Kmemleak tool detected a memory leak.
====================
unreferenced object 0xffff888126fcd6c0 (size 192):
comm "syz-executor.1", pid 11934, jiffies 4294983026 (age 15.690s)
hex dump (first 32 bytes):
01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff81632c91>] kmalloc_node include/linux/slab.h:609 [inline]
[<ffffffff81632c91>] kzalloc_node include/linux/slab.h:732 [inline]
[<ffffffff81632c91>] create_io_worker+0x41/0x1e0 fs/io-wq.c:739
[<ffffffff8163311e>] io_wqe_create_worker fs/io-wq.c:267 [inline]
[<ffffffff8163311e>] io_wqe_enqueue+0x1fe/0x330 fs/io-wq.c:866
[<ffffffff81620b64>] io_queue_async_work+0xc4/0x200 fs/io_uring.c:1473
[<ffffffff8162c59c>] __io_queue_sqe+0x34c/0x510 fs/io_uring.c:6933
[<ffffffff8162c7ab>] io_req_task_submit+0x4b/0xa0 fs/io_uring.c:2233
[<ffffffff8162cb48>] io_async_task_func+0x108/0x1c0 fs/io_uring.c:5462
[<ffffffff816259e3>] tctx_task_work+0x1b3/0x3a0 fs/io_uring.c:2158
[<ffffffff81269b43>] task_work_run+0x73/0xb0 kernel/task_work.c:164
[<ffffffff812dcdd1>] tracehook_notify_signal include/linux/tracehook.h:212 [inline]
[<ffffffff812dcdd1>] handle_signal_work kernel/entry/common.c:146 [inline]
[<ffffffff812dcdd1>] exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
[<ffffffff812dcdd1>] exit_to_user_mode_prepare+0x151/0x180 kernel/entry/common.c:209
[<ffffffff843ff25d>] __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
[<ffffffff843ff25d>] syscall_exit_to_user_mode+0x1d/0x40 kernel/entry/common.c:302
[<ffffffff843fa4a2>] do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
[<ffffffff84600068>] entry_SYSCALL_64_after_hwframe+0x44/0xae
====================
If io_should_retry_thread is false in create_io_worker() and
io_queue_worker_create is false in io_workqueue_create(), free the worker.
Fixes: 3146cba99aa2 ("io-wq: make worker creation resilient against signals")
Reported-by: syzbot+65454c239241d3d647da@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Bixuan Cui <cuibixuan@xxxxxxxxxx>
---
Changes in v2:
* Add free worker if io_queue_worker_create is false in io_workqueue_create();
* Add kmemleak calltrace in commit message;
fs/io-wq.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/fs/io-wq.c b/fs/io-wq.c
index d80e4a735677..c24f79cf2b97 100644
--- a/fs/io-wq.c
+++ b/fs/io-wq.c
@@ -725,6 +725,7 @@ static void io_workqueue_create(struct work_struct *work)
if (!io_queue_worker_create(worker, acct, create_worker_cont)) {
clear_bit_unlock(0, &worker->create_state);
io_worker_release(worker);
+ kfree(worker);
}
}
@@ -759,6 +760,7 @@ static bool create_io_worker(struct io_wq *wq, struct io_wqe *wqe, int index)
if (!IS_ERR(tsk)) {
io_init_new_worker(wqe, worker, tsk);
} else if (!io_should_retry_thread(PTR_ERR(tsk))) {
+ kfree(worker);
goto fail;
} else {
INIT_WORK(&worker->work, io_workqueue_create);
--
2.17.1
