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authorSergey Senozhatsky <senozhatsky@chromium.org>2024-08-15 16:02:58 +0900
committerTejun Heo <tj@kernel.org>2024-08-21 06:13:26 -1000
commit84c425bef3409d69ddb171c89664f66030bbf9d9 (patch)
tree0d6698b8482e4aaeda53f6fc133f3a7b14a537af
parent9b59a85a84dc37ca4f2c54df5e06aff4c1eae5d3 (diff)
workqueue: fix null-ptr-deref on __alloc_workqueue() error
wq->lockdep_map is set only after __alloc_workqueue() successfully returns. However, on its error path __alloc_workqueue() may call destroy_workqueue() which expects wq->lockdep_map to be already set, which results in a null-ptr-deref in touch_wq_lockdep_map(). Add a simple NULL-check to touch_wq_lockdep_map(). Oops: general protection fault, probably for non-canonical address KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:__lock_acquire+0x81/0x7800 [..] Call Trace: <TASK> ? __die_body+0x66/0xb0 ? die_addr+0xb2/0xe0 ? exc_general_protection+0x300/0x470 ? asm_exc_general_protection+0x22/0x30 ? __lock_acquire+0x81/0x7800 ? mark_lock+0x94/0x330 ? __lock_acquire+0x12fd/0x7800 ? __lock_acquire+0x3439/0x7800 lock_acquire+0x14c/0x3e0 ? __flush_workqueue+0x167/0x13a0 ? __init_swait_queue_head+0xaf/0x150 ? __flush_workqueue+0x167/0x13a0 __flush_workqueue+0x17d/0x13a0 ? __flush_workqueue+0x167/0x13a0 ? lock_release+0x50f/0x830 ? drain_workqueue+0x94/0x300 drain_workqueue+0xe3/0x300 destroy_workqueue+0xac/0xc40 ? workqueue_sysfs_register+0x159/0x2f0 __alloc_workqueue+0x1506/0x1760 alloc_workqueue+0x61/0x150 ... Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Tejun Heo <tj@kernel.org>
-rw-r--r--kernel/workqueue.c3
1 files changed, 3 insertions, 0 deletions
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 7cc77adb18bb..03dc2c95d62e 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -3871,6 +3871,9 @@ static bool flush_workqueue_prep_pwqs(struct workqueue_struct *wq,
static void touch_wq_lockdep_map(struct workqueue_struct *wq)
{
#ifdef CONFIG_LOCKDEP
+ if (unlikely(!wq->lockdep_map))
+ return;
+
if (wq->flags & WQ_BH)
local_bh_disable();