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BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
BUG: KASAN: use-after-free in atomic64_try_cmpxchg_acquire include/asm-generic/atomic-instrumented.h:1515 [inline]
BUG: KASAN: use-after-free in atomic_long_try_cmpxchg_acquire include/asm-generic/atomic-long.h:443 [inline]
BUG: KASAN: use-after-free in __down_read_trylock kernel/locking/rwsem.c:1393 [inline]
BUG: KASAN: use-after-free in down_read_trylock+0x83/0x150 kernel/locking/rwsem.c:1553
Write of size 8 at addr ffff888123c95070 by task kworker/u4:3/297

CPU: 0 PID: 297 Comm: kworker/u4:3 Not tainted 5.10.240-syzkaller-00225-g1154f779f3f3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: writeback wb_workfn (flush-7:8)
Call Trace:
 __dump_stack+0x21/0x24 lib/dump_stack.c:77
 dump_stack_lvl+0x169/0x1d8 lib/dump_stack.c:118
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:435 [inline]
 kasan_report+0xe2/0x130 mm/kasan/report.c:452
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x280/0x290 mm/kasan/generic.c:189
 __kasan_check_write+0x14/0x20 mm/kasan/shadow.c:37
 instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
 atomic64_try_cmpxchg_acquire include/asm-generic/atomic-instrumented.h:1515 [inline]
 atomic_long_try_cmpxchg_acquire include/asm-generic/atomic-long.h:443 [inline]
 __down_read_trylock kernel/locking/rwsem.c:1393 [inline]
 down_read_trylock+0x83/0x150 kernel/locking/rwsem.c:1553
 trylock_super+0x1f/0xf0 fs/super.c:418
 __writeback_inodes_wb fs/fs-writeback.c:1795 [inline]
 wb_writeback+0x485/0xb90 fs/fs-writeback.c:1910
 wb_check_background_flush fs/fs-writeback.c:1978 [inline]
 wb_do_writeback fs/fs-writeback.c:2066 [inline]
 wb_workfn+0xa28/0xe20 fs/fs-writeback.c:2094
 process_one_work+0x6e1/0xba0 kernel/workqueue.c:2301
 worker_thread+0xa6a/0x13b0 kernel/workqueue.c:2447
 kthread+0x346/0x3d0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

Allocated by task 3934:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:430 [inline]
 ____kasan_kmalloc mm/kasan/common.c:509 [inline]
 __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:518
 kasan_kmalloc include/linux/kasan.h:254 [inline]
 kmem_cache_alloc_trace+0x184/0x2e0 mm/slub.c:2974
 kmalloc include/linux/slab.h:552 [inline]
 kzalloc include/linux/slab.h:664 [inline]
 alloc_super+0x5e/0x7a0 fs/super.c:203
 sget+0x1e4/0x4c0 fs/super.c:627
 mount_bdev+0xf6/0x3a0 fs/super.c:1415
 f2fs_mount+0x34/0x40 fs/f2fs/super.c:4562
 legacy_get_tree+0xed/0x190 fs/fs_context.c:593
 vfs_get_tree+0x89/0x260 fs/super.c:1572
 do_new_mount+0x25a/0xa20 fs/namespace.c:2919
 path_mount+0x572/0xc80 fs/namespace.c:3249
 do_mount fs/namespace.c:3262 [inline]
 __do_sys_mount fs/namespace.c:3470 [inline]
 __se_sys_mount+0x318/0x380 fs/namespace.c:3447
 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3447
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Freed by task 348:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4a/0x70 mm/kasan/common.c:45
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:362
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:370
 kasan_slab_free include/linux/kasan.h:220 [inline]
 slab_free_hook mm/slub.c:1595 [inline]
 slab_free_freelist_hook+0xc5/0x190 mm/slub.c:1621
 slab_free mm/slub.c:3203 [inline]
 kfree+0xc0/0x270 mm/slub.c:4191
 destroy_super_work+0x40/0x50 fs/super.c:165
 process_one_work+0x6e1/0xba0 kernel/workqueue.c:2301
 worker_thread+0xa6a/0x13b0 kernel/workqueue.c:2447
 kthread+0x346/0x3d0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

Last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358
 insert_work+0x52/0x310 kernel/workqueue.c:1352
 __queue_work+0x923/0xca0 kernel/workqueue.c:1518
 queue_work_on+0xd5/0x130 kernel/workqueue.c:1545
 queue_work include/linux/workqueue.h:515 [inline]
 schedule_work include/linux/workqueue.h:576 [inline]
 destroy_super_rcu+0xd1/0xe0 fs/super.c:172
 rcu_do_batch+0x4df/0xa80 kernel/rcu/tree.c:2494
 rcu_core+0x55f/0xd60 kernel/rcu/tree.c:2735
 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2748
 __do_softirq+0x255/0x563 kernel/softirq.c:309

