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BUG: KASAN: invalid-access in hlist_add_head include/linux/list.h:883 [inline]
BUG: KASAN: invalid-access in enqueue_timer+0x18/0xc0 kernel/time/timer.c:581
Write at addr fcff000006170378 by task kworker/1:2/25204
Pointer tag: [fc], memory tag: [f9]

CPU: 1 PID: 25204 Comm: kworker/1:2 Not tainted 5.11.0-rc5-syzkaller-00303-g0e9bcda5d286 #0
Hardware name: linux,dummy-virt (DT)
Workqueue: events flush_stashed_error_work
Call trace:
 dump_backtrace+0x0/0x1b0 arch/arm64/kernel/stacktrace.c:117
 show_stack+0x1c/0x70 arch/arm64/kernel/stacktrace.c:196
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0xd0/0x12c lib/dump_stack.c:120
 print_address_description+0x70/0x29c mm/kasan/report.c:230
 __kasan_report mm/kasan/report.c:396 [inline]
 kasan_report+0x104/0x200 mm/kasan/report.c:413
 report_tag_fault arch/arm64/mm/fault.c:311 [inline]
 do_tag_recovery arch/arm64/mm/fault.c:325 [inline]
 __do_kernel_fault+0x17c/0x1c0 arch/arm64/mm/fault.c:369
 do_bad_area arch/arm64/mm/fault.c:462 [inline]
 do_tag_check_fault+0x78/0x8c arch/arm64/mm/fault.c:717
 do_mem_abort+0x44/0xbc arch/arm64/mm/fault.c:793
 el1_abort+0x40/0x6c arch/arm64/kernel/entry-common.c:118
 el1_sync_handler+0xb0/0xcc arch/arm64/kernel/entry-common.c:209
 el1_sync+0x70/0x100 arch/arm64/kernel/entry.S:656
 hlist_add_head include/linux/list.h:883 [inline]
 enqueue_timer+0x18/0xc0 kernel/time/timer.c:581
 mod_timer+0x18/0x24 kernel/time/timer.c:1106
 ext4_update_super+0x324/0x370 fs/ext4/super.c:5537
 ext4_commit_super+0x74/0x184 fs/ext4/super.c:5555
 flush_stashed_error_work+0x34/0xb0 fs/ext4/super.c:727
 process_one_work+0x1d8/0x360 kernel/workqueue.c:2275
 worker_thread+0x74/0x440 kernel/workqueue.c:2421
 kthread+0x178/0x180 kernel/kthread.c:292
 ret_from_fork+0x10/0x30 arch/arm64/kernel/entry.S:958

Allocated by task 4586:
 stack_trace_save+0x50/0x80 kernel/stacktrace.c:121
 kasan_save_stack+0x2c/0x60 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:401 [inline]
 ____kasan_kmalloc+0xe8/0x160 mm/kasan/common.c:429
 __kasan_kmalloc+0x18/0x24 mm/kasan/common.c:443
 kasan_kmalloc include/linux/kasan.h:219 [inline]
 __kmalloc_node+0x1d0/0x3ac mm/slub.c:4019
 kmalloc_node include/linux/slab.h:575 [inline]
 kvmalloc_node+0x44/0xec mm/util.c:587
 kvmalloc include/linux/mm.h:781 [inline]
 kvmalloc_array include/linux/mm.h:799 [inline]
 alloc_fdtable+0xb0/0x150 fs/file.c:118
 dup_fd+0x244/0x324 fs/file.c:323
 copy_files kernel/fork.c:1466 [inline]
 copy_process+0x5e8/0x14f0 kernel/fork.c:2085
 kernel_clone+0x5c/0x3c0 kernel/fork.c:2462
 __do_sys_clone+0x54/0x80 kernel/fork.c:2579
 __se_sys_clone kernel/fork.c:2547 [inline]
 __arm64_sys_clone+0x24/0x30 kernel/fork.c:2547
 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]
 invoke_syscall arch/arm64/kernel/syscall.c:49 [inline]
 el0_svc_common.constprop.0+0x74/0x190 arch/arm64/kernel/syscall.c:159
 do_el0_svc+0x78/0x90 arch/arm64/kernel/syscall.c:198
 el0_svc+0x14/0x20 arch/arm64/kernel/entry-common.c:365
 el0_sync_handler+0x1a8/0x1b0 arch/arm64/kernel/entry-common.c:381
 el0_sync+0x190/0x1c0 arch/arm64/kernel/entry.S:699

Freed by task 27486:
 stack_trace_save+0x50/0x80 kernel/stacktrace.c:121
 kasan_save_stack+0x2c/0x60 mm/kasan/common.c:38
 kasan_set_track+0x2c/0x40 mm/kasan/common.c:46
 kasan_set_free_info+0x24/0x30 mm/kasan/hw_tags.c:178
 ____kasan_slab_free.constprop.0+0x184/0x1c0 mm/kasan/common.c:362
 __kasan_slab_free+0x14/0x20 mm/kasan/common.c:369
 kasan_slab_free include/linux/kasan.h:192 [inline]
 slab_free_hook mm/slub.c:1547 [inline]
 slab_free_freelist_hook+0x9c/0x190 mm/slub.c:1580
 slab_free mm/slub.c:3143 [inline]
 kfree+0x328/0x4a4 mm/slub.c:4125
 kvfree+0x40/0x50 mm/util.c:616
 __free_fdtable fs/file.c:34 [inline]
 put_files_struct fs/file.c:420 [inline]
 put_files_struct+0xc8/0x12c fs/file.c:413
 exit_files+0x44/0x60 fs/file.c:433
 do_exit+0x724/0xa34 kernel/exit.c:820
 do_group_exit+0x3c/0xa0 kernel/exit.c:922
 get_signal+0x14c/0x740 kernel/signal.c:2773
 do_signal arch/arm64/kernel/signal.c:882 [inline]
 do_notify_resume+0x170/0x13e0 arch/arm64/kernel/signal.c:936
 work_pending+0xc/0x3d4

The buggy address belongs to the object at ffff000006170000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 888 bytes inside of
 2048-byte region [ffff000006170000, ffff000006170800)
The buggy address belongs to the page:
page:000000001e98534c refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x46170
head:000000001e98534c order:3 compound_mapcount:0 compound_pincount:0
flags: 0x1ffffc000010200(slab|head)
raw: 01ffffc000010200 0000000000000000 0000000100000001 f7ff000004001a00
raw: 0000000000000000 0000000000080008 00000001ffffffff f2ff00002496a901
page dumped because: kasan: bad access detected
pages's memcg:f2ff00002496a901

Memory state around the buggy address:
 ffff000006170100: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
 ffff000006170200: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
>ffff000006170300: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
                                        ^
 ffff000006170400: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
 ffff000006170500: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
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