
   2:	04 00                	add    $0x0,%al
   4:	00 eb                	add    %ch,%bl
   6:	e2 90                	loop   0xffffffffffffff98
   8:	41 f7 c1 ff 0f 00 00 	test   $0xfff,%r9d
   f:	75 27                	jne    0x38
  11:	55                   	push   %rbp
  12:	89 cd                	mov    %ecx,%ebp
  14:	53                   	push   %rbx
  15:	48 89 fb             	mov    %rdi,%rbx
  18:	48 85 ff             	test   %rdi,%rdi
  1b:	74 33                	je     0x50
  1d:	41 89 ea             	mov    %ebp,%r10d
  20:	48 89 df             	mov    %rbx,%rdi
  23:	b8 09 00 00 00       	mov    $0x9,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 5e                	ja     0x90
  32:	5b                   	pop    %rbx
  33:	5d                   	pop    %rbp
  34:	c3                   	ret
  35:	0f 1f 00             	nopl   (%rax)
  38:	c7                   	.byte 0xc7
  39:	05 e6 41 01 00       	add    $0x141e6,%eax
  3e:	16                   	(bad)
	...

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 5e                	ja     0x66
   8:	5b                   	pop    %rbx
   9:	5d                   	pop    %rbp
   a:	c3                   	ret
   b:	0f 1f 00             	nopl   (%rax)
   e:	c7                   	.byte 0xc7
   f:	05 e6 41 01 00       	add    $0x141e6,%eax
  14:	16                   	(bad)
	...
[   48.060270] RSP: 002b:00007ffd2c0d3528 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
[   48.060279] RAX: ffffffffffffffda RBX: 00007fb691fc8000 RCX: 00007fb6920e30a2
[   48.060283] RDX: 0000000000000005 RSI: 000000000007d000 RDI: 00007fb691fc8000
[   48.060287] RBP: 0000000000000812 R08: 0000000000000003 R09: 0000000000011000
[   48.060290] R10: 0000000000000812 R11: 0000000000000206 R12: 00007ffd2c0d3578
[   48.060293] R13: 00007fb6920b6160 R14: 00007ffd2c0d39f0 R15: 00000fffa581a6a8

Fixes: 88fec3526e ("apparmor: make sure unix socket labeling is correctly updated.")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-30 05:01:38 -07:00
John Johansen
f3c0675bb9 apparmor: fix test error: WARNING in apparmor_unix_stream_connect
commit 88fec3526e ("apparmor: make sure unix socket labeling is correctly updated.")
added the use of security_sk_alloc() which ensures the sk label is
initialized.

This means that the AA_BUG in apparmor_unix_stream_connect() is no
longer correct, because while the sk is still not being initialized
by going through post_create, it is now initialize in sk_alloc().
Remove the now invalid check.

Reported-by: syzbot+cd38ee04bcb3866b0c6d@syzkaller.appspotmail.com
Fixes: 88fec3526e ("apparmor: make sure unix socket labeling is correctly updated.")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-30 05:00:47 -07:00
Jiapeng Chong
8936125e23 apparmor: Remove the unused variable rules
Variable rules is not effectively used, so delete it.

security/apparmor/lsm.c:182:23: warning: variable ‘rules’ set but not used.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=22942
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-30 04:57:56 -07:00
Linus Torvalds
4b65b859f5 Crypto library conversions for 6.17
Convert fsverity and apparmor to use the SHA-2 library functions
 instead of crypto_shash. This is simpler and also slightly faster.
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYIADIWIQSacvsUNc7UX4ntmEPzXCl4vpKOKwUCaIZ+MhQcZWJpZ2dlcnNA
 a2VybmVsLm9yZwAKCRDzXCl4vpKOK6LlAP42XrHo9hMqCnVs7uCtDVOk2kBUB7ml
 m7rkVqQLiEbgAAEAiFvQYPjiaUedTi+bH45+qP/O/LxY7y5laIby7QKa1wc=
 =X4Xs
 -----END PGP SIGNATURE-----

Merge tag 'libcrypto-conversions-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux

