Extracting prog: 2m23.980094576s
Minimizing prog: 11m24.657810772s
Simplifying prog options: 0s
Extracting C: 35.317340622s
Simplifying C: 20m38.212962405s


extracting reproducer from 28 programs
testing a last program of every proc
single: executing 5 programs separately with timeout 30s
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci-syz_emit_vhci
detailed listing:
executing program 0:
r0 = syz_init_net_socket$bt_sco(0x1f, 0x5, 0x2)
connect$bt_sco(r0, &(0x7f0000000100), 0x8)
syz_emit_vhci(&(0x7f0000000140)=ANY=[@ANYBLOB="042c"], 0x14)
syz_emit_vhci(&(0x7f0000000140)=ANY=[], 0x14)

program crashed: possible deadlock in sco_connect_cfm
single: successfully extracted reproducer
found reproducer with 4 syscalls
minimizing guilty program
testing program (duration=52.378864651s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
detailed listing:
executing program 0:
r0 = syz_init_net_socket$bt_sco(0x1f, 0x5, 0x2)
connect$bt_sco(r0, &(0x7f0000000100), 0x8)
syz_emit_vhci(&(0x7f0000000140)=ANY=[@ANYBLOB="042c"], 0x14)

program crashed: possible deadlock in sco_connect_cfm
testing program (duration=52.378864651s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco
detailed listing:
executing program 0:
r0 = syz_init_net_socket$bt_sco(0x1f, 0x5, 0x2)
connect$bt_sco(r0, &(0x7f0000000100), 0x8)

program did not crash
testing program (duration=52.378864651s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-syz_emit_vhci
detailed listing:
executing program 0:
syz_init_net_socket$bt_sco(0x1f, 0x5, 0x2)
syz_emit_vhci(&(0x7f0000000140)=ANY=[@ANYBLOB="042c"], 0x14)

program did not crash
testing program (duration=52.378864651s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): connect$bt_sco-syz_emit_vhci
detailed listing:
executing program 0:
connect$bt_sco(0xffffffffffffffff, &(0x7f0000000100), 0x8)
syz_emit_vhci(&(0x7f0000000140)=ANY=[@ANYBLOB="042c"], 0x14)

program did not crash
testing program (duration=52.378864651s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
detailed listing:
executing program 0:
r0 = syz_init_net_socket$bt_sco(0x1f, 0x5, 0x2)
connect$bt_sco(r0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000140)=ANY=[@ANYBLOB="042c"], 0x14)

program did not crash
testing program (duration=52.378864651s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
detailed listing:
executing program 0:
r0 = syz_init_net_socket$bt_sco(0x1f, 0x5, 0x2)
connect$bt_sco(r0, &(0x7f0000000100), 0x8)
syz_emit_vhci(0x0, 0x14)

program did not crash
testing program (duration=52.378864651s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
detailed listing:
executing program 0:
r0 = syz_init_net_socket$bt_sco(0x1f, 0x5, 0x2)
connect$bt_sco(r0, &(0x7f0000000100), 0x8)
syz_emit_vhci(&(0x7f0000000140)=ANY=[@ANYBLOB], 0x14)