Second to last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358
 __call_rcu kernel/rcu/tree.c:2980 [inline]
 call_rcu+0x10e/0x1050 kernel/rcu/tree.c:3054
 __put_super+0x254/0x2b0 fs/super.c:299
 put_super fs/super.c:313 [inline]
 deactivate_locked_super+0xd4/0x100 fs/super.c:346
 deactivate_super+0xaf/0xe0 fs/super.c:366
 cleanup_mnt+0x446/0x500 fs/namespace.c:1114
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1121
 task_work_run+0x127/0x190 kernel/task_work.c:189
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop+0xcb/0xe0 kernel/entry/common.c:172
 exit_to_user_mode_prepare kernel/entry/common.c:199 [inline]
 syscall_exit_to_user_mode+0x68/0x90 kernel/entry/common.c:274
 do_syscall_64+0x3d/0x40 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

The buggy address belongs to the object at ffff888123c95000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 112 bytes inside of
 2048-byte region [ffff888123c95000, ffff888123c95800)
The buggy address belongs to the page:
page:ffffea00048f2400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x123c90
head:ffffea00048f2400 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head)
raw: 4000000000010200 ffffea0004543e00 0000000300000003 ffff888100042d80
raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 1854, ts 533240064282, free_ts 531768502130
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook mm/page_alloc.c:2456 [inline]
 prep_new_page+0x179/0x180 mm/page_alloc.c:2462
 get_page_from_freelist+0x2235/0x23d0 mm/page_alloc.c:4254
 __alloc_pages_nodemask+0x268/0x5f0 mm/page_alloc.c:5357
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1808 [inline]
 new_slab+0x84/0x3f0 mm/slub.c:1869
 new_slab_objects mm/slub.c:2627 [inline]
 ___slab_alloc+0x2a6/0x450 mm/slub.c:2791
 __slab_alloc+0x63/0xa0 mm/slub.c:2831
 slab_alloc_node mm/slub.c:2913 [inline]
 slab_alloc mm/slub.c:2955 [inline]
 __kmalloc_track_caller+0x1ef/0x320 mm/slub.c:4536
 kmemdup+0x26/0x60 mm/util.c:131
 neigh_sysctl_register+0xaf/0xa70 net/core/neighbour.c:3652
 devinet_sysctl_register+0xaf/0x1e0 net/ipv4/devinet.c:2636
 inetdev_init+0x273/0x480 net/ipv4/devinet.c:277
 inetdev_event+0x1f8/0x1030 net/ipv4/devinet.c:1545
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:410
 call_netdevice_notifiers_info net/core/dev.c:2054 [inline]
 call_netdevice_notifiers_extack net/core/dev.c:2066 [inline]
 call_netdevice_notifiers+0x111/0x190 net/core/dev.c:2080
 register_netdevice+0x1043/0x13c0 net/core/dev.c:10087
 veth_newlink+0x641/0xbb0 drivers/net/veth.c:1360
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:28 [inline]
 free_pages_prepare mm/page_alloc.c:1349 [inline]
 free_pcp_prepare mm/page_alloc.c:1421 [inline]
 free_unref_page_prepare+0x2b7/0x2d0 mm/page_alloc.c:3336
 free_unref_page mm/page_alloc.c:3391 [inline]
 free_the_page mm/page_alloc.c:5416 [inline]
 __free_pages+0x14b/0x380 mm/page_alloc.c:5427
 __vunmap+0x84d/0x9d0 mm/vmalloc.c:2301
 __vfree mm/vmalloc.c:2350 [inline]
 vfree+0x61/0x90 mm/vmalloc.c:2381
 kcov_put kernel/kcov.c:408 [inline]
 kcov_close+0x2b/0x50 kernel/kcov.c:510
 __fput+0x2fb/0x770 fs/file_table.c:281
 ____fput+0x15/0x20 fs/file_table.c:314
 task_work_run+0x127/0x190 kernel/task_work.c:189
 exit_task_work include/linux/task_work.h:33 [inline]
 do_exit+0xa4f/0x2480 kernel/exit.c:872
 do_group_exit+0x141/0x310 kernel/exit.c:986
 get_signal+0xf7d/0x12e0 kernel/signal.c:2793
 arch_do_signal_or_restart+0xbf/0x10f0 arch/x86/kernel/signal.c:805
 handle_signal_work kernel/entry/common.c:145 [inline]
 exit_to_user_mode_loop+0xa2/0xe0 kernel/entry/common.c:169
 exit_to_user_mode_prepare kernel/entry/common.c:199 [inline]
 syscall_exit_to_user_mode+0x68/0x90 kernel/entry/common.c:274
 do_syscall_64+0x3d/0x40 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Memory state around the buggy address:
 ffff888123c94f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888123c94f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888123c95000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff888123c95080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888123c95100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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