Pull crypto library conversions from Eric Biggers:
 "Convert fsverity and apparmor to use the SHA-2 library functions
  instead of crypto_shash. This is simpler and also slightly faster"

* tag 'libcrypto-conversions-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux:
  fsverity: Switch from crypto_shash to SHA-2 library
  fsverity: Explicitly include <linux/export.h>
  apparmor: use SHA-256 library API instead of crypto_shash API
2025-07-28 18:05:46 -07:00
John Johansen
4d9d1a08b7 apparmor: fix: accept2 being specifie even when permission table is presnt
The transition to the perms32 permission table dropped the need for
the accept2 table as permissions. However accept2 can be used for
flags and may be present even when the perms32 table is present. So
instead of checking on version, check whether the table is present.

Fixes: 2e12c5f060 ("apparmor: add additional flags to extended permission.")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-20 02:31:13 -07:00
John Johansen
9afdc6abb0 apparmor: transition from a list of rules to a vector of rules
The set of rules on a profile is not dynamically extended, instead
if a new ruleset is needed a new version of the profile is created.
This allows us to use a vector of rules instead of a list, slightly
reducing memory usage and simplifying the code.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-20 02:31:06 -07:00
Peng Jiang
f9c9dce01e apparmor: fix documentation mismatches in val_mask_to_str and socket functions
This patch fixes kernel-doc warnings:
1. val_mask_to_str:
- Added missing descriptions for `size` and `table` parameters.
- Removed outdated str_size and chrs references.
2. Socket Functions:
- Makes non-null requirements clear for socket/address args.
- Standardizes return values per kernel conventions.
- Adds Unix domain socket protocol details.

These changes silence doc validation warnings and improve accuracy for
AppArmor LSM docs.

Signed-off-by: Peng Jiang <jiang.peng9@zte.com.cn>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-20 02:19:28 -07:00
Ryan Lee
4ce7d3cf5a apparmor: remove redundant perms.allow MAY_EXEC bitflag set
This section of profile_transition that occurs after x_to_label only
happens if perms.allow already has the MAY_EXEC bit set, so we don't need
to set it again.

Fixes: 16916b17b4 ("apparmor: force auditing of conflicting attachment execs from confined")
Signed-off-by: Ryan Lee <ryan.lee@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-20 02:19:28 -07:00
John Johansen
da0edababa apparmor: fix kernel doc warnings for kernel test robot
Fix kernel doc warnings for the functions
- apparmor_socket_bind
- apparmor_unix_may_send
- apparmor_unix_stream_connect
- val_mask_to_str

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202506070127.B1bc3da4-lkp@intel.com/
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-20 02:19:27 -07:00
Helge Deller
c68804199d apparmor: Fix unaligned memory accesses in KUnit test
The testcase triggers some unnecessary unaligned memory accesses on the
parisc architecture:
  Kernel: unaligned access to 0x12f28e27 in policy_unpack_test_init+0x180/0x374 (iir 0x0cdc1280)
  Kernel: unaligned access to 0x12f28e67 in policy_unpack_test_init+0x270/0x374 (iir 0x64dc00ce)

Use the existing helper functions put_unaligned_le32() and
put_unaligned_le16() to avoid such warnings on architectures which
prefer aligned memory accesses.

Signed-off-by: Helge Deller <deller@gmx.de>
Fixes: 98c0cc48e2 ("apparmor: fix policy_unpack_test on big endian systems")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-20 02:19:27 -07:00
Helge Deller
c567de2c4f apparmor: Fix 8-byte alignment for initial dfa blob streams
The dfa blob stream for the aa_dfa_unpack() function is expected to be aligned
on a 8 byte boundary.

The static nulldfa_src[] and stacksplitdfa_src[] arrays store the initial
apparmor dfa blob streams, but since they are declared as an array-of-chars
the compiler and linker will only ensure a "char" (1-byte) alignment.