program did not crash
extracting C reproducer
testing compiled C program (duration=52.378864651s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program crashed: possible deadlock in sco_connect_cfm
simplifying C reproducer
testing compiled C program (duration=52.378864651s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program crashed: possible deadlock in sco_connect_cfm
testing compiled C program (duration=52.378864651s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program crashed: possible deadlock in sco_connect_cfm
testing compiled C program (duration=52.378864651s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program did not crash
testing compiled C program (duration=52.378864651s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program crashed: possible deadlock in hci_conn_hash_flush
a never seen crash title: possible deadlock in hci_conn_hash_flush, ignore
testing compiled C program (duration=52.378864651s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:false NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program did not crash
testing compiled C program (duration=52.378864651s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program did not crash
testing compiled C program (duration=52.378864651s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program crashed: possible deadlock in sco_connect_cfm
testing compiled C program (duration=52.378864651s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program crashed: possible deadlock in sco_connect_cfm
testing compiled C program (duration=52.378864651s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program did not crash
testing compiled C program (duration=52.378864651s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program crashed: possible deadlock in sco_connect_cfm
testing compiled C program (duration=52.378864651s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program crashed: possible deadlock in sco_connect_cfm
testing compiled C program (duration=52.378864651s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:false HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program crashed: possible deadlock in sco_connect_cfm
testing compiled C program (duration=52.378864651s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:false HandleSegv:false Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program crashed: possible deadlock in sco_connect_cfm
testing compiled C program (duration=52.378864651s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false IEEE802154:false Sysctl:false Swap:true UseTmpDir:false HandleSegv:false Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program crashed: possible deadlock in sco_connect_cfm
testing compiled C program (duration=52.378864651s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$bt_sco-connect$bt_sco-syz_emit_vhci
program crashed: possible deadlock in sco_connect_cfm
reproducing took 35m2.168239824s
repro crashed as (corrupted=false):
======================================================
WARNING: possible circular locking dependency detected
5.15.178-syzkaller #0 Not tainted
------------------------------------------------------
kworker/u5:2/4023 is trying to acquire lock:
ffff0000ce600120 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1684 [inline]
ffff0000ce600120 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at: sco_conn_ready net/bluetooth/sco.c:1107 [inline]
ffff0000ce600120 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at: sco_connect_cfm+0x140/0x908 net/bluetooth/sco.c:1198

but task is already holding lock:
ffff800016df9988 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:1502 [inline]
ffff800016df9988 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_sync_conn_complete_evt+0x404/0x8c0 net/bluetooth/hci_event.c:4551

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (hci_cb_list_lock){+.+.}-{3:3}:
       __mutex_lock_common+0x194/0x2154 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
       hci_connect_cfm include/net/bluetooth/hci_core.h:1502 [inline]
       hci_remote_features_evt+0x444/0x904 net/bluetooth/hci_event.c:3352
       hci_event_packet+0x5ec/0x12b4 net/bluetooth/hci_event.c:6421
       hci_rx_work+0x1d0/0x830 net/bluetooth/hci_core.c:5160
       process_one_work+0x790/0x11b8 kernel/workqueue.c:2310
       worker_thread+0x910/0x1034 kernel/workqueue.c:2457
       kthread+0x37c/0x45c kernel/kthread.c:334
       ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870

-> #1 (&hdev->lock){+.+.}-{3:3}:
       __mutex_lock_common+0x194/0x2154 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
       sco_sock_connect+0x170/0x848 net/bluetooth/sco.c:591
       __sys_connect_file net/socket.c:1923 [inline]
       __sys_connect+0x268/0x290 net/socket.c:1940
       __do_sys_connect net/socket.c:1950 [inline]
       __se_sys_connect net/socket.c:1947 [inline]
       __arm64_sys_connect+0x7c/0x94 net/socket.c:1947
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
       el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
       el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #0 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain kernel/locking/lockdep.c:3788 [inline]
       __lock_acquire+0x32d4/0x7638 kernel/locking/lockdep.c:5012
       lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623
       lock_sock_nested+0xec/0x1ec net/core/sock.c:3253
       lock_sock include/net/sock.h:1684 [inline]
       sco_conn_ready net/bluetooth/sco.c:1107 [inline]
       sco_connect_cfm+0x140/0x908 net/bluetooth/sco.c:1198
       hci_connect_cfm include/net/bluetooth/hci_core.h:1505 [inline]
       hci_sync_conn_complete_evt+0x468/0x8c0 net/bluetooth/hci_event.c:4551
       hci_event_packet+0x8e0/0x12b4 net/bluetooth/hci_event.c:6483
       hci_rx_work+0x1d0/0x830 net/bluetooth/hci_core.c:5160
       process_one_work+0x790/0x11b8 kernel/workqueue.c:2310
       worker_thread+0x910/0x1034 kernel/workqueue.c:2457
       kthread+0x37c/0x45c kernel/kthread.c:334
       ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870

other info that might help us debug this:

