Bluetooth: hci1: Opcode 0x0c1a failed: -4 Bluetooth: hci1: Error when powering off device on rfkill (-4) ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 1 PID: 20361 at lib/refcount.c:28 refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28 Modules linked in: CPU: 1 UID: 0 PID: 20361 Comm: syz.3.3524 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28 Code: ff 89 de e8 28 c9 13 fd 84 db 0f 85 66 ff ff ff e8 3b ce 13 fd c6 05 89 de c3 0b 01 90 48 c7 c7 e0 22 f1 8b e8 87 56 d2 fc 90 <0f> 0b 90 90 e9 43 ff ff ff e8 18 ce 13 fd 0f b6 1d 64 de c3 0b 31 RSP: 0018:ffffc9000641f8a8 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffc90007981000 RDX: 0000000000080000 RSI: ffffffff817a5e65 RDI: 0000000000000001 RBP: ffff888027d2d478 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff888061cd3800 R13: ffff888027d2d478 R14: ffffffff85ddf360 R15: ffffffff90669ee0 FS: 0000000000000000(0000) GS:ffff8880978e7000(0063) knlGS:00000000f54a6b40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 000000005850d4c0 CR3: 000000005ae24000 CR4: 0000000000352ef0 DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: __refcount_sub_and_test include/linux/refcount.h:400 [inline] __refcount_dec_and_test include/linux/refcount.h:432 [inline] refcount_dec_and_test include/linux/refcount.h:450 [inline] kref_put include/linux/kref.h:64 [inline] klist_dec_and_del lib/klist.c:206 [inline] klist_put+0x11b/0x1b0 lib/klist.c:217 klist_del lib/klist.c:230 [inline] klist_remove+0x13f/0x2e0 lib/klist.c:249 device_move+0x12d/0x10d0 drivers/base/core.c:4615 hci_conn_del_sysfs+0x81/0x180 net/bluetooth/hci_sysfs.c:75 hci_conn_cleanup net/bluetooth/hci_conn.c:173 [inline] hci_conn_del+0x657/0x1180 net/bluetooth/hci_conn.c:1210 hci_conn_hash_flush+0x186/0x260 net/bluetooth/hci_conn.c:2603 hci_dev_close_sync+0x602/0x11d0 net/bluetooth/hci_sync.c:5303 hci_dev_do_close+0x2e/0x90 net/bluetooth/hci_core.c:501 hci_rfkill_set_block+0x225/0x360 net/bluetooth/hci_core.c:929 rfkill_set_block+0x1fe/0x550 net/rfkill/core.c:346 rfkill_fop_write+0x2c0/0x580 net/rfkill/core.c:1301 vfs_write+0x2a0/0x11d0 fs/read_write.c:684 ksys_write+0x1f8/0x250 fs/read_write.c:738 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x7c/0x300 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7fb1579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f54a655c EFLAGS: 00000296 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000080000300 RDX: 0000000000000008 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi