Bluetooth: hci4: Controller not accepting commands anymore: ncmd = 0 Bluetooth: hci4: Injecting HCI hardware error event Bluetooth: hci4: hardware error 0x00 ================================================================== BUG: KASAN: slab-use-after-free in __raw_spin_lock_bh include/linux/spinlock_api_smp.h:150 [inline] BUG: KASAN: slab-use-after-free in _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:182 Read of size 1 at addr ffff888079cda5a0 by task kworker/u9:0/50 CPU: 1 UID: 0 PID: 50 Comm: kworker/u9:0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Workqueue: hci4 hci_error_reset Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 __kasan_check_byte+0x36/0x50 mm/kasan/common.c:574 kasan_check_byte include/linux/kasan.h:402 [inline] lock_acquire kernel/locking/lockdep.c:5842 [inline] lock_acquire+0x132/0x370 kernel/locking/lockdep.c:5825 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:150 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:182 spin_lock_bh include/linux/spinlock.h:348 [inline] bt_accept_unlink+0x64/0x370 net/bluetooth/af_bluetooth.c:262 l2cap_sock_teardown_cb+0x1a3/0x3f0 net/bluetooth/l2cap_sock.c:1710 l2cap_chan_del+0xa6/0x920 net/bluetooth/l2cap_core.c:687 l2cap_conn_del+0x34f/0x6b0 net/bluetooth/l2cap_core.c:1825 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7601 [inline] l2cap_disconn_cfm+0x9f/0x100 net/bluetooth/l2cap_core.c:7594 hci_disconn_cfm include/net/bluetooth/hci_core.h:2154 [inline] hci_conn_hash_flush+0x10e/0x280 net/bluetooth/hci_conn.c:2735 hci_dev_close_sync+0x5cf/0x13c0 net/bluetooth/hci_sync.c:5513 hci_dev_do_close+0x2e/0xb0 net/bluetooth/hci_core.c:499 hci_error_reset+0xbf/0x380 net/bluetooth/hci_core.c:995 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322 process_scheduled_works kernel/workqueue.c:3405 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 15808: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5334 [inline] __kmalloc_noprof+0x322/0x820 mm/slub.c:5359 _kmalloc_noprof include/linux/slab.h:992 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] tls_get_rec net/tls/tls_sw.c:366 [inline] tls_sw_sendmsg_locked net/tls/tls_sw.c:811 [inline] tls_sw_sendmsg+0x11ee/0x2e00 net/tls/tls_sw.c:1022 inet6_sendmsg+0x11c/0x140 net/ipv6/af_inet6.c:641 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] sock_write_iter+0x41a/0x5b0 net/socket.c:1241 do_iter_readv_writev+0x6f7/0x930 fs/read_write.c:828 vfs_writev+0x360/0xdd0 fs/read_write.c:1058 do_writev+0x28a/0x340 fs/read_write.c:1104 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 15808: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2677 [inline] slab_free mm/slub.c:6377 [inline] kfree+0x22b/0x6c0 mm/slub.c:6692 tls_tx_records+0x46f/0x720 net/tls/tls_sw.c:454 tls_sw_sendmsg_locked net/tls/tls_sw.c:962 [inline] tls_sw_sendmsg+0x10fc/0x2e00 net/tls/tls_sw.c:1022 inet6_sendmsg+0x11c/0x140 net/ipv6/af_inet6.c:641 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] sock_write_iter+0x41a/0x5b0 net/socket.c:1241 do_iter_readv_writev+0x6f7/0x930 fs/read_write.c:828 vfs_writev+0x360/0xdd0 fs/read_write.c:1058 do_writev+0x28a/0x340 fs/read_write.c:1104 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888079cda000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1440 bytes inside of freed 2048-byte region [ffff888079cda000, ffff888079cda800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x79cd8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88813fe22000 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800080008 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813fe22000 dead000000000100 dead000000000122 head: 0000000000000000 0000000800080008 00000000f5000000 0000000000000000 head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5257, tgid 5257 (dhcpcd), ts 67170987807, free_ts 67138758709 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304 alloc_slab_page mm/slub.c:3266 [inline] allocate_slab mm/slub.c:3380 [inline] new_slab+0xa2/0x640 mm/slub.c:3426 refill_objects+0xe3/0x410 mm/slub.c:7310 refill_sheaf mm/slub.c:2804 [inline] __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4675 alloc_from_pcs mm/slub.c:4773 [inline] slab_alloc_node mm/slub.c:4905 [inline] __do_kmalloc_node mm/slub.c:5333 [inline] __kmalloc_node_track_caller_noprof+0x679/0x830 mm/slub.c:5471 kmalloc_reserve+0xe8/0x350 net/core/skbuff.c:637 pskb_expand_head+0x249/0x10e0 net/core/skbuff.c:2312 netlink_trim+0x22d/0x2f0 net/netlink/af_netlink.c:1300 netlink_broadcast_filtered+0x6d/0xf20 net/netlink/af_netlink.c:1518 nlmsg_multicast_filtered include/net/netlink.h:1165 [inline] nlmsg_multicast include/net/netlink.h:1184 [inline] nlmsg_notify+0xb1/0x290 net/netlink/af_netlink.c:2599 rtnl_notify net/core/rtnetlink.c:963 [inline] rtmsg_ifinfo_send net/core/rtnetlink.c:4553 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:4569 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:4556 [inline] rtmsg_ifinfo+0x177/0x1b0 net/core/rtnetlink.c:4575 __dev_notify_flags+0x24c/0x2e0 net/core/dev.c:9795 netif_change_flags+0x108/0x160 net/core/dev.c:9828 dev_change_flags+0xba/0x260 net/core/dev_api.c:68 page last free pid 4951 tgid 4951 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4584 [inline] slab_alloc_node mm/slub.c:4917 [inline] kmem_cache_alloc_node_noprof+0x27d/0x6b0 mm/slub.c:4989 __alloc_skb+0x140/0x710 net/core/skbuff.c:704 alloc_skb include/linux/skbuff.h:1384 [inline] alloc_skb_with_frags+0xdd/0x760 net/core/skbuff.c:6775 sock_alloc_send_pskb+0x801/0x980 net/core/sock.c:3012 unix_dgram_sendmsg+0x3c7/0x1810 net/unix/af_unix.c:2137 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] __sys_sendto+0x48b/0x4e0 net/socket.c:2252 __do_sys_sendto net/socket.c:2259 [inline] __se_sys_sendto net/socket.c:2255 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2255 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888079cda480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888079cda500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888079cda580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888079cda600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888079cda680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================