INFO: task syz-executor:2268 blocked for more than 122 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:2268 tgid:2268 ppid:1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:6016 [inline]
__schedule+0x1399/0x1fa0 kernel/sched/core.c:7870
__schedule_loop kernel/sched/core.c:7951 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7966
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8023
__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
ip_tunnel_init_net+0x30c/0x890 net/ipv4/ip_tunnel.c:1145
ipgre_init_net+0x28/0x30 net/ipv4/ip_gre.c:1070
ops_init+0x1b2/0x5d0 net/core/net_namespace.c:139
setup_net+0x227/0x9b0 net/core/net_namespace.c:356
copy_net_ns+0x512/0xa30 net/core/net_namespace.c:510
create_new_namespaces+0x3b5/0x720 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228
ksys_unshare+0x502/0x880 kernel/fork.c:3373
__do_sys_unshare kernel/fork.c:3444 [inline]
__se_sys_unshare kernel/fork.c:3442 [inline]
__x64_sys_unshare+0x3c/0x50 kernel/fork.c:3442
x64_sys_call+0x2998/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:273
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: 0033:0x7f78c8f9dae7
RSP: 002b:00007ffd96118d68 EFLAGS: 00000202 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f78c9215f40 RCX: 00007f78c8f9dae7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f78c92167b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffd96118fa8 R15: 0000000000000000
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 9f86d9c18f1652eb5f7cacfb207b3899f57a91b2
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 20 Comm: rcuop/0 Not tainted syzkaller #0 9f86d9c18f1652eb5f7cacfb207b3899f57a91b2
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:stack_depot_save_flags+0x15/0x800 lib/stackdepot.c:588
Code: 68 00 00 eb d8 b8 c7 fd cb d8 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 ec 38 <65> 48 8b 04 25 28 00 00 00 48 89 45 d0 83 f9 04 0f 83 cc 03 00 00
RSP: 0018:ffffc90000007070 EFLAGS: 00000282
RAX: 000000000000001a RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 000000000000001a RDI: ffffc900000070e0
RBP: ffffc900000070d0 R08: ffffc90000007070 R09: ffffc90000007068
R10: 0000000000000019 R11: ffffffff8175d800 R12: ffffea00058750c0
R13: 0000000000000000 R14: ffff888161d433c8 R15: ffffc900000070e0
FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000558a505461f0 CR3: 000000010729e000 CR4: 00000000003526b0
Call Trace:
kasan_save_stack mm/kasan/common.c:50 [inline]
kasan_save_track+0x4f/0x80 mm/kasan/common.c:70
kasan_save_free_info+0x4a/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:249 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:266
kasan_slab_free include/linux/kasan.h:234 [inline]
slab_free_hook mm/slub.c:2445 [inline]
slab_free mm/slub.c:4714 [inline]
kmem_cache_free+0x1bd/0x4f0 mm/slub.c:4825
kfree_skbmem net/core/skbuff.c:-1 [inline]
__kfree_skb+0x18f/0x210 net/core/skbuff.c:1203
sk_skb_reason_drop+0xd8/0x310 net/core/skbuff.c:1240
kfree_skb_reason include/linux/skbuff.h:1271 [inline]
kfree_skb include/linux/skbuff.h:1280 [inline]
ip6_mc_input+0x516/0x6c0 net/ipv6/ip6_input.c:587
dst_input include/net/dst.h:469 [inline]
ip6_rcv_finish+0x360/0x3e0 net/ipv6/ip6_input.c:79
NF_HOOK include/linux/netfilter.h:317 [inline]
ipv6_rcv+0xf1/0x240 net/ipv6/ip6_input.c:309
__netif_receive_skb_one_core net/core/dev.c:5776 [inline]
__netif_receive_skb net/core/dev.c:5889 [inline]
netif_receive_skb_internal net/core/dev.c:5975 [inline]
netif_receive_skb+0x147/0x7b0 net/core/dev.c:6034
br_netif_receive_skb net/bridge/br_input.c:30 [inline]
NF_HOOK include/linux/netfilter.h:317 [inline]
br_pass_frame_up+0x126/0x1b0 net/bridge/br_input.c:70
br_handle_frame_finish+0x1317/0x1760 net/bridge/br_input.c:221
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:5670
__netif_receive_skb_one_core net/core/dev.c:5774 [inline]
__netif_receive_skb net/core/dev.c:5889 [inline]
process_backlog+0x3e5/0xad0 net/core/dev.c:6225
__napi_poll+0xd0/0x610 net/core/dev.c:6876
napi_poll net/core/dev.c:6945 [inline]
net_rx_action+0x5ea/0xd80 net/core/dev.c:7067
handle_softirqs+0x1ad/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
net_ratelimit: 68671 callbacks suppressed
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:4a:b3:9d:be:ed:c6, vlan:0)
net_ratelimit: 88258 callbacks suppressed
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:4a:b3:9d:be:ed:c6, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:4a:b3:9d:be:ed:c6, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:4a:b3:9d:be:ed:c6, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)