RBP: 00007ffd5571d020 R08: 00007ffd5571e020 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd5571e0b0 R13: 00007faab2bb371f R14: 0000000000018b31 R15: 00007ffd5571e0f0 ================================================================== 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 ffff88805f5db090 by task syz-executor/4187 CPU: 1 PID: 4187 Comm: syz-executor 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 gfs2_sync_fs+0x48/0xb0 fs/gfs2/super.c:647 sync_filesystem+0xe6/0x220 fs/sync.c:56 generic_shutdown_super+0x6b/0x300 fs/super.c:448 kill_block_super+0x7c/0xe0 fs/super.c:1427 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x42d/0x4e0 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 RIP: 0033:0x7faab2b4af17 Code: a2 c7 05 7c 96 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffd5571cf68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007faab2bb371f RCX: 00007faab2b4af17 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd5571d020 RBP: 00007ffd5571d020 R08: 00007ffd5571e020 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd5571e0b0 R13: 00007faab2bb371f R14: 0000000000018b31 R15: 00007ffd5571e0f0 Allocated by task 4497: 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 13: 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+0x142/0x210 kernel/softirq.c:477 __local_bh_enable_ip+0x180/0x1c0 kernel/softirq.c:401 spin_unlock_bh include/linux/spinlock.h:409 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:736 [inline] nsim_dev_trap_report_work+0x7c0/0xb40 drivers/net/netdevsim/dev.c:762 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 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 gfs2_sync_fs+0x48/0xb0 fs/gfs2/super.c:647 sync_filesystem+0xe6/0x220 fs/sync.c:56 generic_shutdown_super+0x6b/0x300 fs/super.c:448 kill_block_super+0x7c/0xe0 fs/super.c:1427 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x42d/0x4e0 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 ffff88805f5db000 which belongs to the cache gfs2_quotad of size 272 The buggy address is located 144 bytes inside of 272-byte region [ffff88805f5db000, ffff88805f5db110) The buggy address belongs to the page: page:ffffea00017d76c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5f5db flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 0000000000000000 dead000000000122 ffff888146af13c0 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 4497, ts 104649840047, free_ts 22256429139 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_contig_range+0x96/0xf0 mm/page_alloc.c:9406 destroy_args+0xf0/0xa00 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:1316 do_initcall_level+0x137/0x1f0 init/main.c:1389 do_initcalls+0x4b/0x90 init/main.c:1405 kernel_init_freeable+0x3e9/0x570 init/main.c:1629 kernel_init+0x19/0x1b0 init/main.c:1520 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Memory state around the buggy address: ffff88805f5daf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805f5db000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805f5db080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805f5db100: fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805f5db180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================