Extracting prog: 6m36.120490239s Minimizing prog: 54m29.939525216s Simplifying prog options: 19m24.882407293s Extracting C: 5m10.149673698s Simplifying C: 0s extracting reproducer from 28 programs testing a last program of every proc single: executing 8 programs separately with timeout 6m0s testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$unix-socket$inet_udp-setsockopt$ARPT_SO_SET_REPLACE-ioctl$sock_SIOCETHTOOL detailed listing: executing program 0: r0 = socket$unix(0x1, 0x5, 0x0) r1 = socket$inet_udp(0x2, 0x2, 0x0) setsockopt$ARPT_SO_SET_REPLACE(r1, 0xa02000000000000, 0x60, &(0x7f0000000000)={'filter\x00', 0xb001, 0x4, 0x3e8, 0x218, 0x0, 0x130, 0xa00, 0x300, 0x300, 0x7fffffe, 0x0, {[{{@arp={@local, @empty, 0x0, 0x0, 0x0, 0x0, {}, {@mac=@local}, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 'pimreg\x00', 'veth0_to_bridge\x00'}, 0xc0, 0x130}, @unspec=@NFLOG={0x70, 'NFLOG\x00', 0x0, {0x0, 0x0, 0x0, 0x0, 0x0, "f67b23ffdfa27f907a03732da3acbc6518e62a77ca06f258762e88c0d9f9d2f413b94a105f4bdf01425ce81c5d000000000000000500ffffffff00"}}}, {{@arp={@multicast2, @empty, 0x0, 0x0, 0x0, 0x0, {}, {}, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 'veth0_to_team\x00', 'ip6tnl0\x00'}, 0xc0, 0xe8}, @unspec=@CLASSIFY={0x28}}, {{@uncond, 0xc0, 0xe8}, @unspec=@NFQUEUE3={0x28}}], {{'\x00', 0xc0, 0xe8}, {0x28}}}}, 0x438) ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f0000000080)={'bridge0\x00', &(0x7f0000000000)=@ethtool_regs={0x4, 0x0, 0x15, "f42a97b96d025891dd3f75fdda624457ad3d5c3638"}}) program crashed: INFO: task hung in rtnl_lock single: successfully extracted reproducer found reproducer with 4 syscalls minimizing guilty program testing program (duration=8m43.528133211s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$unix-socket$inet_udp-setsockopt$ARPT_SO_SET_REPLACE detailed listing: executing program 0: socket$unix(0x1, 0x5, 0x0) r0 = socket$inet_udp(0x2, 0x2, 0x0) setsockopt$ARPT_SO_SET_REPLACE(r0, 0xa02000000000000, 0x60, &(0x7f0000000000)={'filter\x00', 0xb001, 0x4, 0x3e8, 0x218, 0x0, 0x130, 0xa00, 0x300, 0x300, 0x7fffffe, 0x0, {[{{@arp={@local, @empty, 0x0, 0x0, 0x0, 0x0, {}, {@mac=@local}, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 'pimreg\x00', 'veth0_to_bridge\x00'}, 0xc0, 0x130}, @unspec=@NFLOG={0x70, 'NFLOG\x00', 0x0, {0x0, 0x0, 0x0, 0x0, 0x0, "f67b23ffdfa27f907a03732da3acbc6518e62a77ca06f258762e88c0d9f9d2f413b94a105f4bdf01425ce81c5d000000000000000500ffffffff00"}}}, {{@arp={@multicast2, @empty, 0x0, 0x0, 0x0, 0x0, {}, {}, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 'veth0_to_team\x00', 'ip6tnl0\x00'}, 0xc0, 0xe8}, @unspec=@CLASSIFY={0x28}}, {{@uncond, 0xc0, 0xe8}, @unspec=@NFQUEUE3={0x28}}], {{'\x00', 0xc0, 0xe8}, {0x28}}}}, 0x438) program did not crash testing program (duration=8m43.528133211s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$unix-socket$inet_udp-ioctl$sock_SIOCETHTOOL detailed listing: executing program 0: r0 = socket$unix(0x1, 0x5, 0x0) socket$inet_udp(0x2, 0x2, 0x0) ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f0000000080)={'bridge0\x00', &(0x7f0000000000)=@ethtool_regs={0x4, 0x0, 0x15, "f42a97b96d025891dd3f75fdda624457ad3d5c3638"}}) program crashed: INFO: task hung in rtnl_lock testing program (duration=8m43.528133211s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$unix-ioctl$sock_SIOCETHTOOL detailed listing: executing program 0: r0 = socket$unix(0x1, 0x5, 0x0) ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f0000000080)={'bridge0\x00', &(0x7f0000000000)=@ethtool_regs={0x4, 0x0, 0x15, "f42a97b96d025891dd3f75fdda624457ad3d5c3638"}}) program crashed: INFO: task hung in rtnl_lock testing program (duration=8m43.528133211s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): ioctl$sock_SIOCETHTOOL detailed listing: executing program 0: ioctl$sock_SIOCETHTOOL(0xffffffffffffffff, 0x89f0, &(0x7f0000000080)={'bridge0\x00', &(0x7f0000000000)=@ethtool_regs={0x4, 0x0, 0x15, "f42a97b96d025891dd3f75fdda624457ad3d5c3638"}}) program did not crash testing program (duration=8m43.528133211s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$unix-ioctl$sock_SIOCETHTOOL detailed listing: executing program 0: r0 = socket$unix(0x1, 0x5, 0x0) ioctl$sock_SIOCETHTOOL(r0, 0x89f0, 0x0) program did not crash testing program (duration=8m43.528133211s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$unix-ioctl$sock_SIOCETHTOOL detailed listing: executing program 0: r0 = socket$unix(0x1, 0x5, 0x0) ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f0000000080)={'bridge0\x00', 0x0}) program did not crash testing program (duration=8m43.528133211s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$unix-ioctl$sock_SIOCETHTOOL detailed listing: executing program 0: r0 = socket$unix(0x1, 0x5, 0x0) ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f0000000080)={'bridge0\x00', &(0x7f0000000000)=@ethtool_regs}) program did not crash extracting C reproducer testing compiled C program (duration=8m43.528133211s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$unix-ioctl$sock_SIOCETHTOOL program crashed: no output from test machine a never seen crash title: no output from test machine, ignore simplifying guilty program options testing program (duration=8m43.528133211s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 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:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$unix-ioctl$sock_SIOCETHTOOL detailed listing: executing program 0: r0 = socket$unix(0x1, 0x5, 0x0) ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f0000000080)={'bridge0\x00', &(0x7f0000000000)=@ethtool_regs={0x4, 0x0, 0x15, "f42a97b96d025891dd3f75fdda624457ad3d5c3638"}}) program crashed: INFO: task hung in rtnl_lock extracting C reproducer testing compiled C program (duration=8m43.528133211s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 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:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$unix-ioctl$sock_SIOCETHTOOL program crashed: no output from test machine a never seen crash title: no output from test machine, ignore testing program (duration=8m43.528133211s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 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:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$unix-ioctl$sock_SIOCETHTOOL detailed listing: executing program 0: r0 = socket$unix(0x1, 0x5, 0x0) ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f0000000080)={'bridge0\x00', &(0x7f0000000000)=@ethtool_regs={0x4, 0x0, 0x15, "f42a97b96d025891dd3f75fdda624457ad3d5c3638"}}) program did not crash testing program (duration=8m43.528133211s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 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:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$unix-ioctl$sock_SIOCETHTOOL detailed listing: executing program 0: r0 = socket$unix(0x1, 0x5, 0x0) ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f0000000080)={'bridge0\x00', &(0x7f0000000000)=@ethtool_regs={0x4, 0x0, 0x15, "f42a97b96d025891dd3f75fdda624457ad3d5c3638"}}) program crashed: INFO: task hung in rtnl_lock validation run: crashed=true testing program (duration=8m43.528133211s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 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:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$unix-ioctl$sock_SIOCETHTOOL detailed listing: executing program 0: r0 = socket$unix(0x1, 0x5, 0x0) ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f0000000080)={'bridge0\x00', &(0x7f0000000000)=@ethtool_regs={0x4, 0x0, 0x15, "f42a97b96d025891dd3f75fdda624457ad3d5c3638"}}) program crashed: INFO: task hung in rtnl_lock validation run: crashed=true testing program (duration=8m43.528133211s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 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:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$unix-ioctl$sock_SIOCETHTOOL detailed listing: executing program 0: r0 = socket$unix(0x1, 0x5, 0x0) ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f0000000080)={'bridge0\x00', &(0x7f0000000000)=@ethtool_regs={0x4, 0x0, 0x15, "f42a97b96d025891dd3f75fdda624457ad3d5c3638"}}) program crashed: INFO: task hung in rtnl_lock validation run: crashed=true reproducing took 1h39m48.325100751s repro crashed as (corrupted=false): INFO: task kworker/u8:0:12 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:0 state:D stack:0 pid:12 tgid:12 ppid:2 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:5996 [inline] __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843 __schedule_loop kernel/sched/core.c:7924 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7939 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79 addrconf_dad_work+0xce/0x1530 net/ipv6/addrconf.c:4234 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3319 worker_thread+0xc70/0x10b0 kernel/workqueue.c:3400 kthread+0x2c9/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task syz-executor:461 blocked for more than 123 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:461 tgid:461 ppid:1 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5996 [inline] __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843 __schedule_loop kernel/sched/core.c:7924 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7939 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6672 netlink_rcv_skb+0x256/0x4f0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6693 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7fe/0xb10 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x718/0x790 net/socket.c:2217 __do_sys_sendto net/socket.c:2229 [inline] __se_sys_sendto net/socket.c:2225 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2225 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f54d8b560d7 RSP: 002b:00007fff33d50fb0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055557cc2d500 RCX: 00007f54d8b560d7 RDX: 000000000000002c RSI: 00007f54d9944670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007fff33d51014 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f54d9944670 R15: 0000000000000000 INFO: task syz-executor:463 blocked for more than 124 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:463 tgid:463 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5996 [inline] __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843 __schedule_loop kernel/sched/core.c:7924 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7939 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6672 netlink_rcv_skb+0x256/0x4f0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6693 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7fe/0xb10 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x718/0x790 net/socket.c:2217 __do_sys_sendto net/socket.c:2229 [inline] __se_sys_sendto net/socket.c:2225 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2225 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fefaa7560d7 RSP: 002b:00007ffc32c8d780 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000555591eac500 RCX: 00007fefaa7560d7 RDX: 0000000000000028 RSI: 00007fefab544670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffc32c8d7e4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007fefab544670 R15: 0000000000000000 INFO: task syz-executor:466 blocked for more than 125 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:466 tgid:466 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5996 [inline] __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843 __schedule_loop kernel/sched/core.c:7924 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7939 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6672 netlink_rcv_skb+0x256/0x4f0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6693 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7fe/0xb10 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x718/0x790 net/socket.c:2217 __do_sys_sendto net/socket.c:2229 [inline] __se_sys_sendto net/socket.c:2225 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2225 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fab6f5560d7 RSP: 002b:00007ffc9c22a7e0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00005555733de500 RCX: 00007fab6f5560d7 RDX: 0000000000000028 RSI: 00007fab70344670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffc9c22a844 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007fab70344670 R15: 0000000000000000 INFO: task syz-executor:467 blocked for more than 126 