Chain exists of:
  sk_lock-AF_BLUETOOTH-BTPROTO_SCO --> &hdev->lock --> hci_cb_list_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(hci_cb_list_lock);
                               lock(&hdev->lock);
                               lock(hci_cb_list_lock);
  lock(sk_lock-AF_BLUETOOTH-BTPROTO_SCO);

 *** DEADLOCK ***

4 locks held by kworker/u5:2/4023:
 #0: ffff0000cac39938 ((wq_completion)hci0#2){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff80001dd77c00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff0000c9618078 (&hdev->lock){+.+.}-{3:3}, at: hci_sync_conn_complete_evt+0xb4/0x8c0 net/bluetooth/hci_event.c:4471
 #3: ffff800016df9988 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:1502 [inline]
 #3: ffff800016df9988 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_sync_conn_complete_evt+0x404/0x8c0 net/bluetooth/hci_event.c:4551

stack backtrace:
CPU: 1 PID: 4023 Comm: kworker/u5:2 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Workqueue: hci0 hci_rx_work
Call trace:
 dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2011
 check_noncircular+0x2cc/0x378 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain kernel/locking/lockdep.c:3788 [inline]
 __lock_acquire+0x32d4/0x7638 kernel/locking/lockdep.c:5012
 lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623
 lock_sock_nested+0xec/0x1ec net/core/sock.c:3253
 lock_sock include/net/sock.h:1684 [inline]
 sco_conn_ready net/bluetooth/sco.c:1107 [inline]
 sco_connect_cfm+0x140/0x908 net/bluetooth/sco.c:1198
 hci_connect_cfm include/net/bluetooth/hci_core.h:1505 [inline]
 hci_sync_conn_complete_evt+0x468/0x8c0 net/bluetooth/hci_event.c:4551
 hci_event_packet+0x8e0/0x12b4 net/bluetooth/hci_event.c:6483
 hci_rx_work+0x1d0/0x830 net/bluetooth/hci_core.c:5160
 process_one_work+0x790/0x11b8 kernel/workqueue.c:2310
 worker_thread+0x910/0x1034 kernel/workqueue.c:2457
 kthread+0x37c/0x45c kernel/kthread.c:334
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870

final repro crashed as (corrupted=false):
======================================================
WARNING: possible circular locking dependency detected
5.15.178-syzkaller #0 Not tainted
------------------------------------------------------
kworker/u5:2/4023 is trying to acquire lock:
ffff0000ce600120 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1684 [inline]
ffff0000ce600120 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at: sco_conn_ready net/bluetooth/sco.c:1107 [inline]
ffff0000ce600120 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at: sco_connect_cfm+0x140/0x908 net/bluetooth/sco.c:1198

but task is already holding lock:
ffff800016df9988 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:1502 [inline]
ffff800016df9988 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_sync_conn_complete_evt+0x404/0x8c0 net/bluetooth/hci_event.c:4551

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (hci_cb_list_lock){+.+.}-{3:3}:
       __mutex_lock_common+0x194/0x2154 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
       hci_connect_cfm include/net/bluetooth/hci_core.h:1502 [inline]
       hci_remote_features_evt+0x444/0x904 net/bluetooth/hci_event.c:3352
       hci_event_packet+0x5ec/0x12b4 net/bluetooth/hci_event.c:6421
       hci_rx_work+0x1d0/0x830 net/bluetooth/hci_core.c:5160
       process_one_work+0x790/0x11b8 kernel/workqueue.c:2310
       worker_thread+0x910/0x1034 kernel/workqueue.c:2457
       kthread+0x37c/0x45c kernel/kthread.c:334
       ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870

