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| author | Maciek Borzecki <maciek.borzecki@gmail.com> | 2026-05-08 10:30:16 +0200 |
|---|---|---|
| committer | John Johansen <john.johansen@canonical.com> | 2026-06-13 20:20:13 -0700 |
| commit | bcd1b34c21748531a3febaf7440632b89d8deab7 (patch) | |
| tree | 704680334b487be67926b315d67dcc972251157b /security | |
| parent | add2b70038bea194bcdef8a680f9153ee7f93ac0 (diff) | |
| download | linux-bcd1b34c21748531a3febaf7440632b89d8deab7.tar.gz linux-bcd1b34c21748531a3febaf7440632b89d8deab7.tar.bz2 linux-bcd1b34c21748531a3febaf7440632b89d8deab7.zip | |
apparmor: fix uninitialised pointer passed to audit_log_untrustedstring()
Commit 4a134723f9f1 ("apparmor: move check for aa_null file to cover all cases")
intrdouced a small bug, where path_name() may pass a potentially uninitialized
*name to aa_audit_file() if the path->dentry had been replaced with
aa_null.dentry earlier on. This can lead to page fault like one observed on
7.0.2 openSUSE Tumbleweed kernel:
[51692.242756] [ T24690] BUG: unable to handle page fault for address: 0000000f00000003
[51692.242762] [ T24690] #PF: supervisor read access in kernel mode
[51692.242763] [ T24690] #PF: error_code(0x0000) - not-present page
[51692.242765] [ T24690] PGD 0 P4D 0
[51692.242768] [ T24690] Oops: Oops: 0000 [#1] SMP NOPTI
[51692.242772] [ T24690] CPU: 3 UID: 1020 PID: 24690 Comm: snap-confine Tainted: G O 7.0.2-1-default #1 PREEMPT(full) openSUSE Tumbleweed ab90b4c9940707f9cafa19bdad80b2cec52dbe51
[51692.242775] [ T24690] Tainted: [O]=OOT_MODULE
[51692.242777] [ T24690] Hardware name: Framework Laptop 13 (AMD Ryzen 7040Series)/FRANMDCP05, BIOS 03.18 01/08/2026
[51692.242778] [ T24690] RIP: 0010:strlen+0x4/0x30
[51692.242783] [ T24690] Code: f7 75 ec 31 c0 e9 17 9f 00 ff 48 89 f8 e9 0f 9f 00 ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <80> 3f 00 74 18 48 89 f8 0f 1f 40 00 48 83 c0 01 80 38 00 75 f7 48
[51692.242785] [ T24690] RSP: 0018:ffffd015eb1e3608 EFLAGS: 00010282
[51692.242787] [ T24690] RAX: 0000000000000000 RBX: ffff89796198a360 RCX: 0000000000000000
[51692.242788] [ T24690] RDX: 00000000000000d1 RSI: 0000000f00000003 RDI: 0000000f00000003
[51692.242790] [ T24690] RBP: ffffffffb7ede090 R08: 00000000000005f5 R09: 0000000000000000
[51692.242791] [ T24690] R10: 0000000000000000 R11: 0000000000000000 R12: ffffd015eb1e3700
[51692.242792] [ T24690] R13: ffff8977a22bc380 R14: ffffffffb7ec5190 R15: ffff8977a0c8aa80
[51692.242794] [ T24690] FS: 0000000000000000(0000) GS:ffff897f640d8000(0000) knlGS:0000000000000000
[51692.242796] [ T24690] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[51692.242797] [ T24690] CR2: 0000000f00000003 CR3: 00000006ad15f000 CR4: 0000000000f50ef0
[51692.242799] [ T24690] PKRU: 55555554
[51692.242800] [ T24690] Call Trace:
[51692.242802] [ T24690] <TASK>
[51692.242804] [ T24690] audit_log_untrustedstring+0x1d/0x40
[51692.242811] [ T24690] common_lsm_audit+0x71/0x1d0
[51692.242816] [ T24690] aa_audit+0x5a/0x170
[51692.242819] [ T24690] aa_audit_file+0x18a/0x1b0
[51692.242825] [ T24690] path_name+0xd2/0x100
[51692.242829] [ T24690] profile_path_perm.part.0+0x58/0xb0
[51692.242832] [ T24690] aa_path_perm+0xef/0x150
[51692.242837] [ T24690] apparmor_file_open+0x153/0x2e0
[51692.242840] [ T24690] security_file_open+0x46/0xd0
[51692.242844] [ T24690] do_dentry_open+0xe9/0x4d0
[51692.242848] [ T24690] vfs_open+0x30/0x100
While here, initialise variables which are passed down to path_name().
Fixes: 4a134723f9f1 ("apparmor: move check for aa_null file to cover all cases")
Signed-off-by: Maciek Borzecki <maciek.borzecki@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Diffstat (limited to 'security')
| -rw-r--r-- | security/apparmor/file.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/security/apparmor/file.c b/security/apparmor/file.c index fc5abd5473c8..c9d55fe1086f 100644 --- a/security/apparmor/file.c +++ b/security/apparmor/file.c @@ -158,9 +158,9 @@ static int path_name(const char *op, const struct cred *subj_cred, /* don't reaudit files closed during inheritance */ if (unlikely(path->dentry == aa_null.dentry)) return -EACCES; - else - error = aa_path_name(path, flags, buffer, name, &info, - labels_profile(label)->disconnected); + + error = aa_path_name(path, flags, buffer, name, &info, + labels_profile(label)->disconnected); if (error) { fn_for_each_confined(label, profile, aa_audit_file(subj_cred, @@ -250,7 +250,7 @@ static int profile_path_perm(const char *op, const struct cred *subj_cred, struct path_cond *cond, int flags, struct aa_perms *perms) { - const char *name; + const char *name = NULL; int error; if (profile_unconfined(profile)) @@ -328,7 +328,7 @@ static int profile_path_link(const struct cred *subj_cred, struct path_cond *cond) { struct aa_ruleset *rules = profile->label.rules[0]; - const char *lname, *tname = NULL; + const char *lname = NULL, *tname = NULL; struct aa_perms lperms = {}, perms; const char *info = NULL; u32 request = AA_MAY_LINK; |