kthread+0x42e/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 ================================================================== BUG: KASAN: use-after-free in instrument_atomic_write include/linux/instrumented.h:86 [inline] BUG: KASAN: use-after-free in clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline] BUG: KASAN: use-after-free in gfs2_inode_refresh+0xd02/0x11a0 fs/gfs2/glops.c:499 Write of size 8 at addr ffff88805edf1240 by task gfs2_quotad/4405 CPU: 0 PID: 4405 Comm: gfs2_quotad Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x235/0x290 mm/kasan/generic.c:189 instrument_atomic_write include/linux/instrumented.h:86 [inline] clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline] gfs2_inode_refresh+0xd02/0x11a0 fs/gfs2/glops.c:499 inode_go_lock+0x127/0x450 fs/gfs2/glops.c:522 do_promote+0x75b/0xb20 fs/gfs2/glock.c:507 finish_xmote+0x4c2/0xaf0 fs/gfs2/glock.c:678 do_xmote+0x752/0x10a0 fs/gfs2/glock.c:824 gfs2_glock_nq+0xc6b/0x1510 fs/gfs2/glock.c:1534 gfs2_glock_nq_init fs/gfs2/glock.h:246 [inline] do_sync+0x49c/0xba0 fs/gfs2/quota.c:927 gfs2_quota_sync+0x355/0x780 fs/gfs2/quota.c:1329 quotad_check_timeo fs/gfs2/quota.c:1519 [inline] gfs2_quotad+0x40f/0x890 fs/gfs2/quota.c:1586 kthread+0x42e/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Allocated by task 4397: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x92/0xc0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0x15d/0x280 mm/slub.c:3238 gfs2_alloc_inode+0x45/0x110 fs/gfs2/super.c:1451 alloc_inode fs/inode.c:261 [inline] iget5_locked+0x9e/0x250 fs/inode.c:1263 gfs2_iget fs/gfs2/inode.c:64 [inline] gfs2_inode_lookup+0x110/0xd20 fs/gfs2/inode.c:140 gfs2_dir_search+0x165/0x220 fs/gfs2/dir.c:1666 gfs2_lookupi+0x4a1/0x630 fs/gfs2/inode.c:332 gfs2_lookup_simple+0xab/0x100 fs/gfs2/inode.c:273 init_inodes+0x180/0x320 fs/gfs2/ops_fstype.c:906 gfs2_fill_super+0x1671/0x1ea0 fs/gfs2/ops_fstype.c:1249 get_tree_bdev+0x3e6/0x610 fs/super.c:1325 gfs2_get_tree+0x4d/0x1e0 fs/gfs2/ops_fstype.c:1332 vfs_get_tree+0x88/0x270 fs/super.c:1530 do_new_mount+0x247/0xa40 fs/namespace.c:3034 do_mount fs/namespace.c:3377 [inline] __do_sys_mount fs/namespace.c:3585 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 4403: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1710 [inline] slab_free_freelist_hook+0xec/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kmem_cache_free+0x8f/0x210 mm/slub.c:3520 rcu_do_batch kernel/rcu/tree.c:2523 [inline] rcu_core+0x96e/0x1650 kernel/rcu/tree.c:2763 handle_softirqs+0x336/0x830 kernel/softirq.c:576 do_softirq+0x142/0x210 kernel/softirq.c:477 __local_bh_enable_ip+0x180/0x1c0 kernel/softirq.c:401 sock_orphan include/net/sock.h:2094 [inline] unix_release_sock+0x285/0xc60 net/unix/af_unix.c:536 unix_release+0x88/0xc0 net/unix/af_unix.c:944 __sock_release net/socket.c:651 [inline] sock_close+0xbf/0x210 net/socket.c:1346 __fput+0x212/0x8c0 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 get_signal+0x123e/0x12e0 kernel/signal.c:2673 arch_do_signal_or_restart+0xe6/0x12a0 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Last potentially related work creation: kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3011 [inline] call_rcu+0x189/0x900 kernel/rcu/tree.c:3091 destroy_inode fs/inode.c:316 [inline] evict+0x810/0x8b0 fs/inode.c:662 gfs2_put_super+0x2fa/0x7c0 fs/gfs2/super.c:607 generic_shutdown_super+0x130/0x300 fs/super.c:475 kill_block_super+0x7c/0xe0 fs/super.c:1427 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x426/0x4d0 fs/namespace.c:1148 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88805edf0d90 which belongs to the cache gfs2_inode of size 1608 The buggy address is located 1200 bytes inside of 1608-byte region [ffff88805edf0d90, ffff88805edf13d8) The buggy address belongs to the page: page:ffffea00017b7c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5edf0 head:ffffea00017b7c00 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff88801ab81d01 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888146cb3640 raw: 0000000000000000 0000000080120012 00000001ffffffff ffff88801ab81d01 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Reclaimable, gfp_mask 0x1d20d0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 4397, ts 78227920876, free_ts 20904840842 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x24f6/0x2670 mm/page_alloc.c:4192 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501 alloc_slab_page mm/slub.c:1780 [inline] allocate_slab mm/slub.c:1917 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1980 ___slab_alloc+0x807/0xdd0 mm/slub.c:3013 __slab_alloc mm/slub.c:3100 [inline] slab_alloc_node mm/slub.c:3191 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0xf0/0x280 mm/slub.c:3238 gfs2_alloc_inode+0x45/0x110 fs/gfs2/super.c:1451 alloc_inode fs/inode.c:261 [inline] iget5_locked+0x9e/0x250 fs/inode.c:1263 gfs2_iget fs/gfs2/inode.c:64 [inline] gfs2_inode_lookup+0x110/0xd20 fs/gfs2/inode.c:140 gfs2_dir_search+0x165/0x220 fs/gfs2/dir.c:1666 gfs2_lookupi+0x4a1/0x630 fs/gfs2/inode.c:332 gfs2_lookup_simple+0xab/0x100 fs/gfs2/inode.c:273 init_statfs fs/gfs2/ops_fstype.c:681 [inline] init_journal+0x12df/0x22d0 fs/gfs2/ops_fstype.c:822 init_inodes+0xdb/0x320 fs/gfs2/ops_fstype.c:891 gfs2_fill_super+0x1671/0x1ea0 fs/gfs2/ops_fstype.c:1249 get_tree_bdev+0x3e6/0x610 fs/super.c:1325 gfs2_get_tree+0x4d/0x1e0 fs/gfs2/ops_fstype.c:1332 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396 free_contig_range+0x96/0xf0 mm/page_alloc.c:9428 destroy_args+0xef/0xa00 mm/debug_vm_pgtable.c:1018 debug_vm_pgtable+0x321/0x380 mm/debug_vm_pgtable.c:1336 do_one_initcall+0x272/0x730 init/main.c:1315 do_initcall_level+0x13d/0x1f0 init/main.c:1388 do_initcalls+0x4b/0x90 init/main.c:1404 kernel_init_freeable+0x3d5/0x560 init/main.c:1628 kernel_init+0x19/0x1b0 init/main.c:1519 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Memory state around the buggy address: ffff88805edf1100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805edf1180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805edf1200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805edf1280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805edf1300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================