kernel/linux.git/security/apparmor/include, branch v6.6.75

ima: Avoid blocking in RCU read-side critical section

2024-07-11T10:49:18+00:00

commit 9a95c5bfbf02a0a7f5983280fe284a0ff0836c34 upstream. A panic happens in ima_match_policy: BUG: unable to handle kernel NULL pointer dereference at 0000000000000010 PGD 42f873067 P4D 0 Oops: 0000 [#1] SMP NOPTI CPU: 5 PID: 1286325 Comm: kubeletmonit.sh Kdump: loaded Tainted: P Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 RIP: 0010:ima_match_policy+0x84/0x450 Code: 49 89 fc 41 89 cf 31 ed 89 44 24 14 eb 1c 44 39 7b 18 74 26 41 83 ff 05 74 20 48 8b 1b 48 3b 1d f2 b9 f4 00 0f 84 9c 01 00 00 <44> 85 73 10 74 ea 44 8b 6b 14 41 f6 c5 01 75 d4 41 f6 c5 02 74 0f RSP: 0018:ff71570009e07a80 EFLAGS: 00010207 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000200 RDX: ffffffffad8dc7c0 RSI: 0000000024924925 RDI: ff3e27850dea2000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffffabfce739 R10: ff3e27810cc42400 R11: 0000000000000000 R12: ff3e2781825ef970 R13: 00000000ff3e2785 R14: 000000000000000c R15: 0000000000000001 FS: 00007f5195b51740(0000) GS:ff3e278b12d40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000010 CR3: 0000000626d24002 CR4: 0000000000361ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ima_get_action+0x22/0x30 process_measurement+0xb0/0x830 ? page_add_file_rmap+0x15/0x170 ? alloc_set_pte+0x269/0x4c0 ? prep_new_page+0x81/0x140 ? simple_xattr_get+0x75/0xa0 ? selinux_file_open+0x9d/0xf0 ima_file_check+0x64/0x90 path_openat+0x571/0x1720 do_filp_open+0x9b/0x110 ? page_counter_try_charge+0x57/0xc0 ? files_cgroup_alloc_fd+0x38/0x60 ? __alloc_fd+0xd4/0x250 ? do_sys_open+0x1bd/0x250 do_sys_open+0x1bd/0x250 do_syscall_64+0x5d/0x1d0 entry_SYSCALL_64_after_hwframe+0x65/0xca Commit c7423dbdbc9e ("ima: Handle -ESTALE returned by ima_filter_rule_match()") introduced call to ima_lsm_copy_rule within a RCU read-side critical section which contains kmalloc with GFP_KERNEL. This implies a possible sleep and violates limitations of RCU read-side critical sections on non-PREEMPT systems. Sleeping within RCU read-side critical section might cause synchronize_rcu() returning early and break RCU protection, allowing a UAF to happen. The root cause of this issue could be described as follows: | Thread A | Thread B | | |ima_match_policy | | | rcu_read_lock | |ima_lsm_update_rule | | | synchronize_rcu | | | | kmalloc(GFP_KERNEL)| | | sleep | ==> synchronize_rcu returns early | kfree(entry) | | | | entry = entry->next| ==> UAF happens and entry now becomes NULL (or could be anything). | | entry->action | ==> Accessing entry might cause panic. To fix this issue, we are converting all kmalloc that is called within RCU read-side critical section to use GFP_ATOMIC. Fixes: c7423dbdbc9e ("ima: Handle -ESTALE returned by ima_filter_rule_match()") Cc: stable@vger.kernel.org Signed-off-by: GUO Zihua Acked-by: John Johansen Reviewed-by: Mimi Zohar Reviewed-by: Casey Schaufler [PM: fixed missing comment, long lines, !CONFIG_IMA_LSM_RULES case] Signed-off-by: Paul Moore Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

apparmor: Fix regression in mount mediation

2023-11-28T17:20:07+00:00

[ Upstream commit 157a3537d6bc28ceb9a11fc8cb67f2152d860146 ] commit 2db154b3ea8e ("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 AppArmor mediation of mount. This patch provides a base mapping of the move_mount syscall to the existing mount mediation. In the future we may introduce additional mediations around the new mount calls. Fixes: 2db154b3ea8e ("vfs: syscall: Add move_mount(2) to move mounts around") CC: stable@vger.kernel.org Reported-by: Andreas Steinmetz Signed-off-by: John Johansen Signed-off-by: Sasha Levin

apparmor: pass cred through to audit info.