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:467 tgid:467 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5996 [inline] __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843 __schedule_loop kernel/sched/core.c:7924 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7939 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6672 netlink_rcv_skb+0x256/0x4f0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6693 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7fe/0xb10 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x718/0x790 net/socket.c:2217 __do_sys_sendto net/socket.c:2229 [inline] __se_sys_sendto net/socket.c:2225 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2225 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f86119560d7 RSP: 002b:00007fffb7fd31f0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00005555787d1500 RCX: 00007f86119560d7 RDX: 0000000000000028 RSI: 00007f8612744670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007fffb7fd3254 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f8612744670 R15: 0000000000000000 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 d2070f6ccd239e5a47ec9c1c2f682235c3170fcc Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120 dump_stack+0x19/0x20 lib/dump_stack.c:129 nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline] watchdog+0xdad/0xf00 kernel/hung_task.c:423 kthread+0x2c9/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 20 Comm: rcuop/0 Not tainted syzkaller #0 d2070f6ccd239e5a47ec9c1c2f682235c3170fcc Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:list_empty include/linux/list.h:373 [inline] RIP: 0010:___rmqueue_pcplist+0x287/0x31b0 mm/page_alloc.c:3214 Code: 48 89 84 24 18 01 00 00 4c 89 8c 24 b0 00 00 00 49 6b c1 68 48 89 44 24 20 4c 89 7c 24 78 4c 89 fb 48 c1 eb 03 42 80 3c 2b 00 <74> 08 4c 89 ff e8 af b3 05 00 49 8b 07 4c 39 f8 0f 84 1e 01 00 00 RSP: 0018:ffffc9000022fd60 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 1ffff1103edee454 RCX: ffffffff8635a480 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff87e37c00 RBP: ffffc9000022ffd0 R08: ffff8881f6f72280 R09: 0000000000000000 R10: 0000000000000000 R11: 00000000ffffffff R12: ffff8881f6f722a0 R13: dffffc0000000000 R14: ffff8881f6f72280 R15: ffff8881f6f722a0 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5d44b45000 CR3: 000000011f8c4000 CR4: 00000000003526b0 Call Trace: __rmqueue_pcplist mm/page_alloc.c:3263 [inline] rmqueue_pcplist mm/page_alloc.c:3292 [inline] rmqueue mm/page_alloc.c:3325 [inline] get_page_from_freelist+0x6f5/0x4a20 mm/page_alloc.c:3911 __alloc_pages_noprof+0x35f/0x7e0 mm/page_alloc.c:5264 alloc_slab_page+0x6b/0x1e0 mm/slub.c:-1 allocate_slab+0x69/0x420 mm/slub.c:2687 new_slab mm/slub.c:2741 [inline] ___slab_alloc+0x5a2/0x8d0 mm/slub.c:3934 __slab_alloc mm/slub.c:4025 [inline] __slab_alloc_node mm/slub.c:4078 [inline] slab_alloc_node mm/slub.c:4239 [inline] kmem_cache_alloc_node_noprof+0x29b/0x420 mm/slub.c:4305 __alloc_skb+0x108/0x370 net/core/skbuff.c:677 alloc_skb include/linux/skbuff.h:1331 [inline] nlmsg_new include/net/netlink.h:1015 [inline] fdb_notify+0x78/0x150 net/bridge/br_fdb.c:195 br_fdb_update+0x4b7/0x680 net/bridge/br_fdb.c:941 br_handle_frame_finish+0x3a3/0x1760 net/bridge/br_input.c:141 nf_hook_bridge_pre net/bridge/br_input.c:301 [inline] br_handle_frame+0x5a6/0xba0 net/bridge/br_input.c:424 __netif_receive_skb_core+0xfae/0x3ab0 net/core/dev.c:5657 __netif_receive_skb_one_core net/core/dev.c:5761 [inline] __netif_receive_skb net/core/dev.c:5876 [inline] process_backlog+0x3e5/0xad0 net/core/dev.c:6212 __napi_poll+0xd3/0x610 net/core/dev.c:6863 napi_poll net/core/dev.c:6932 [inline] net_rx_action+0x5ea/0xd80 net/core/dev.c:7054 handle_softirqs+0x1aa/0x630 kernel/softirq.c:621 __do_softirq+0xf/0x16 kernel/softirq.c:659 do_softirq+0xb8/0x110 kernel/softirq.c:503 __local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_do_batch+0x5d9/0xd40 kernel/rcu/tree.c:2594 nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline] rcu_nocb_cb_kthread+0x524/0xb30 kernel/rcu/tree_nocb.h:957 kthread+0x2c9/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 final repro