locking/lockdep: Add kasan_check_byte() check in lock_acquire()

JIRA: https://issues.redhat.com/browse/RHEL-81997
Upstream Status: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git

commit de4b59d
Author: Waiman Long <longman@redhat.com>
Date:   Fri, 7 Mar 2025 15:26:56 -0800

    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

Signed-off-by: Waiman Long <longman@redhat.com>

Author: Waiman-Long

kernel/locking/lockdep.c

@@ -57,6 +57,7 @@
 #include <linux/lockdep.h>
 #include <linux/context_tracking.h>
 #include <linux/console.h>
+#include <linux/kasan.h>
 
 #include <asm/sections.h>
 
@@ -5738,6 +5739,14 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 	if (!debug_locks)
 		return;
 
+	/*
+	 * As KASAN instrumentation is disabled and lock_acquire() is usually
+	 * the first lockdep call when a task tries to acquire a lock, add
+	 * kasan_check_byte() here to check for use-after-free and other
+	 * memory errors.
+	 */
+	kasan_check_byte(lock);
+
 	if (unlikely(!lockdep_enabled())) {
 		/* XXX allow trylock from NMI ?!? */
 		if (lockdep_nmi() && !trylock) {