On 9/10/21 1:29 AM, Bixuan Cui wrote: > 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. A fix for this was already merged: https://git.kernel.dk/cgit/linux-block/commit/?h=io_uring-5.15&id=66e70be722886e4f134350212baa13f217e39e42 -- Jens Axboe
