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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 f3ff00000c025378 by task kworker/0:2/3909
Pointer tag: [f3], memory tag: [fe]

CPU: 0 PID: 3909 Comm: kworker/0:2 Not tainted 5.11.0-syzkaller #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+0x18/0x70 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+0x134/0x380 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+0x178/0x1bc arch/arm64/mm/fault.c:369
 do_bad_area arch/arm64/mm/fault.c:462 [inline]
 do_tag_check_fault+0x74/0x90 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+0xac/0xd0 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+0x14/0x20 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+0x30/0xa4 fs/ext4/super.c:727
 process_one_work+0x1d8/0x360 kernel/workqueue.c:2275
 worker_thread+0x70/0x434 kernel/workqueue.c:2421
 kthread+0x174/0x180 kernel/kthread.c:292
 ret_from_fork+0x10/0x34 arch/arm64/kernel/entry.S:958

Allocated by task 10512:
 stack_trace_save+0x50/0x80 kernel/stacktrace.c:121
 kasan_save_stack+0x28/0x60 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+0x14/0x20 mm/kasan/common.c:443
 kasan_kmalloc include/linux/kasan.h:219 [inline]
 kmem_cache_alloc_trace include/linux/slab.h:450 [inline]
 kmalloc include/linux/slab.h:552 [inline]
 kzalloc include/linux/slab.h:682 [inline]
 ext4_fill_super+0x90/0x3520 fs/ext4/super.c:4011
 mount_bdev+0x1c0/0x1f0 fs/super.c:1366
 ext4_mount+0x18/0x24 fs/ext4/super.c:6593
 legacy_get_tree+0x30/0x60 fs/fs_context.c:592
 vfs_get_tree+0x28/0xf0 fs/super.c:1496
 do_new_mount fs/namespace.c:2881 [inline]
 path_mount+0x3e8/0xaf0 fs/namespace.c:3211
 do_mount fs/namespace.c:3224 [inline]
 __do_sys_mount fs/namespace.c:3432 [inline]
 __se_sys_mount fs/namespace.c:3409 [inline]
 __arm64_sys_mount+0x1a8/0x2fc fs/namespace.c:3409
 __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+0x74/0x90 arch/arm64/kernel/syscall.c:198
 el0_svc+0x14/0x20 arch/arm64/kernel/entry-common.c:365
 el0_sync_handler+0x1a4/0x1b0 arch/arm64/kernel/entry-common.c:381
 el0_sync+0x190/0x1c0 arch/arm64/kernel/entry.S:699

Freed by task 10512:
 stack_trace_save+0x50/0x80 kernel/stacktrace.c:121
 kasan_save_stack+0x28/0x60 mm/kasan/common.c:38
 kasan_set_track+0x28/0x40 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/hw_tags.c:174
 ____kasan_slab_free.constprop.0+0x184/0x1c0 mm/kasan/common.c:362
 __kasan_slab_free+0x10/0x20 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+0x98/0x18c mm/slub.c:1580
 slab_free mm/slub.c:3143 [inline]
 kfree+0x324/0x4a0 mm/slub.c:4139
 ext4_fill_super+0x350/0x3520 fs/ext4/super.c:5175
 mount_bdev+0x1c0/0x1f0 fs/super.c:1366
 ext4_mount+0x18/0x24 fs/ext4/super.c:6593
 legacy_get_tree+0x30/0x60 fs/fs_context.c:592
 vfs_get_tree+0x28/0xf0 fs/super.c:1496
 do_new_mount fs/namespace.c:2881 [inline]
 path_mount+0x3e8/0xaf0 fs/namespace.c:3211
 do_mount fs/namespace.c:3224 [inline]
 __do_sys_mount fs/namespace.c:3432 [inline]
 __se_sys_mount fs/namespace.c:3409 [inline]
 __arm64_sys_mount+0x1a8/0x2fc fs/namespace.c:3409
 __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+0x74/0x90 arch/arm64/kernel/syscall.c:198
 el0_svc+0x14/0x20 arch/arm64/kernel/entry-common.c:365
 el0_sync_handler+0x1a4/0x1b0 arch/arm64/kernel/entry-common.c:381
 el0_sync+0x190/0x1c0 arch/arm64/kernel/entry.S:699

The buggy address belongs to the object at ffff00000c025000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 888 bytes inside of
 2048-byte region [ffff00000c025000, ffff00000c025800)
The buggy address belongs to the page:
page:0000000099cb5bec refcount:1 mapcount:0 mapping:0000000000000000 index:0xf3ff00000c025000 pfn:0x4c020
head:0000000099cb5bec order:3 compound_mapcount:0 compound_pincount:0
flags: 0x1ffffc000010200(slab|head)
raw: 01ffffc000010200 fffffc0000973808 fffffc0000972a08 f3ff000004801a00
raw: f3ff00000c025000 0000000000080007 00000001ffffffff f3ff0000254be601
page dumped because: kasan: bad access detected
pages's memcg:f3ff0000254be601

Memory state around the buggy address:
 ffff00000c025100: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff00000c025200: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
>ffff00000c025300: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                        ^
 ffff00000c025400: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff00000c025500: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
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