Extracting prog: 1m45.031934477s
Minimizing prog: 27.689µs
Simplifying prog options: 5m19.194176706s
Extracting C: 1m46.704280788s
Simplifying C: 0s
extracting reproducer from 1 programs
testing a last program of every proc
single: executing 1 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}}): socket$inet
detailed listing:
executing program 0:
socket$inet(0x2, 0x4000000000000001, 0x0)
program crashed: possible deadlock in lapbeth_device_event
single: successfully extracted reproducer
found reproducer with 1 syscalls
minimizing guilty program
extracting C reproducer
testing compiled C program (duration=50.045503641s, {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}}): socket$inet
program did not crash
simplifying guilty program options
testing program (duration=50.045503641s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet
detailed listing:
executing program 0:
socket$inet(0x2, 0x4000000000000001, 0x0)
program crashed: possible deadlock in lapbeth_device_event
extracting C reproducer
testing compiled C program (duration=50.045503641s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet
program did not crash
testing program (duration=50.045503641s, {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}}): socket$inet
detailed listing:
executing program 0:
socket$inet(0x2, 0x4000000000000001, 0x0)
program crashed: possible deadlock in lapbeth_device_event
extracting C reproducer
testing compiled C program (duration=50.045503641s, {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}}): socket$inet
program did not crash
reproducing took 8m32.015523688s
repro crashed as (corrupted=false):
============================================
WARNING: possible recursive locking detected
6.14.0-rc5-syzkaller-01152-g48c57a49c50a #0 Not tainted
--------------------------------------------
dhcpcd/5502 is trying to acquire lock:
ffff888029c9cd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2731 [inline]
ffff888029c9cd28 (&dev->lock){+.+.}-{4:4}, at: netif_napi_add_weight include/linux/netdevice.h:2763 [inline]
ffff888029c9cd28 (&dev->lock){+.+.}-{4:4}, at: lapbeth_new_device drivers/net/wan/lapbether.c:415 [inline]
ffff888029c9cd28 (&dev->lock){+.+.}-{4:4}, at: lapbeth_device_event+0x766/0xa20 drivers/net/wan/lapbether.c:460
but task is already holding lock:
ffff88805d49cd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2731 [inline]
ffff88805d49cd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:40 [inline]
ffff88805d49cd28 (&dev->lock){+.+.}-{4:4}, at: dev_change_flags+0x120/0x270 net/core/dev_api.c:67
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&dev->lock);
lock(&dev->lock);
*** DEADLOCK ***
May be due to missing lock nesting notation
2 locks held by dhcpcd/5502:
#0: ffffffff8fed6908 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8fed6908 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x34c/0x1d80 net/ipv4/devinet.c:1121
#1: ffff88805d49cd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2731 [inline]
#1: ffff88805d49cd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:40 [inline]
#1: ffff88805d49cd28 (&dev->lock){+.+.}-{4:4}, at: dev_change_flags+0x120/0x270 net/core/dev_api.c:67
stack backtrace:
CPU: 0 UID: 0 PID: 5502 Comm: dhcpcd Not tainted 6.14.0-rc5-syzkaller-01152-g48c57a49c50a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
print_deadlock_bug+0x483/0x620 kernel/locking/lockdep.c:3039
check_deadlock kernel/locking/lockdep.c:3091 [inline]
validate_chain+0x15e2/0x5920 kernel/locking/lockdep.c:3893
__lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730
netdev_lock include/linux/netdevice.h:2731 [inline]
netif_napi_add_weight include/linux/netdevice.h:2763 [inline]
lapbeth_new_device drivers/net/wan/lapbether.c:415 [inline]
lapbeth_device_event+0x766/0xa20 drivers/net/wan/lapbether.c:460
notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85
__dev_notify_flags+0x207/0x400
netif_change_flags+0xf0/0x1a0 net/core/dev.c:9443
dev_change_flags+0x146/0x270 net/core/dev_api.c:68
devinet_ioctl+0xea2/0x1d80 net/ipv4/devinet.c:1200
