================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x106/0x7d10 kernel/locking/lockdep.c:4919 Read of size 8 at addr ffff888054cecbb0 by task gfs2_quotad/5463 CPU: 0 PID: 5463 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 5905: 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 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc+0xb0/0x240 mm/slab_common.c:949 kmalloc_array include/linux/slab.h:615 [inline] kcalloc include/linux/slab.h:646 [inline] snd_seq_oss_readq_new+0x7e/0x240 sound/core/seq/oss/seq_oss_readq.c:41 snd_seq_oss_open+0x7e4/0xf50 sound/core/seq/oss/seq_oss_init.c:231 odev_open+0x63/0x90 sound/core/seq/oss/seq_oss.c:128 chrdev_open+0x5c5/0x6a0 fs/char_dev.c:414 do_dentry_open+0x7e9/0x10d0 fs/open.c:882 do_open fs/namei.c:3634 [inline] path_openat+0x2635/0x2ee0 fs/namei.c:3791 do_filp_open+0x1f1/0x430 fs/namei.c:3818 do_sys_openat2+0x150/0x4b0 fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1347 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 5904: 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 snd_seq_oss_readq_delete+0x3a/0x50 sound/core/seq/oss/seq_oss_readq.c:65 free_devinfo+0x87/0xa0 sound/core/seq/oss/seq_oss_init.c:395 port_delete+0xc9/0x1a0 sound/core/seq/seq_ports.c:257 snd_seq_delete_port+0x1c0/0x200 sound/core/seq/seq_ports.c:286 snd_seq_ioctl_delete_port+0x8d/0x190 sound/core/seq/seq_clientmgr.c:1351 snd_seq_event_port_detach+0xe1/0x160 sound/core/seq/seq_ports.c:705 delete_port sound/core/seq/oss/seq_oss_init.c:340 [inline] snd_seq_oss_release+0x17b/0x310 sound/core/seq/oss/seq_oss_init.c:420 odev_release+0x52/0x70 sound/core/seq/oss/seq_oss.c:144 __fput+0x22c/0x920 fs/file_table.c:320 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 ffff888054cec000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 2992 bytes inside of 8192-byte region [ffff888054cec000, ffff888054cee000) The buggy address belongs to the physical page: page:ffffea0001533a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x54ce8 head:ffffea0001533a00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888017442280 raw: 0000000000000000 0000000000020002 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 0x1d28c0(GFP_NOWAIT|__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4754, tgid 4753 (syz.4.94), ts 99773625406, free_ts 99748079885 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 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc_node_track_caller+0x9e/0x230 mm/slab_common.c:956 kmalloc_reserve net/core/skbuff.c:446 [inline] __alloc_skb+0x22a/0x7e0 net/core/skbuff.c:515 alloc_skb include/linux/skbuff.h:1271 [inline] netlink_dump+0x1a5/0xd00 net/netlink/af_netlink.c:2196 netlink_recvmsg+0x68f/0xe00 net/netlink/af_netlink.c:1954 ____sys_recvmsg+0x2cb/0x5e0 net/socket.c:-1 ___sys_recvmsg+0x212/0x590 net/socket.c:2779 do_recvmmsg+0x393/0x870 net/socket.c:2873 __sys_recvmmsg net/socket.c:2954 [inline] __do_sys_recvmmsg net/socket.c:2975 [inline] __se_sys_recvmmsg net/socket.c:2968 [inline] __x64_sys_recvmmsg+0x1b4/0x250 net/socket.c:2968 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 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_slab mm/slub.c:2036 [inline] discard_slab mm/slub.c:2042 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2591 put_cpu_partial+0x17c/0x250 mm/slub.c:2667 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 ptlock_alloc mm/memory.c:6045 [inline] ptlock_init include/linux/mm.h:2480 [inline] pmd_ptlock_init include/linux/mm.h:2566 [inline] pgtable_pmd_page_ctor include/linux/mm.h:2602 [inline] pmd_alloc_one include/asm-generic/pgalloc.h:129 [inline] __pmd_alloc+0x116/0x760 mm/memory.c:5487 pmd_alloc include/linux/mm.h:2430 [inline] __handle_mm_fault mm/memory.c:5131 [inline] handle_mm_fault+0xa03/0x3ee0 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: ffff888054ceca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888054cecb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888054cecb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888054cecc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888054cecc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================