BUG: KASAN: use-after-free in __list_del_entry_valid+0x2b/0x100 lib/list_debug.c:42 Read of size 8 at addr ffff8881d4de8280 by task syz-executor.4/24988 CPU: 0 PID: 24988 Comm: syz-executor.4 Tainted: G W 5.4.63-syzkaller-01128-g0ef1db7b69dd #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+0x1b0/0x21e lib/dump_stack.c:118 print_address_description+0x96/0x5d0 mm/kasan/report.c:374 __kasan_report+0x14b/0x1c0 mm/kasan/report.c:506 kasan_report+0x27/0x50 mm/kasan/common.c:634 __list_del_entry_valid+0x2b/0x100 lib/list_debug.c:42 __list_del_entry include/linux/list.h:131 [inline] list_del_init include/linux/list.h:190 [inline] io_cancel_async_work+0x9b/0x280 fs/io_uring.c:3725 io_ring_ctx_wait_and_kill+0xaf/0x1380 fs/io_uring.c:3739 io_uring_release+0x59/0x70 fs/io_uring.c:3762 __fput+0x27d/0x6c0 fs/file_table.c:280 task_work_run+0x176/0x1a0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop arch/x86/entry/common.c:163 [inline] prepare_exit_to_usermode+0x286/0x2e0 arch/x86/entry/common.c:194 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d60a Code: 89 f5 41 54 49 89 fc 55 53 74 35 49 63 e8 48 63 da 4d 89 f9 49 89 e8 4d 63 d6 48 89 da 4c 89 ee 4c 89 e7 b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 4e 5b 5d 41 5c 41 5d 41 5e 41 5f c3 0f 1f 00 RSP: 002b:00007f6359219bc8 EFLAGS: 00000206 ORIG_RAX: 0000000000000009 RAX: 0000000020fff000 RBX: 0000000000000003 RCX: 000000000045d60a RDX: 0000000000000003 RSI: 0000000000200000 RDI: 0000000020fff000 RBP: 000000000000000b R08: 000000000000000b R09: 0000000010000000 R10: 0000000000008011 R11: 0000000000000206 R12: 0000000020fff000 R13: 0000000000200000 R14: 0000000000008011 R15: 0000000010000000 Allocated by task 24983: save_stack mm/kasan/common.c:69 [inline] set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc+0x117/0x1b0 mm/kasan/common.c:510 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slub.c:2793 [inline] slab_alloc mm/slub.c:2801 [inline] kmem_cache_alloc+0x1d5/0x250 mm/slub.c:2806 io_get_req+0x1e8/0x850 fs/io_uring.c:642 io_submit_sqe+0x83/0xe90 fs/io_uring.c:2569 io_ring_submit fs/io_uring.c:2957 [inline] __do_sys_io_uring_enter fs/io_uring.c:3834 [inline] __se_sys_io_uring_enter+0x8ce/0x1f80 fs/io_uring.c:3795 do_syscall_64+0xcb/0x150 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 382: save_stack mm/kasan/common.c:69 [inline] set_track mm/kasan/common.c:77 [inline] kasan_set_free_info mm/kasan/common.c:332 [inline] __kasan_slab_free+0x168/0x220 mm/kasan/common.c:471 slab_free_hook mm/slub.c:1443 [inline] slab_free_freelist_hook+0xd0/0x150 mm/slub.c:1476 slab_free mm/slub.c:3041 [inline] kmem_cache_free+0xac/0x5c0 mm/slub.c:3057 io_put_req fs/io_uring.c:762 [inline] io_poll_complete_work+0x725/0x930 fs/io_uring.c:1835 process_one_work+0x777/0xf90 kernel/workqueue.c:2274 worker_thread+0xa8f/0x1430 kernel/workqueue.c:2420 kthread+0x317/0x340 kernel/kthread.c:268 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 The buggy address belongs to the object at ffff8881d4de8180 which belongs to the cache io_kiocb of size 264 The buggy address is located 256 bytes inside of 264-byte region [ffff8881d4de8180, ffff8881d4de8288) The buggy address belongs to the page: page:ffffea0007537a00 refcount:1 mapcount:0 mapping:ffff8881da1f6280 index:0x0 compound_mapcount: 0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881da1f6280 raw: 0000000000000000 0000000080150015 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881d4de8180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881d4de8200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881d4de8280: fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881d4de8300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881d4de8380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================