Hello, syzbot found the following issue on: HEAD commit: f4d51dff Linux 5.9-rc4 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=13686dcd900000 kernel config: https://syzkaller.appspot.com/x/.config?x=8f5c353182ed6199 dashboard link: https://syzkaller.appspot.com/bug?extid=45fa0a195b941764e0f0 compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1378ceed900000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+45fa0a195b941764e0f0@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: use-after-free in instrument_atomic_write include/linux/instrumented.h:71 [inline] BUG: KASAN: use-after-free in atomic_inc include/asm-generic/atomic-instrumented.h:240 [inline] BUG: KASAN: use-after-free in io_wqe_inc_running fs/io-wq.c:301 [inline] BUG: KASAN: use-after-free in io_wq_worker_running+0xb4/0x100 fs/io-wq.c:613 Write of size 4 at addr ffff88821aaa388c by task io_wqe_worker-0/8276 CPU: 0 PID: 8276 Comm: io_wqe_worker-0 Not tainted 5.9.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d6/0x29e lib/dump_stack.c:118 print_address_description+0x66/0x620 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report+0x132/0x1d0 mm/kasan/report.c:530 check_memory_region_inline mm/kasan/generic.c:183 [inline] check_memory_region+0x2b5/0x2f0 mm/kasan/generic.c:192 instrument_atomic_write include/linux/instrumented.h:71 [inline] atomic_inc include/asm-generic/atomic-instrumented.h:240 [inline] io_wqe_inc_running fs/io-wq.c:301 [inline] io_wq_worker_running+0xb4/0x100 fs/io-wq.c:613 schedule_timeout+0x15c/0x250 kernel/time/timer.c:1879 io_wqe_worker+0x60b/0x810 fs/io-wq.c:580 kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Allocated by task 8273: kasan_save_stack mm/kasan/common.c:48 [inline] kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc+0x100/0x130 mm/kasan/common.c:461 kmem_cache_alloc_node_trace+0x1f7/0x2a0 mm/slab.c:3594 kmalloc_node include/linux/slab.h:572 [inline] kzalloc_node include/linux/slab.h:677 [inline] io_wq_create+0x295/0x880 fs/io-wq.c:1064 io_init_wq_offload fs/io_uring.c:7432 [inline] io_sq_offload_start fs/io_uring.c:7504 [inline] io_uring_create fs/io_uring.c:8625 [inline] io_uring_setup fs/io_uring.c:8694 [inline] __do_sys_io_uring_setup fs/io_uring.c:8700 [inline] __se_sys_io_uring_setup+0x18ed/0x2a00 fs/io_uring.c:8697 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 8175: kasan_save_stack mm/kasan/common.c:48 [inline] kasan_set_track+0x3d/0x70 mm/kasan/common.c:56 kasan_set_free_info+0x17/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0xdd/0x110 mm/kasan/common.c:422 __cache_free mm/slab.c:3418 [inline] kfree+0x113/0x200 mm/slab.c:3756 __io_wq_destroy fs/io-wq.c:1138 [inline] io_wq_destroy+0x470/0x510 fs/io-wq.c:1146 io_finish_async fs/io_uring.c:6836 [inline] io_ring_ctx_free fs/io_uring.c:7870 [inline] io_ring_exit_work+0x195/0x520 fs/io_uring.c:7954 process_one_work+0x789/0xfc0 kernel/workqueue.c:2269 worker_thread+0xaa4/0x1460 kernel/workqueue.c:2415 kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 The buggy address belongs to the object at ffff88821aaa3800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 140 bytes inside of 1024-byte region [ffff88821aaa3800, ffff88821aaa3c00) The buggy address belongs to the page: page:00000000be451134 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x21aaa3 flags: 0x57ffe0000000200(slab) raw: 057ffe0000000200 ffffea00086a2148 ffffea0008536b08 ffff8880aa440700 raw: 0000000000000000 ffff88821aaa3000 0000000100000002 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88821aaa3780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88821aaa3800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88821aaa3880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88821aaa3900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88821aaa3980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches
