================================================================== BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline] BUG: KASAN: use-after-free in test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] BUG: KASAN: use-after-free in qd_unlock+0x30/0x2d0 fs/gfs2/quota.c:497 Read of size 8 at addr ffff888074792090 by task gfs2_quotad/5099 CPU: 1 PID: 5099 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+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_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] qd_unlock+0x30/0x2d0 fs/gfs2/quota.c:497 gfs2_quota_sync+0x5cf/0x700 fs/gfs2/quota.c:1336 quotad_check_timeo fs/gfs2/quota.c:1519 [inline] gfs2_quotad+0x403/0x890 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 5074: 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 kmem_cache_zalloc include/linux/slab.h:728 [inline] qd_alloc+0x50/0x260 fs/gfs2/quota.c:216 gfs2_quota_init+0x74e/0xea0 fs/gfs2/quota.c:1426 gfs2_make_fs_rw+0x414/0x580 fs/gfs2/super.c:155 gfs2_fill_super+0x1837/0x1f00 fs/gfs2/ops_fstype.c:1276 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+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 1274: 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+0x9d2/0x1670 kernel/rcu/tree.c:2763 handle_softirqs+0x339/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 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+0x189/0x950 kernel/rcu/tree.c:3091 gfs2_quota_cleanup+0x43c/0x6a0 fs/gfs2/quota.c:1490 gfs2_make_fs_ro+0x440/0x620 fs/gfs2/super.c:557 signal_our_withdraw fs/gfs2/util.c:166 [inline] gfs2_withdraw+0x610/0x1490 fs/gfs2/util.c:343 gfs2_dinode_in fs/gfs2/glops.c:465 [inline] gfs2_inode_refresh+0xb64/0xff0 fs/gfs2/glops.c:485 inode_go_lock+0x127/0x470 fs/gfs2/glops.c:510 do_promote+0x741/0xab0 fs/gfs2/glock.c:507 finish_xmote+0x4df/0xb00 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+0x4ab/0xc40 fs/gfs2/quota.c:927 gfs2_quota_sync+0x32c/0x700 fs/gfs2/quota.c:1329 quotad_check_timeo fs/gfs2/quota.c:1519 [inline] gfs2_quotad+0x403/0x890 fs/gfs2/quota.c:1586 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 The buggy address belongs to the object at ffff888074792000 which belongs to the cache gfs2_quotad of size 272 The buggy address is located 144 bytes inside of 272-byte region [ffff888074792000, ffff888074792110) The buggy address belongs to the page: page:ffffea0001d1e480 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x74792 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 0000000000000000 dead000000000122 ffff88801e53a280 raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Reclaimable, gfp_mask 0x112c50(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 5074, ts 104018533235, free_ts 96326689184 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192 __alloc_pages+0x1ee/0x480 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+0x80a/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+0x195/0x290 mm/slub.c:3238 kmem_cache_zalloc include/linux/slab.h:728 [inline] qd_alloc+0x50/0x260 fs/gfs2/quota.c:216 gfs2_quota_init+0x74e/0xea0 fs/gfs2/quota.c:1426 gfs2_make_fs_rw+0x414/0x580 fs/gfs2/super.c:155 gfs2_fill_super+0x1837/0x1f00 fs/gfs2/ops_fstype.c:1276 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+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 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_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] __kmalloc_node+0x15a/0x3b0 mm/slub.c:4456 kmalloc_node include/linux/slab.h:630 [inline] kvmalloc_node+0x84/0x130 mm/util.c:619 kvmalloc include/linux/mm.h:816 [inline] xt_alloc_table_info+0x37/0xa0 net/netfilter/x_tables.c:1192 do_replace net/ipv4/netfilter/ip_tables.c:1127 [inline] do_ipt_set_ctl+0x86a/0xd80 net/ipv4/netfilter/ip_tables.c:1636 nf_setsockopt+0x25f/0x280 net/netfilter/nf_sockopt.c:101 ip_setsockopt+0x207d/0x3130 net/ipv4/ip_sockglue.c:1442 tcp_setsockopt+0x240/0x1e90 net/ipv4/tcp.c:3719 __sys_setsockopt+0x2bf/0x3d0 net/socket.c:2212 Memory state around the buggy address: ffff888074791f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888074792000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888074792080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888074792100: fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888074792180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================