linux-kernel - [PATCH v3] lockdep: Let lock_is_held_type() detect recursive read as read

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: <20210910135312.4axzdxt74rgct2ur@linutronix.de>
Date:   Fri, 10 Sep 2021 15:53:12 +0200
From:   Sebastian Andrzej Siewior <bigeasy@...utronix.de>
To:     Peter Zijlstra <peterz@...radead.org>
Cc:     Boqun Feng <boqun.feng@...il.com>, Waiman Long <llong@...hat.com>,
        linux-kernel@...r.kernel.org, Ingo Molnar <mingo@...hat.com>,
        Will Deacon <will@...nel.org>,
        Thomas Gleixner <tglx@...utronix.de>
Subject: [PATCH v3] lockdep: Let lock_is_held_type() detect recursive read as
 read

lock_is_held_type(, 1) detects acquired read locks. It only recognized
locks acquired with lock_acquire_shared(). Read locks acquired with
lock_acquire_shared_recursive() are not recognized because a `2' is
stored as the read value.

Rework the check to additionally recognise lock's read value one and two
as a read held lock.

Fixes: e918188611f07 ("locking: More accurate annotations for read_lock()")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@...utronix.de>
Acked-by: Waiman Long <longman@...hat.com>
Acked-by: Boqun Feng <boqun.feng@...il.com>
---
v3: move the !! to the right spot so it actually works.

 kernel/locking/lockdep.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index bf1c00c881e48..bfa0a347f27c4 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -5366,7 +5366,7 @@ int __lock_is_held(const struct lockdep_map *lock, int read)
 		struct held_lock *hlock = curr->held_locks + i;
 
 		if (match_held_lock(hlock, lock)) {
-			if (read == -1 || hlock->read == read)
+			if (read == -1 || !!hlock->read == read)
 				return LOCK_STATE_HELD;
 
 			return LOCK_STATE_NOT_HELD;
-- 
2.33.0