Add an __aligned(8) annotation to the arrays to tell the linker to always
align them on a 8-byte boundary. This avoids runtime warnings at startup on
alignment-sensitive platforms like parisc such as:

 Kernel: unaligned access to 0x7f2a584a in aa_dfa_unpack+0x124/0x788 (iir 0xca0109f)
 Kernel: unaligned access to 0x7f2a584e in aa_dfa_unpack+0x210/0x788 (iir 0xca8109c)
 Kernel: unaligned access to 0x7f2a586a in aa_dfa_unpack+0x278/0x788 (iir 0xcb01090)

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Fixes: 98b824ff89 ("apparmor: refcount the pdb")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-20 02:19:27 -07:00
Gabriel Totev
3fa0af4cc8 apparmor: shift uid when mediating af_unix in userns
Avoid unshifted ouids for socket file operations as observed when using
AppArmor profiles in unprivileged containers with LXD or Incus.

For example, root inside container and uid 1000000 outside, with
`owner /root/sock rw,` profile entry for nc:

/root$ nc -lkU sock & nc -U sock
==> dmesg
apparmor="DENIED" operation="connect" class="file"
namespace="root//lxd-podia_<var-snap-lxd-common-lxd>" profile="sockit"
name="/root/sock" pid=3924 comm="nc" requested_mask="wr" denied_mask="wr"
fsuid=1000000 ouid=0 [<== should be 1000000]

Fix by performing uid mapping as per common_perm_cond() in lsm.c

Signed-off-by: Gabriel Totev <gabriel.totev@zetier.com>
Fixes: c05e705812 ("apparmor: add fine grained af_unix mediation")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-20 02:19:27 -07:00
Gabriel Totev
c5bf96d20f apparmor: shift ouid when mediating hard links in userns
When using AppArmor profiles inside an unprivileged container,
the link operation observes an unshifted ouid.
(tested with LXD and Incus)

For example, root inside container and uid 1000000 outside, with
`owner /root/link l,` profile entry for ln:

/root$ touch chain && ln chain link
==> dmesg
apparmor="DENIED" operation="link" class="file"
namespace="root//lxd-feet_<var-snap-lxd-common-lxd>" profile="linkit"
name="/root/link" pid=1655 comm="ln" requested_mask="l" denied_mask="l"
fsuid=1000000 ouid=0 [<== should be 1000000] target="/root/chain"

Fix by mapping inode uid of old_dentry in aa_path_link() rather than
using it directly, similarly to how it's mapped in __file_path_perm()
later in the file.

Signed-off-by: Gabriel Totev <gabriel.totev@zetier.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-20 02:19:27 -07:00
John Johansen
88fec3526e apparmor: make sure unix socket labeling is correctly updated.
When a unix socket is passed into a different confinement domain make
sure its cached mediation labeling is updated to correctly reflect
which domains are using the socket.

Fixes: c05e705812 ("apparmor: add fine grained af_unix mediation")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-20 02:19:27 -07:00
John Johansen
6456ccbd2f apparmor: fix regression in fs based unix sockets when using old abi
Policy loaded using abi 7 socket mediation was not being applied
correctly in all cases. In some cases with fs based unix sockets a
subset of permissions where allowed when they should have been denied.

This was happening because the check for if the socket was an fs based
unix socket came before the abi check. But the abi check is where the
correct path is selected, so having the fs unix socket check occur
early would cause the wrong code path to be used.

Fix this by pushing the fs unix to be done after the abi check.

Fixes: dcd7a55941 ("apparmor: gate make fine grained unix mediation behind v9 abi")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-15 22:39:43 -07:00
John Johansen
50d56a1a36 apparmor: fix AA_DEBUG_LABEL()
AA_DEBUG_LABEL() was not specifying it vargs, which is needed so it can
output debug parameters.

Fixes: 71e6cff3e0 ("apparmor: Improve debug print infrastructure")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-15 22:39:43 -07:00
John Johansen
a30a9fdb66 apparmor: fix af_unix auditing to include all address information
The auditing of addresses currently doesn't include the source address
and mixes source and foreign/peer under the same audit name. Fix this
so source is always addr, and the foreign/peer is peer_addr.

Fixes: c05e705812 ("apparmor: add fine grained af_unix mediation")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-15 22:39:43 -07:00