locking/lockdep: Add kasan_check_byte() check in lock_acquire()
authorWaiman Long <longman@redhat.com>
Fri, 7 Mar 2025 23:26:56 +0000 (15:26 -0800)
committerIngo Molnar <mingo@kernel.org>
Fri, 7 Mar 2025 23:55:04 +0000 (00:55 +0100)
commitde4b59d652646cf00cf632174348ca2266099edc
treef2bcbb57ea2a783a096a64011015005e6a17107f
parentee57ab5a32129f599ee1d358548dbebcb5e45953
locking/lockdep: Add kasan_check_byte() check in lock_acquire()

KASAN instrumentation of lockdep has been disabled, as we don't need
KASAN to check the validity of lockdep internal data structures and
incur unnecessary performance overhead. However, the lockdep_map pointer
passed in externally may not be valid (e.g. use-after-free) and we run
the risk of using garbage data resulting in false lockdep reports.

Add kasan_check_byte() call in lock_acquire() for non kernel core data
object to catch invalid lockdep_map and print out a KASAN report before
any lockdep splat, if any.

Suggested-by: Marco Elver <elver@google.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20250214195242.2480920-1-longman@redhat.com
Link: https://lore.kernel.org/r/20250307232717.1759087-7-boqun.feng@gmail.com
kernel/locking/lockdep.c