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BUG: KASAN: use-after-free in generic_test_bit include/asm-generic/bitops/generic-non-atomic.h:128 [inline]
BUG: KASAN: use-after-free in gfs2_withdrawn fs/gfs2/util.h:208 [inline]
BUG: KASAN: use-after-free in quotad_error+0x7c/0x18c fs/gfs2/quota.c:1506
Read of size 8 at addr ffff0000dc7ec0a8 by task gfs2_quotad/4469

CPU: 1 PID: 4469 Comm: gfs2_quotad Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/02/2026
Call trace:
 dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106
 print_address_description+0x88/0x218 mm/kasan/report.c:316
 print_report+0x50/0x68 mm/kasan/report.c:420
 kasan_report+0xa8/0xfc mm/kasan/report.c:524
 __asan_report_load8_noabort+0x2c/0x38 mm/kasan/report_generic.c:351
 generic_test_bit include/asm-generic/bitops/generic-non-atomic.h:128 [inline]
 gfs2_withdrawn fs/gfs2/util.h:208 [inline]
 quotad_error+0x7c/0x18c fs/gfs2/quota.c:1506
 quotad_check_timeo fs/gfs2/quota.c:1520 [inline]
 gfs2_quotad+0x320/0x520 fs/gfs2/quota.c:1566
 kthread+0x254/0x2e0 kernel/kthread.c:376
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850

Allocated by task 4455:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:53
 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505
 ____kasan_kmalloc mm/kasan/common.c:375 [inline]
 __kasan_kmalloc+0xa0/0xb8 mm/kasan/common.c:384
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 kmalloc_trace+0x7c/0x94 mm/slab_common.c:1031
 kmalloc include/linux/slab.h:563 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 init_sbd fs/gfs2/ops_fstype.c:77 [inline]
 gfs2_fill_super+0x10c/0x19e0 fs/gfs2/ops_fstype.c:1148
 get_tree_bdev+0x35c/0x54c fs/super.c:1366
 gfs2_get_tree+0x58/0x1b8 fs/gfs2/ops_fstype.c:1327
 vfs_get_tree+0x90/0x278 fs/super.c:1573
 do_new_mount+0x228/0x804 fs/namespace.c:3078
 path_mount+0x5ac/0xe6c fs/namespace.c:3408
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount fs/namespace.c:3606 [inline]
 __arm64_sys_mount+0x4a0/0x5a0 fs/namespace.c:3606
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Freed by task 4337:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:53
 kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:516
 ____kasan_slab_free+0x148/0x1b0 mm/kasan/common.c:237
 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:245
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x16c/0x1e8 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 __kmem_cache_free+0xbc/0x21c mm/slub.c:3700
 kfree+0xd0/0x1a8 mm/slab_common.c:988
 free_sbd+0x5c/0x6c fs/gfs2/ops_fstype.c:69
 gfs2_put_super+0x6dc/0x744 fs/gfs2/super.c:649
 generic_shutdown_super+0x138/0x32c fs/super.c:501
 kill_block_super+0x78/0xe0 fs/super.c:1470
 gfs2_kill_sb+0xc4/0xd8 fs/gfs2/ops_fstype.c:-1
 deactivate_locked_super+0xb4/0x128 fs/super.c:332
 deactivate_super+0xe4/0x104 fs/super.c:363
 cleanup_mnt+0x3a8/0x430 fs/namespace.c:1191
 __cleanup_mnt+0x20/0x30 fs/namespace.c:1198
 task_work_run+0x1f4/0x280 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 do_notify_resume+0x20f8/0x2c84 arch/arm64/kernel/signal.c:1151
 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline]
 el0_svc+0x98/0x128 arch/arm64/kernel/entry-common.c:638
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the object at ffff0000dc7ec000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 168 bytes inside of
 8192-byte region [ffff0000dc7ec000, ffff0000dc7ee000)

The buggy address belongs to the physical page:
page:000000001fdf988d refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11c7e8
head:000000001fdf988d order:3 compound_mapcount:0 compound_pincount:0
flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000010200 fffffc000371f800 dead000000000004 ffff0000c0002c00
raw: 0000000000000000 0000000000020002 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000dc7ebf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff0000dc7ec000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff0000dc7ec080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff0000dc7ec100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff0000dc7ec180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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