Files
linux-nf/security
Massimiliano Pellizzer 9063d7e261 apparmor: validate DFA start states are in bounds in unpack_pdb
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>
2026-03-09 16:05:42 -07:00
..
2025-09-22 15:52:44 -04:00
2025-04-11 18:58:10 -07:00