================================================================== BUG: KASAN: slab-use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:681 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0x6c2/0xcc0 kernel/locking/mutex.c:747 Read of size 8 at addr ffff88805daf40a0 by task khidpd_00065508/18682 CPU: 1 PID: 18682 Comm: khidpd_00065508 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline] __mutex_lock_common kernel/locking/mutex.c:681 [inline] __mutex_lock+0x6c2/0xcc0 kernel/locking/mutex.c:747 l2cap_unregister_user+0x6a/0x1a0 net/bluetooth/l2cap_core.c:1729 hidp_session_thread+0x3ec/0x430 net/bluetooth/hidp/core.c:1304 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Allocated by task 18308: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1007 [inline] __kmalloc+0xb4/0x230 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] hci_alloc_dev_priv+0x28/0x2060 net/bluetooth/hci_core.c:2441 hci_alloc_dev include/net/bluetooth/hci_core.h:1658 [inline] __vhci_create_device drivers/bluetooth/hci_vhci.c:421 [inline] vhci_create_device+0x11b/0x650 drivers/bluetooth/hci_vhci.c:480 vhci_get_user drivers/bluetooth/hci_vhci.c:537 [inline] vhci_write+0x3b5/0x470 drivers/bluetooth/hci_vhci.c:617 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x46c/0x990 fs/read_write.c:584 ksys_write+0x150/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 18308: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] __kmem_cache_free+0xba/0x1e0 mm/slub.c:3843 bt_host_release+0x82/0x90 net/bluetooth/hci_sysfs.c:87 device_release+0x96/0x1c0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x221/0x460 lib/kobject.c:737 vhci_release+0x15d/0x1a0 drivers/bluetooth/hci_vhci.c:692 __fput+0x234/0x970 fs/file_table.c:384 task_work_run+0x1d4/0x260 kernel/task_work.c:245 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x95a/0x2460 kernel/exit.c:883 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 __do_sys_exit_group kernel/exit.c:1035 [inline] __se_sys_exit_group kernel/exit.c:1033 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1033 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 insert_work+0x3d/0x310 kernel/workqueue.c:1670 __queue_work+0xc39/0x1020 kernel/workqueue.c:1819 queue_work_on+0x128/0x1f0 kernel/workqueue.c:1854 l2cap_chan_send+0x3c9/0x25b0 net/bluetooth/l2cap_core.c:-1 l2cap_sock_sendmsg+0x1ae/0x2c0 net/bluetooth/l2cap_sock.c:1134 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_sendmsg+0x25a/0x3d0 net/socket.c:768 hidp_send_frame net/bluetooth/hidp/core.c:627 [inline] hidp_process_transmit+0x1c6/0x400 net/bluetooth/hidp/core.c:641 hidp_session_run+0x1385/0x1480 net/bluetooth/hidp/core.c:1234 hidp_session_thread+0x2cc/0x430 net/bluetooth/hidp/core.c:1288 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Second to last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 insert_work+0x3d/0x310 kernel/workqueue.c:1670 __queue_work+0xc39/0x1020 kernel/workqueue.c:1819 queue_work_on+0x128/0x1f0 kernel/workqueue.c:1854 l2cap_chan_send+0x3c9/0x25b0 net/bluetooth/l2cap_core.c:-1 l2cap_sock_sendmsg+0x1ae/0x2c0 net/bluetooth/l2cap_sock.c:1134 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_sendmsg+0x25a/0x3d0 net/socket.c:768 hidp_send_frame net/bluetooth/hidp/core.c:627 [inline] hidp_process_transmit+0x1c6/0x400 net/bluetooth/hidp/core.c:641 hidp_session_run+0x1385/0x1480 net/bluetooth/hidp/core.c:1234 hidp_session_thread+0x2cc/0x430 net/bluetooth/hidp/core.c:1288 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff88805daf4000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 160 bytes inside of freed 8192-byte region [ffff88805daf4000, ffff88805daf6000) The buggy address belongs to the physical page: page:ffffea000176bc00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5daf0 head:ffffea000176bc00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017c42280 ffffea0001e7d400 dead000000000005 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5777, tgid 5777 (syz-executor), ts 84499418606, free_ts 27414167334 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581 prep_new_page mm/page_alloc.c:1588 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4500 alloc_slab_page+0x5d/0x160 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5d/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x19e/0x250 mm/slub.c:3534 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] macvlan_port_create drivers/net/macvlan.c:1260 [inline] macvlan_common_newlink+0x523/0x19d0 drivers/net/macvlan.c:1495 rtnl_newlink_create net/core/rtnetlink.c:3517 [inline] __rtnl_newlink net/core/rtnetlink.c:3737 [inline] rtnl_newlink+0x1542/0x20a0 net/core/rtnetlink.c:3750 rtnetlink_rcv_msg+0x869/0xfa0 net/core/rtnetlink.c:6472 netlink_rcv_skb+0x241/0x4d0 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x4a9/0x6b0 net/socket.c:2200 __do_sys_sendto net/socket.c:2212 [inline] __se_sys_sendto net/socket.c:2208 [inline] __x64_sys_sendto+0xde/0xf0 net/socket.c:2208 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458 free_contig_range+0xa1/0x150 mm/page_alloc.c:6420 destroy_args+0x80/0x850 mm/debug_vm_pgtable.c:1015 debug_vm_pgtable+0x411/0x440 mm/debug_vm_pgtable.c:1400 do_one_initcall+0x242/0x790 init/main.c:1250 do_initcall_level+0x137/0x1f0 init/main.c:1312 do_initcalls+0x69/0xd0 init/main.c:1328 kernel_init_freeable+0x3ed/0x580 init/main.c:1565 kernel_init+0x1d/0x1c0 init/main.c:1455 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Memory state around the buggy address: ffff88805daf3f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805daf4000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805daf4080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805daf4100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805daf4180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================