-> #1 (&hdev->lock){+.+.}-{3:3}:
       __mutex_lock_common+0x194/0x2154 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
       sco_sock_connect+0x170/0x848 net/bluetooth/sco.c:591
       __sys_connect_file net/socket.c:1923 [inline]
       __sys_connect+0x268/0x290 net/socket.c:1940
       __do_sys_connect net/socket.c:1950 [inline]
       __se_sys_connect net/socket.c:1947 [inline]
       __arm64_sys_connect+0x7c/0x94 net/socket.c:1947
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
       el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
       el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #0 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain kernel/locking/lockdep.c:3788 [inline]
       __lock_acquire+0x32d4/0x7638 kernel/locking/lockdep.c:5012
       lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623
       lock_sock_nested+0xec/0x1ec net/core/sock.c:3253
       lock_sock include/net/sock.h:1684 [inline]
       sco_conn_ready net/bluetooth/sco.c:1107 [inline]
       sco_connect_cfm+0x140/0x908 net/bluetooth/sco.c:1198
       hci_connect_cfm include/net/bluetooth/hci_core.h:1505 [inline]
       hci_sync_conn_complete_evt+0x468/0x8c0 net/bluetooth/hci_event.c:4551
       hci_event_packet+0x8e0/0x12b4 net/bluetooth/hci_event.c:6483
       hci_rx_work+0x1d0/0x830 net/bluetooth/hci_core.c:5160
       process_one_work+0x790/0x11b8 kernel/workqueue.c:2310
       worker_thread+0x910/0x1034 kernel/workqueue.c:2457
       kthread+0x37c/0x45c kernel/kthread.c:334
       ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870

other info that might help us debug this:

Chain exists of:
  sk_lock-AF_BLUETOOTH-BTPROTO_SCO --> &hdev->lock --> hci_cb_list_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(hci_cb_list_lock);
                               lock(&hdev->lock);
                               lock(hci_cb_list_lock);
  lock(sk_lock-AF_BLUETOOTH-BTPROTO_SCO);

 *** DEADLOCK ***

4 locks held by kworker/u5:2/4023:
 #0: ffff0000cac39938 ((wq_completion)hci0#2){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff80001dd77c00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff0000c9618078 (&hdev->lock){+.+.}-{3:3}, at: hci_sync_conn_complete_evt+0xb4/0x8c0 net/bluetooth/hci_event.c:4471
 #3: ffff800016df9988 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:1502 [inline]
 #3: ffff800016df9988 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_sync_conn_complete_evt+0x404/0x8c0 net/bluetooth/hci_event.c:4551

stack backtrace:
CPU: 1 PID: 4023 Comm: kworker/u5:2 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Workqueue: hci0 hci_rx_work
Call trace:
 dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2011
 check_noncircular+0x2cc/0x378 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain kernel/locking/lockdep.c:3788 [inline]
 __lock_acquire+0x32d4/0x7638 kernel/locking/lockdep.c:5012
 lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623
 lock_sock_nested+0xec/0x1ec net/core/sock.c:3253
 lock_sock include/net/sock.h:1684 [inline]
 sco_conn_ready net/bluetooth/sco.c:1107 [inline]
 sco_connect_cfm+0x140/0x908 net/bluetooth/sco.c:1198
 hci_connect_cfm include/net/bluetooth/hci_core.h:1505 [inline]
 hci_sync_conn_complete_evt+0x468/0x8c0 net/bluetooth/hci_event.c:4551
 hci_event_packet+0x8e0/0x12b4 net/bluetooth/hci_event.c:6483
 hci_rx_work+0x1d0/0x830 net/bluetooth/hci_core.c:5160
 process_one_work+0x790/0x11b8 kernel/workqueue.c:2310
 worker_thread+0x910/0x1034 kernel/workqueue.c:2457
 kthread+0x37c/0x45c kernel/kthread.c:334
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870