2023-11-28T17:20:07+00:00

[ Upstream commit 90c436a64a6e20482a9a613c47eb4af2e8a5328e ] The cred is needed to properly audit some messages, and will be needed in the future for uid conditional mediation. So pass it through to where the apparmor_audit_data struct gets defined. Reviewed-by: Georgia Garcia Signed-off-by: John Johansen Stable-dep-of: 157a3537d6bc ("apparmor: Fix regression in mount mediation") Signed-off-by: Sasha Levin

apparmor: rename audit_data->label to audit_data->subj_label

2023-11-28T17:20:07+00:00

[ Upstream commit d20f5a1a6e792d22199c9989ec7ab9e95c48d60c ] rename audit_data's label field to subj_label to better reflect its use. Also at the same time drop unneeded assignments to ->subj_label as the later call to aa_check_perms will do the assignment if needed. Reviewed-by: Georgia Garcia Signed-off-by: John Johansen Stable-dep-of: 157a3537d6bc ("apparmor: Fix regression in mount mediation") Signed-off-by: Sasha Levin

apparmor: combine common_audit_data and apparmor_audit_data

2023-11-28T17:20:07+00:00

[ Upstream commit bd7bd201ca46c211c3ab251ca9854787d1331a2f ] Everywhere where common_audit_data is used apparmor audit_data is also used. We can simplify the code and drop the use of the aad macro everywhere by combining the two structures. Reviewed-by: Georgia Garcia Signed-off-by: John Johansen Stable-dep-of: 157a3537d6bc ("apparmor: Fix regression in mount mediation") Signed-off-by: Sasha Levin

apparmor: Free up __cleanup() name

2023-06-26T09:14:18+00:00

In order to use __cleanup for __attribute__((__cleanup__(func))) the name must not be used for anything else. Avoid the conflict. Signed-off-by: Peter Zijlstra (Intel) Acked-by: John Johansen Link: https://lkml.kernel.org/r/20230612093537.536441207%40infradead.org

Merge tag 'apparmor-pr-2022-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor

2022-12-14T21:42:09+00:00

Pull apparmor updates from John Johansen: "Features: - switch to zstd compression for profile raw data Cleanups: - simplify obtaining the newest label on a cred - remove useless static inline functions - compute permission conversion on policy unpack - refactor code to share common permissins - refactor unpack to group policy backwards compatiblity code - add __init annotation to aa_{setup/teardown}_dfa_engine() Bug Fixes: - fix a memleak in - multi_transaction_new() - free_ruleset() - unpack_profile() - alloc_ns() - fix lockdep warning when removing a namespace - fix regression in stacking due to label flags - fix loading of child before parent - fix kernel-doc comments that differ from fns - fix spelling errors in comments - store return value of unpack_perms_table() to signed variable" * tag 'apparmor-pr-2022-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor: (64 commits) apparmor: Fix uninitialized symbol 'array_size' in policy_unpack_test.c apparmor: Add __init annotation to aa_{setup/teardown}_dfa_engine() apparmor: Fix memleak in alloc_ns() apparmor: Fix memleak issue in unpack_profile() apparmor: fix a memleak in free_ruleset() apparmor: Fix spelling of function name in comment block apparmor: Use pointer to struct aa_label for lbs_cred AppArmor: Fix kernel-doc LSM: Fix kernel-doc AppArmor: Fix kernel-doc apparmor: Fix loading of child before parent apparmor: refactor code that alloc null profiles apparmor: fix obsoleted comments for aa_getprocattr() and audit_resource() apparmor: remove useless static inline functions apparmor: Fix unpack_profile() warn: passing zero to 'ERR_PTR' apparmor: fix uninitialize table variable in error in unpack_trans_table apparmor: store return value of unpack_perms_table() to signed variable apparmor: Fix kunit test for out of bounds array apparmor: Fix decompression of rawdata for read back to userspace apparmor: Fix undefined references to zstd_ symbols ...

apparmor: test: make static symbols visible during kunit testing

2022-12-12T21:13:48+00:00

Use macros, VISIBLE_IF_KUNIT and EXPORT_SYMBOL_IF_KUNIT, to allow static symbols to be conditionally set to be visible during apparmor_policy_unpack_test, which removes the need to include the testing file in the implementation file. Change the namespace of the symbols that are now conditionally visible (by adding the prefix aa_) to avoid confusion with symbols of the same name. Allow the test to be built as a module and namespace the module name from policy_unpack_test to apparmor_policy_unpack_test to improve clarity of the module name. Provide an example of how static symbols can be dealt with in testing. Signed-off-by: Rae Moar Reviewed-by: David Gow Acked-by: John Johansen Signed-off-by: Shuah Khan

apparmor: refactor code that alloc null profiles

2022-10-25T05:35:36+00:00

Bother unconfined and learning profiles use the null profile as their base. Refactor so they are share a common base routine. This doesn't save much atm but will be important when the feature set of the parent is inherited. Signed-off-by: John Johansen

apparmor: Fix undefined references to zstd_ symbols

2022-10-03T21:49:04+00:00

Unfortunately the switch to using zstd compression did not properly ifdef all the code that uses zstd_ symbols. So that if exporting of binary policy is disabled in the config the compile will fail with the following errors security/apparmor/lsm.c:1545: undefined reference to `zstd_min_clevel' aarch64-linux-ld: security/apparmor/lsm.c:1545: undefined reference to `zstd_max_clevel' Reported-by: kernel test robot Fixes: 52ccc20c652b ("apparmor: use zstd compression for profile data") Signed-off-by: John Johansen Acked-by: Jon Tourville