crashed as (corrupted=false): INFO: task kworker/u8:0:12 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:0 state:D stack:0 pid:12 tgid:12 ppid:2 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:5996 [inline] __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843 __schedule_loop kernel/sched/core.c:7924 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7939 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79 addrconf_dad_work+0xce/0x1530 net/ipv6/addrconf.c:4234 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3319 worker_thread+0xc70/0x10b0 kernel/workqueue.c:3400 kthread+0x2c9/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task syz-executor:461 blocked for more than 123 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:461 tgid:461 ppid:1 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5996 [inline] __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843 __schedule_loop kernel/sched/core.c:7924 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7939 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6672 netlink_rcv_skb+0x256/0x4f0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6693 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7fe/0xb10 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x718/0x790 net/socket.c:2217 __do_sys_sendto net/socket.c:2229 [inline] __se_sys_sendto net/socket.c:2225 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2225 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f54d8b560d7 RSP: 002b:00007fff33d50fb0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055557cc2d500 RCX: 00007f54d8b560d7 RDX: 000000000000002c RSI: 00007f54d9944670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007fff33d51014 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f54d9944670 R15: 0000000000000000 INFO: task syz-executor:463 blocked for more than 124 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:463 tgid:463 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5996 [inline] __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843 __schedule_loop kernel/sched/core.c:7924 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7939 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6672 netlink_rcv_skb+0x256/0x4f0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6693 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7fe/0xb10 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x718/0x790 net/socket.c:2217 __do_sys_sendto net/socket.c:2229 [inline] __se_sys_sendto net/socket.c:2225 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2225 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fefaa7560d7 RSP: 002b:00007ffc32c8d780 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000555591eac500 RCX: 00007fefaa7560d7 RDX: 0000000000000028 RSI: 00007fefab544670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffc32c8d7e4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007fefab544670 R15: 0000000000000000 INFO: task syz-executor:466 blocked for more than 125 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:466 tgid:466 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5996 [inline] __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843 __schedule_loop kernel/sched/core.c:7924 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7939 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6672 netlink_rcv_skb+0x256/0x4f0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6693 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7fe/0xb10 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x718/0x790 net/socket.c:2217 __do_sys_sendto net/socket.c:2229 [inline] __se_sys_sendto net/socket.c:2225 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2225 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fab6f5560d7 RSP: 002b:00007ffc9c22a7e0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00005555733de500 RCX: 00007fab6f5560d7 RDX: 0000000000000028 RSI: 00007fab70344670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffc9c22a844 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007fab70344670 R15: 0000000000000000 INFO: task syz-executor:467 blocked for more than 