inet_ioctl+0x3d7/0x4f0 net/ipv4/af_inet.c:1001
sock_do_ioctl+0x158/0x460 net/socket.c:1190
sock_ioctl+0x626/0x8e0 net/socket.c:1309
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:906 [inline]
__se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa6ff44ed49
Code: 5c c3 48 8d 44 24 08 48 89 54 24 e0 48 89 44 24 c0 48 8d 44 24 d0 48 89 44 24 c8 b8 10 00 00 00 c7 44 24 b8 10 00 00 00 0f 05 <41> 89 c0 3d 00 f0 ff ff 76 10 48 8b 15 ae 60 0d 00 f7 d8 41 83 c8
RSP: 002b:00007ffdbfdc91f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa6ff3806c0 RCX: 00007fa6ff44ed49
RDX: 00007ffdbfdd93e8 RSI: 0000000000008914 RDI: 0000000000000018
RBP: 00007ffdbfde95a8 R08: 00007ffdbfdd93a8 R09: 00007ffdbfdd9358
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffdbfdd93e8 R14: 0000000000000028 R15: 0000000000008914
final repro crashed as (corrupted=false):
============================================
WARNING: possible recursive locking detected
6.14.0-rc5-syzkaller-01152-g48c57a49c50a #0 Not tainted
--------------------------------------------
dhcpcd/5502 is trying to acquire lock:
ffff888029c9cd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2731 [inline]
ffff888029c9cd28 (&dev->lock){+.+.}-{4:4}, at: netif_napi_add_weight include/linux/netdevice.h:2763 [inline]
ffff888029c9cd28 (&dev->lock){+.+.}-{4:4}, at: lapbeth_new_device drivers/net/wan/lapbether.c:415 [inline]
ffff888029c9cd28 (&dev->lock){+.+.}-{4:4}, at: lapbeth_device_event+0x766/0xa20 drivers/net/wan/lapbether.c:460
but task is already holding lock:
ffff88805d49cd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2731 [inline]
ffff88805d49cd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:40 [inline]
ffff88805d49cd28 (&dev->lock){+.+.}-{4:4}, at: dev_change_flags+0x120/0x270 net/core/dev_api.c:67
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&dev->lock);
lock(&dev->lock);
*** DEADLOCK ***
May be due to missing lock nesting notation
2 locks held by dhcpcd/5502:
#0: ffffffff8fed6908 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8fed6908 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x34c/0x1d80 net/ipv4/devinet.c:1121
#1: ffff88805d49cd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2731 [inline]
#1: ffff88805d49cd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:40 [inline]
#1: ffff88805d49cd28 (&dev->lock){+.+.}-{4:4}, at: dev_change_flags+0x120/0x270 net/core/dev_api.c:67
stack backtrace:
CPU: 0 UID: 0 PID: 5502 Comm: dhcpcd Not tainted 6.14.0-rc5-syzkaller-01152-g48c57a49c50a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
print_deadlock_bug+0x483/0x620 kernel/locking/lockdep.c:3039
check_deadlock kernel/locking/lockdep.c:3091 [inline]
validate_chain+0x15e2/0x5920 kernel/locking/lockdep.c:3893
__lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730
netdev_lock include/linux/netdevice.h:2731 [inline]
netif_napi_add_weight include/linux/netdevice.h:2763 [inline]
lapbeth_new_device drivers/net/wan/lapbether.c:415 [inline]
lapbeth_device_event+0x766/0xa20 drivers/net/wan/lapbether.c:460
notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85
__dev_notify_flags+0x207/0x400
netif_change_flags+0xf0/0x1a0 net/core/dev.c:9443
dev_change_flags+0x146/0x270 net/core/dev_api.c:68
devinet_ioctl+0xea2/0x1d80 net/ipv4/devinet.c:1200
inet_ioctl+0x3d7/0x4f0 net/ipv4/af_inet.c:1001
sock_do_ioctl+0x158/0x460 net/socket.c:1190
sock_ioctl+0x626/0x8e0 net/socket.c:1309
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:906 [inline]
__se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa6ff44ed49
Code: 5c c3 48 8d 44 24 08 48 89 54 24 e0 48 89 44 24 c0 48 8d 44 24 d0 48 89 44 24 c8 b8 10 00 00 00 c7 44 24 b8 10 00 00 00 0f 05 <41> 89 c0 3d 00 f0 ff ff 76 10 48 8b 15 ae 60 0d 00 f7 d8 41 83 c8
RSP: 002b:00007ffdbfdc91f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa6ff3806c0 RCX: 00007fa6ff44ed49
RDX: 00007ffdbfdd93e8 RSI: 0000000000008914 RDI: 0000000000000018
RBP: 00007ffdbfde95a8 R08: 00007ffdbfdd93a8 R09: 00007ffdbfdd9358
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffdbfdd93e8 R14: 0000000000000028 R15: 0000000000008914