linux-kernel - [tip: locking/core] locking/lockdep: Add kasan_check_byte() check in lock

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <174139248454.14745.10281410147550782244.tip-bot2@tip-bot2>
Date: Sat, 08 Mar 2025 00:08:04 -0000
From: "tip-bot2 for Waiman Long" <tip-bot2@...utronix.de>
To: linux-tip-commits@...r.kernel.org
Cc: Marco Elver <elver@...gle.com>, Waiman Long <longman@...hat.com>,
 Boqun Feng <boqun.feng@...il.com>, Ingo Molnar <mingo@...nel.org>,
 Andrey Konovalov <andreyknvl@...il.com>, x86@...nel.org,
 linux-kernel@...r.kernel.org
Subject: [tip: locking/core] locking/lockdep: Add kasan_check_byte() check in
 lock_acquire()

The following commit has been merged into the locking/core branch of tip:

Commit-ID:     de4b59d652646cf00cf632174348ca2266099edc
Gitweb:        https://git.kernel.org/tip/de4b59d652646cf00cf632174348ca2266099edc
Author:        Waiman Long <longman@...hat.com>
AuthorDate:    Fri, 07 Mar 2025 15:26:56 -08:00
Committer:     Ingo Molnar <mingo@...nel.org>
CommitterDate: Sat, 08 Mar 2025 00:55:04 +01:00

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@...gle.com>
Signed-off-by: Waiman Long <longman@...hat.com>
Signed-off-by: Boqun Feng <boqun.feng@...il.com>
Signed-off-by: Ingo Molnar <mingo@...nel.org>
Reviewed-by: Marco Elver <elver@...gle.com>
Reviewed-by: Andrey Konovalov <andreyknvl@...il.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 |  9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 8436f01..b15757e 100644
--- a/kernel/locking/lockdep.c
+++ b/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>
 
@@ -5830,6 +5831,14 @@ 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) {