On 11/27/23 09:59, Fedor Pchelkin wrote:
policy_db objects are allocated with kzalloc() inside aa_alloc_pdb() and are not cleared in the corresponding aa_free_pdb() function causing leak:unreferenced object 0xffff88801f0a1400 (size 192): comm "apparmor_parser", pid 1247, jiffies 4295122827 (age 2306.399s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff81ddc612>] __kmem_cache_alloc_node+0x1e2/0x2d0 [<ffffffff81c47c55>] kmalloc_trace+0x25/0xc0 [<ffffffff83eb9a12>] aa_alloc_pdb+0x82/0x140 [<ffffffff83ec4077>] unpack_pdb+0xc7/0x2700 [<ffffffff83ec6b10>] unpack_profile+0x450/0x4960 [<ffffffff83ecc129>] aa_unpack+0x309/0x15e0 [<ffffffff83ebdb23>] aa_replace_profiles+0x213/0x33c0 [<ffffffff83e8d341>] policy_update+0x261/0x370 [<ffffffff83e8d66e>] profile_replace+0x20e/0x2a0 [<ffffffff81eadfaf>] vfs_write+0x2af/0xe00 [<ffffffff81eaf4c6>] ksys_write+0x126/0x250 [<ffffffff890fa0b6>] do_syscall_64+0x46/0xf0 [<ffffffff892000ea>] entry_SYSCALL_64_after_hwframe+0x6e/0x76 Free the pdbs inside aa_free_pdb(). While at it, rename the variable representing an aa_policydb object to make the function more unified with aa_pdb_free_kref() and aa_alloc_pdb(). Found by Linux Verification Center (linuxtesting.org). Fixes: 98b824ff8984 ("apparmor: refcount the pdb") Signed-off-by: Fedor Pchelkin <pchel...@ispras.ru>
ouch, lgtm, I am going to pull this into my tree and throw some testing on this asap Acked-by: John Johansen <john.johan...@canonical.com>
--- security/apparmor/policy.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/security/apparmor/policy.c b/security/apparmor/policy.c index ed4c9803c8fa..957654d253dd 100644 --- a/security/apparmor/policy.c +++ b/security/apparmor/policy.c @@ -99,13 +99,14 @@ const char *const aa_profile_mode_names[] = { };-static void aa_free_pdb(struct aa_policydb *policy)+static void aa_free_pdb(struct aa_policydb *pdb) { - if (policy) { - aa_put_dfa(policy->dfa); - if (policy->perms) - kvfree(policy->perms); - aa_free_str_table(&policy->trans); + if (pdb) { + aa_put_dfa(pdb->dfa); + if (pdb->perms) + kvfree(pdb->perms); + aa_free_str_table(&pdb->trans); + kfree(pdb); } }
