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BUG: KASAN: use-after-free in atomic64_inc include/asm-generic/atomic-instrumented.h:1049 [inline]
BUG: KASAN: use-after-free in atomic_long_inc include/asm-generic/atomic-long.h:160 [inline]
BUG: KASAN: use-after-free in fsnotify_detach_connector_from_object+0x25e/0x380 fs/notify/mark.c:185
Write of size 8 at addr ffff8880935b87c0 by task syz-executor.3/16003

CPU: 0 PID: 16003 Comm: syz-executor.3 Not tainted 5.7.0-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+0x188/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd3/0x413 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 check_memory_region_inline mm/kasan/generic.c:186 [inline]
 check_memory_region+0x141/0x190 mm/kasan/generic.c:192
 atomic64_inc include/asm-generic/atomic-instrumented.h:1049 [inline]
 atomic_long_inc include/asm-generic/atomic-long.h:160 [inline]
 fsnotify_detach_connector_from_object+0x25e/0x380 fs/notify/mark.c:185
 fsnotify_put_mark+0x367/0x580 fs/notify/mark.c:250
 fsnotify_clear_marks_by_group+0x33f/0x490 fs/notify/mark.c:764
 fsnotify_destroy_group+0xc9/0x300 fs/notify/group.c:61
 inotify_release+0x33/0x40 fs/notify/inotify/inotify_user.c:271
 __fput+0x33e/0x880 fs/file_table.c:281
 task_work_run+0xf4/0x1b0 kernel/task_work.c:123
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2fa/0x360 arch/x86/entry/common.c:165
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
 do_syscall_64+0x6b1/0x7d0 arch/x86/entry/common.c:305
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x416661
Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 1b 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:0000000000c9fbe0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000416661
RDX: 0000000000000001 RSI: 0000000000000080 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000c9fcd0 R11: 0000000000000293 R12: 00000000007909e8
R13: 000000000003e03c R14: ffffffffffffffff R15: 000000000078bfac

Allocated by task 16022:
 save_stack+0x1b/0x40 mm/kasan/common.c:48
 set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc mm/kasan/common.c:494 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:467
 kmem_cache_alloc_trace+0x153/0x7d0 mm/slab.c:3551
 kmalloc include/linux/slab.h:555 [inline]
 kzalloc include/linux/slab.h:669 [inline]
 alloc_super+0x52/0x9d0 fs/super.c:203
 sget_fc+0x13f/0x790 fs/super.c:530
 vfs_get_super+0x6d/0x2d0 fs/super.c:1186
 vfs_get_tree+0x89/0x2f0 fs/super.c:1547
 do_new_mount fs/namespace.c:2874 [inline]
 do_mount+0x1306/0x1b40 fs/namespace.c:3199
 __do_sys_mount fs/namespace.c:3409 [inline]
 __se_sys_mount fs/namespace.c:3386 [inline]
 __x64_sys_mount+0x18f/0x230 fs/namespace.c:3386
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

Freed by task 2505:
 save_stack+0x1b/0x40 mm/kasan/common.c:48
 set_track mm/kasan/common.c:56 [inline]
 kasan_set_free_info mm/kasan/common.c:316 [inline]
 __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:455
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x109/0x2b0 mm/slab.c:3757
 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268
 worker_thread+0x96/0xe20 kernel/workqueue.c:2414
 kthread+0x388/0x470 kernel/kthread.c:268
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351

The buggy address belongs to the object at ffff8880935b8000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 1984 bytes inside of
 4096-byte region [ffff8880935b8000, ffff8880935b9000)
The buggy address belongs to the page:
page:ffffea00024d6e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 head:ffffea00024d6e00 order:1 compound_mapcount:0
flags: 0xfffe0000010200(slab|head)
raw: 00fffe0000010200 ffffea00018c9f08 ffffea0002987588 ffff8880aa002000
raw: 0000000000000000 ffff8880935b8000 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880935b8680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880935b8700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880935b8780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff8880935b8800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880935b8880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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