================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x106/0x7d10 kernel/locking/lockdep.c:4919 Read of size 8 at addr ffff88805b3ccbb0 by task gfs2_quotad/17465 CPU: 0 PID: 17465 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+0x188/0x24e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 __lock_acquire+0x106/0x7d10 kernel/locking/lockdep.c:4919 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162 finish_wait+0xb8/0x1d0 kernel/sched/wait.c:410 gfs2_quotad+0x4f3/0x680 fs/gfs2/quota.c:1579 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 17457: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384 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+0x134/0x1fb0 fs/gfs2/ops_fstype.c:1148 get_tree_bdev+0x3f1/0x610 fs/super.c:1366 gfs2_get_tree+0x4d/0x1e0 fs/gfs2/ops_fstype.c:1327 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 16512: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1729 [inline] slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3700 generic_shutdown_super+0x130/0x340 fs/super.c:501 kill_block_super+0x7c/0xe0 fs/super.c:1470 deactivate_locked_super+0x93/0xf0 fs/super.c:332 cleanup_mnt+0x42c/0x4b0 fs/namespace.c:1191 task_work_run+0x1d0/0x260 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88805b3cc000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 2992 bytes inside of 8192-byte region [ffff88805b3cc000, ffff88805b3ce000) The buggy address belongs to the physical page: page:ffffea00016cf200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5b3c8 head:ffffea00016cf200 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea00008f8800 dead000000000004 ffff888017442280 raw: 0000000000000000 0000000080020002 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 17029, tgid 17015 (syz.4.2992), ts 1027408292197, free_ts 1027377523684 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4328 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5614 alloc_slab_page+0x5d/0x160 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] ipv4_sysctl_init_net+0x25b/0x310 net/ipv4/sysctl_net_ipv4.c:1433 ops_init+0x355/0x5f0 net/core/net_namespace.c:138 setup_net+0x4f2/0xbd0 net/core/net_namespace.c:336 copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:508 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110 copy_namespaces+0x3b0/0x410 kernel/nsproxy.c:178 copy_process+0x19c2/0x4030 kernel/fork.c:2359 kernel_clone+0x24b/0x900 kernel/fork.c:2762 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1459 [inline] free_pcp_prepare mm/page_alloc.c:1509 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3383 anon_vma_chain_alloc mm/rmap.c:141 [inline] __anon_vma_prepare+0x64/0x420 mm/rmap.c:195 anon_vma_prepare include/linux/rmap.h:159 [inline] do_anonymous_page mm/memory.c:4187 [inline] handle_pte_fault mm/memory.c:5027 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x38ad/0x3ee0 mm/memory.c:5292 do_user_addr_fault+0x51f/0xb10 arch/x86/mm/fault.c:1340 handle_page_fault arch/x86/mm/fault.c:1431 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1487 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 Memory state around the buggy address: ffff88805b3cca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805b3ccb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805b3ccb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805b3ccc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805b3ccc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================