================================================================== BUG: KASAN: use-after-free in __lock_acquire+0xf7/0x7c50 kernel/locking/lockdep.c:4919 Read of size 8 at addr ffff88805941cbb0 by task gfs2_quotad/12905 CPU: 1 PID: 12905 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+0x168/0x22e 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+0xf7/0x7c50 kernel/locking/lockdep.c:4919 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162 finish_wait+0xb8/0x1d0 kernel/sched/wait.c:410 gfs2_quotad+0x4e6/0x670 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 12900: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:383 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+0x117/0x1f80 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+0x2d6/0x3c0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88805941c000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 2992 bytes inside of 8192-byte region [ffff88805941c000, ffff88805941e000) The buggy address belongs to the physical page: page:ffffea0001650600 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88805941c000 pfn:0x59418 head:ffffea0001650600 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffff888017440ac8 ffffea0001f12608 ffff888017442280 raw: ffff88805941c000 0000000000020001 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4274, tgid 4274 (syz-executor), ts 74428112214, free_ts 22749805905 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+0x1a26/0x1ac0 mm/page_alloc.c:4328 __alloc_pages+0x1df/0x4e0 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+0xbc6/0x1230 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 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc_node+0xa0/0x240 mm/slab_common.c:943 kmalloc_node include/linux/slab.h:589 [inline] kvmalloc_node+0x6c/0x180 mm/util.c:581 kvmalloc include/linux/slab.h:716 [inline] kvmalloc_array include/linux/slab.h:734 [inline] __ptr_ring_init_queue_alloc include/linux/ptr_ring.h:471 [inline] ptr_ring_resize include/linux/ptr_ring.h:594 [inline] tun_attach+0x884/0x1570 drivers/net/tun.c:791 tun_net_init+0x3d5/0x4e0 drivers/net/tun.c:1007 register_netdevice+0x65b/0x1aa0 net/core/dev.c:10130 tun_set_iff+0x848/0xed0 drivers/net/tun.c:2851 __tun_chr_ioctl+0x730/0x1e10 drivers/net/tun.c:3114 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 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 free_contig_range+0x9d/0x150 mm/page_alloc.c:9574 destroy_args+0x100/0xa31 mm/debug_vm_pgtable.c:1031 debug_vm_pgtable+0x32a/0x37e mm/debug_vm_pgtable.c:1359 do_one_initcall+0x214/0x7a0 init/main.c:1310 do_initcall_level+0x137/0x1e4 init/main.c:1383 do_initcalls+0x4b/0x8a init/main.c:1399 kernel_init_freeable+0x3fa/0x5ac init/main.c:1638 kernel_init+0x19/0x1b0 init/main.c:1526 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff88805941ca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805941cb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805941cb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805941cc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805941cc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================