126 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:467 tgid:467 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5996 [inline] __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843 __schedule_loop kernel/sched/core.c:7924 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7939 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6672 netlink_rcv_skb+0x256/0x4f0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6693 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7fe/0xb10 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x718/0x790 net/socket.c:2217 __do_sys_sendto net/socket.c:2229 [inline] __se_sys_sendto net/socket.c:2225 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2225 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f86119560d7 RSP: 002b:00007fffb7fd31f0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00005555787d1500 RCX: 00007f86119560d7 RDX: 0000000000000028 RSI: 00007f8612744670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007fffb7fd3254 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f8612744670 R15: 0000000000000000 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 d2070f6ccd239e5a47ec9c1c2f682235c3170fcc Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120 dump_stack+0x19/0x20 lib/dump_stack.c:129 nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline] watchdog+0xdad/0xf00 kernel/hung_task.c:423 kthread+0x2c9/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 20 Comm: rcuop/0 Not tainted syzkaller #0 d2070f6ccd239e5a47ec9c1c2f682235c3170fcc Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:list_empty include/linux/list.h:373 [inline] RIP: 0010:___rmqueue_pcplist+0x287/0x31b0 mm/page_alloc.c:3214 Code: 48 89 84 24 18 01 00 00 4c 89 8c 24 b0 00 00 00 49 6b c1 68 48 89 44 24 20 4c 89 7c 24 78 4c 89 fb 48 c1 eb 03 42 80 3c 2b 00 <74> 08 4c 89 ff e8 af b3 05 00 49 8b 07 4c 39 f8 0f 84 1e 01 00 00 RSP: 0018:ffffc9000022fd60 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 1ffff1103edee454 RCX: ffffffff8635a480 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff87e37c00 RBP: ffffc9000022ffd0 R08: ffff8881f6f72280 R09: 0000000000000000 R10: 0000000000000000 R11: 00000000ffffffff R12: ffff8881f6f722a0 R13: dffffc0000000000 R14: ffff8881f6f72280 R15: ffff8881f6f722a0 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5d44b45000 CR3: 000000011f8c4000 CR4: 00000000003526b0 Call Trace: __rmqueue_pcplist mm/page_alloc.c:3263 [inline] rmqueue_pcplist mm/page_alloc.c:3292 [inline] rmqueue mm/page_alloc.c:3325 [inline] get_page_from_freelist+0x6f5/0x4a20 mm/page_alloc.c:3911 __alloc_pages_noprof+0x35f/0x7e0 mm/page_alloc.c:5264 alloc_slab_page+0x6b/0x1e0 mm/slub.c:-1 allocate_slab+0x69/0x420 mm/slub.c:2687 new_slab mm/slub.c:2741 [inline] ___slab_alloc+0x5a2/0x8d0 mm/slub.c:3934 __slab_alloc mm/slub.c:4025 [inline] __slab_alloc_node mm/slub.c:4078 [inline] slab_alloc_node mm/slub.c:4239 [inline] kmem_cache_alloc_node_noprof+0x29b/0x420 mm/slub.c:4305 __alloc_skb+0x108/0x370 net/core/skbuff.c:677 alloc_skb include/linux/skbuff.h:1331 [inline] nlmsg_new include/net/netlink.h:1015 [inline] fdb_notify+0x78/0x150 net/bridge/br_fdb.c:195 br_fdb_update+0x4b7/0x680 net/bridge/br_fdb.c:941 br_handle_frame_finish+0x3a3/0x1760 net/bridge/br_input.c:141 nf_hook_bridge_pre net/bridge/br_input.c:301 [inline] br_handle_frame+0x5a6/0xba0 net/bridge/br_input.c:424 __netif_receive_skb_core+0xfae/0x3ab0 net/core/dev.c:5657 __netif_receive_skb_one_core net/core/dev.c:5761 [inline] __netif_receive_skb net/core/dev.c:5876 [inline] process_backlog+0x3e5/0xad0 net/core/dev.c:6212 __napi_poll+0xd3/0x610 net/core/dev.c:6863 napi_poll net/core/dev.c:6932 [inline] net_rx_action+0x5ea/0xd80 net/core/dev.c:7054 handle_softirqs+0x1aa/0x630 kernel/softirq.c:621 __do_softirq+0xf/0x16 kernel/softirq.c:659 do_softirq+0xb8/0x110 kernel/softirq.c:503 __local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_do_batch+0x5d9/0xd40 kernel/rcu/tree.c:2594 nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline] rcu_nocb_cb_kthread+0x524/0xb30 kernel/rcu/tree_nocb.h:957 kthread+0x2c9/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244