kthread+0x436/0x520 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+0xbee/0xfe0 fs/gfs2/glops.c:487 Write of size 8 at addr ffff8880602a3af0 by task gfs2_quotad/4634 CPU: 1 PID: 4634 Comm: gfs2_quotad Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x230 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+0x27b/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+0xbee/0xfe0 fs/gfs2/glops.c:487 inode_go_lock+0x127/0x470 fs/gfs2/glops.c:510 do_promote+0x741/0xab0 fs/gfs2/glock.c:507 finish_xmote+0x514/0xb70 fs/gfs2/glock.c:678 do_xmote+0x7b6/0x1120 fs/gfs2/glock.c:824 gfs2_glock_nq+0xc7a/0x1550 fs/gfs2/glock.c:1534 gfs2_glock_nq_init fs/gfs2/glock.h:246 [inline] do_sync+0x486/0xc00 fs/gfs2/quota.c:927 gfs2_quota_sync+0x32c/0x6f0 fs/gfs2/quota.c:1329 quotad_check_timeo fs/gfs2/quota.c:1519 [inline] gfs2_quotad+0x3f6/0x880 fs/gfs2/quota.c:1586 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Allocated by task 4626: 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+0x9c/0xd0 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+0x100/0x290 mm/slub.c:3238 gfs2_alloc_inode+0x45/0x110 fs/gfs2/super.c:1447 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+0xe5/0xd00 fs/gfs2/inode.c:140 gfs2_dir_search+0x165/0x220 fs/gfs2/dir.c:1665 gfs2_lookupi+0x45c/0x5e0 fs/gfs2/inode.c:332 gfs2_lookup_simple+0xa3/0xf0 fs/gfs2/inode.c:273 init_inodes+0x180/0x320 fs/gfs2/ops_fstype.c:906 gfs2_fill_super+0x1701/0x1f50 fs/gfs2/ops_fstype.c:1249 get_tree_bdev+0x3f1/0x610 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+0x24a/0xa40 fs/namespace.c:3034 do_mount fs/namespace.c:3377 [inline] __do_sys_mount fs/namespace.c:3585 [inline] __se_sys_mount+0x2d6/0x3c0 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 4613: 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+0xea/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+0x962/0x15d0 kernel/rcu/tree.c:2763 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 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+0x182/0x930 kernel/rcu/tree.c:3091 destroy_inode fs/inode.c:316 [inline] evict+0x7da/0x870 fs/inode.c:662 init_inodes+0x95/0x320 fs/gfs2/ops_fstype.c:926 gfs2_fill_super+0x1840/0x1f50 fs/gfs2/ops_fstype.c:1296 get_tree_bdev+0x3f1/0x610 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+0x24a/0xa40 fs/namespace.c:3034 do_mount fs/namespace.c:3377 [inline] __do_sys_mount fs/namespace.c:3585 [inline] __se_sys_mount+0x2d6/0x3c0 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 The buggy address belongs to the object at ffff8880602a3640 which belongs to the cache gfs2_inode of size 1608 The buggy address is located 1200 bytes inside of 1608-byte region [ffff8880602a3640, ffff8880602a3c88) The buggy address belongs to the page: page:ffffea000180a800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x602a0 head:ffffea000180a800 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff88802041d001 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff8881464ff140 raw: 0000000000000000 0000000080120012 00000001ffffffff ffff88802041d001 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 4626, ts 90096769945, free_ts 89036053239 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5487 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+0x81e/0xdf0 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+0x195/0x290 mm/slub.c:3238 gfs2_alloc_inode+0x45/0x110 fs/gfs2/super.c:1447 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+0xe5/0xd00 fs/gfs2/inode.c:140 gfs2_lookup_root fs/gfs2/ops_fstype.c:465 [inline] init_sb+0xa49/0x1330 fs/gfs2/ops_fstype.c:532 gfs2_fill_super+0x13fb/0x1f50 fs/gfs2/ops_fstype.c:1216 get_tree_bdev+0x3f1/0x610 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+0x24a/0xa40 fs/namespace.c:3034 do_mount fs/namespace.c:3377 [inline] __do_sys_mount fs/namespace.c:3585 [inline] __se_sys_mount+0x2d6/0x3c0 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 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+0x94/0x280 mm/page_alloc.c:3396 free_slab mm/slub.c:2020 [inline] discard_slab mm/slub.c:2026 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2512 put_cpu_partial+0x12d/0x190 mm/slub.c:2592 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:444 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] kmem_cache_alloc_node+0x12d/0x2d0 mm/slub.c:3261 __alloc_skb+0xf4/0x750 net/core/skbuff.c:415 alloc_skb include/linux/skbuff.h:1162 [inline] alloc_skb_with_frags+0xa7/0x730 net/core/skbuff.c:6170 sock_alloc_send_pskb+0x853/0x980 net/core/sock.c:2536 unix_dgram_sendmsg+0x5ef/0x1890 net/unix/af_unix.c:1809 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] __sys_sendto+0x423/0x580 net/socket.c:2073 __do_sys_sendto net/socket.c:2085 [inline] __se_sys_sendto net/socket.c:2081 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2081 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 Memory state around the buggy address: ffff8880602a3980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880602a3a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880602a3a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880602a3b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880602a3b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb 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