================================================================== BUG: KASAN: use-after-free in __list_del_entry_valid+0x2b/0x100 lib/list_debug.c:42 Read of size 8 at addr ffff8881cdc22b80 by task syz-executor842/330 CPU: 0 PID: 330 Comm: syz-executor842 Not tainted 5.4.59-syzkaller-00509-g013a1a228267 #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+0x14a/0x1ce lib/dump_stack.c:118 print_address_description+0x93/0x620 mm/kasan/report.c:374 __kasan_report+0x16d/0x1e0 mm/kasan/report.c:506 kasan_report+0x36/0x60 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:3716 io_ring_ctx_wait_and_kill+0xaf/0x1380 fs/io_uring.c:3730 io_uring_release+0x59/0x70 fs/io_uring.c:3753 __fput+0x27d/0x6c0 fs/file_table.c:280 task_work_run+0x176/0x1a0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xc42/0x2700 kernel/exit.c:808 do_group_exit+0x155/0x2b0 kernel/exit.c:906 __do_sys_exit_group+0x13/0x20 kernel/exit.c:917 __se_sys_exit_group+0x10/0x10 kernel/exit.c:915 __x64_sys_exit_group+0x37/0x40 kernel/exit.c:915 do_syscall_64+0xcb/0x150 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x43f998 Code: Bad RIP value. RSP: 002b:00007ffd6753e468 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 000000000043f998 RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001 RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d11a0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 330: save_stack mm/kasan/common.c:69 [inline] set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc+0x12c/0x1c0 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+0x1d5/0x260 mm/slub.c:2806 io_get_req+0x1e8/0x850 fs/io_uring.c:642 io_submit_sqe+0x83/0xe90 fs/io_uring.c:2560 io_ring_submit fs/io_uring.c:2948 [inline] __do_sys_io_uring_enter fs/io_uring.c:3825 [inline] __se_sys_io_uring_enter+0x922/0x1ff0 fs/io_uring.c:3786 do_syscall_64+0xcb/0x150 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 154: 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+0x181/0x230 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/0x600 mm/slub.c:3057 io_put_req fs/io_uring.c:762 [inline] io_poll_complete_work+0x737/0x940 fs/io_uring.c:1835 process_one_work+0x777/0xf90 kernel/workqueue.c:2274 worker_thread+0xa8f/0x1430 kernel/workqueue.c:2420 kthread+0x2df/0x300 kernel/kthread.c:255 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 The buggy address belongs to the object at ffff8881cdc22a80 which belongs to the cache io_kiocb of size 264 The buggy address is located 256 bytes inside of 264-byte region [ffff8881cdc22a80, ffff8881cdc22b88) The buggy address belongs to the page: page:ffffea0007370880 refcount:1 mapcount:0 mapping:ffff8881d920cf00 index:0x0 compound_mapcount: 0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881d920cf00 raw: 0000000000000000 0000000080150015 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881cdc22a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881cdc22b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881cdc22b80: fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881cdc22c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881cdc22c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==========================================================