Hello, syzbot found the following issue on: HEAD commit: fc80c51f Merge tag 'kbuild-v5.9' of git://git.kernel.org/p.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=17601ab2900000 kernel config: https://syzkaller.appspot.com/x/.config?x=d48472fcc2f68903 dashboard link: https://syzkaller.appspot.com/bug?extid=9b260fc33297966f5a8e compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=174272b2900000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+9b260fc33297966f5a8e@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:56 [inline] BUG: KASAN: use-after-free in atomic64_read include/asm-generic/atomic-instrumented.h:837 [inline] BUG: KASAN: use-after-free in atomic_long_read include/asm-generic/atomic-long.h:29 [inline] BUG: KASAN: use-after-free in __mutex_unlock_slowpath+0x88/0x590 kernel/locking/mutex.c:1237 Read of size 8 at addr ffff8880952503c0 by task syz-executor.1/23201 CPU: 0 PID: 23201 Comm: syz-executor.1 Not tainted 5.8.0-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+0x1f0/0x31e 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_read include/linux/instrumented.h:56 [inline] atomic64_read include/asm-generic/atomic-instrumented.h:837 [inline] atomic_long_read include/asm-generic/atomic-long.h:29 [inline] __mutex_unlock_slowpath+0x88/0x590 kernel/locking/mutex.c:1237 io_async_task_func+0x485/0x610 fs/io_uring.c:4689 task_work_run+0x137/0x1c0 kernel/task_work.c:135 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:139 [inline] exit_to_user_mode_prepare+0xfa/0x1c0 kernel/entry/common.c:166 syscall_exit_to_user_mode+0x5e/0x1a0 kernel/entry/common.c:241 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45ce69 Code: 2d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb b5 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f6719775c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000037 RAX: fffffffffffffffe RBX: 0000000000004f40 RCX: 000000000045ce69 RDX: 0000000000000043 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 000000000118c010 R08: 0000000020000140 R09: 0000000000000000 R10: 0000000020000000 R11: 0000000000000246 R12: 000000000118bfcc R13: 00007fff62cc118f R14: 00007f67197769c0 R15: 000000000118bfcc Allocated by task 23153: 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_trace+0x1f6/0x2f0 mm/slab.c:3550 kmalloc include/linux/slab.h:554 [inline] kzalloc include/linux/slab.h:666 [inline] io_ring_ctx_alloc fs/io_uring.c:1030 [inline] io_uring_create fs/io_uring.c:8308 [inline] io_uring_setup fs/io_uring.c:8401 [inline] __do_sys_io_uring_setup fs/io_uring.c:8407 [inline] __se_sys_io_uring_setup+0x5ce/0x2c70 fs/io_uring.c:8404 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 5: 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+0x10a/0x220 mm/slab.c:3756 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 Last call_rcu(): kasan_save_stack+0x27/0x50 mm/kasan/common.c:48 kasan_record_aux_stack+0x7b/0xb0 mm/kasan/generic.c:346 __call_rcu kernel/rcu/tree.c:2894 [inline] call_rcu+0x139/0x840 kernel/rcu/tree.c:2968 __percpu_ref_switch_to_atomic lib/percpu-refcount.c:192 [inline] __percpu_ref_switch_mode+0x2c1/0x4f0 lib/percpu-refcount.c:237 percpu_ref_kill_and_confirm+0x8f/0x130 lib/percpu-refcount.c:350 percpu_ref_kill include/linux/percpu-refcount.h:136 [inline] io_ring_ctx_wait_and_kill+0x3c/0x570 fs/io_uring.c:7797 io_uring_release+0x59/0x70 fs/io_uring.c:7829 __fput+0x34f/0x7b0 fs/file_table.c:281 task_work_run+0x137/0x1c0 kernel/task_work.c:135 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:139 [inline] exit_to_user_mode_prepare+0xfa/0x1c0 kernel/entry/common.c:166 syscall_exit_to_user_mode+0x5e/0x1a0 kernel/entry/common.c:241 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Second to last call_rcu(): kasan_save_stack+0x27/0x50 mm/kasan/common.c:48 kasan_record_aux_stack+0x7b/0xb0 mm/kasan/generic.c:346 __call_rcu kernel/rcu/tree.c:2894 [inline] call_rcu+0x139/0x840 kernel/rcu/tree.c:2968 __percpu_ref_switch_to_atomic lib/percpu-refcount.c:192 [inline] __percpu_ref_switch_mode+0x2c1/0x4f0 lib/percpu-refcount.c:237 percpu_ref_kill_and_confirm+0x8f/0x130 lib/percpu-refcount.c:350 percpu_ref_kill include/linux/percpu-refcount.h:136 [inline] io_ring_ctx_wait_and_kill+0x3c/0x570 fs/io_uring.c:7797 io_uring_release+0x59/0x70 fs/io_uring.c:7829 __fput+0x34f/0x7b0 fs/file_table.c:281 task_work_run+0x137/0x1c0 kernel/task_work.c:135 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:139 [inline] exit_to_user_mode_prepare+0xfa/0x1c0 kernel/entry/common.c:166 syscall_exit_to_user_mode+0x5e/0x1a0 kernel/entry/common.c:241 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff888095250000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 960 bytes inside of 2048-byte region [ffff888095250000, ffff888095250800) The buggy address belongs to the page: page:000000005a2c89d9 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x95250 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea00024ca6c8 ffffea00024d8c48 ffff8880aa440800 raw: 0000000000000000 ffff888095250000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888095250280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888095250300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888095250380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888095250400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888095250480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== --- This report is generated by a bot. 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