syzbot


INFO: task hung in netdev_run_todo (4)

Status: upstream: reported on 2024/10/09 19:06
Subsystems: wireguard
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+894cca71fa925aabfdb2@syzkaller.appspotmail.com
First crash: 653d, last: 1d09h
✨ AI Jobs (3)
ID Workflow Result Correct Bug Created Started Finished Revision Error
7e78fae6-acec-4f68-a43b-ee35b36dbdb4 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ✅ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ INFO: task hung in netdev_run_todo (4) 2026/06/01 02:23 2026/06/01 02:23 2026/06/01 03:31 6b4a844333e83556da95d61d7f207e7ef5cd4bc6
ca4c1867-0c67-4c72-a3f4-9c380e90a0ff assessment-security 💥 INFO: task hung in netdev_run_todo (4) 2026/05/15 10:03 2026/05/15 10:03 2026/05/15 10:04 9cd3beaadf14b3a22d15fd97a0bf081ee41ebe01 failed to run ["make" "KERNELVERSION=syzkaller" "KERNELRELEASE=syzkaller" "LOCALVERSION=-syzkaller" "-j" "32" "ARCH=x86_64" "CC=ccache clang" "LD=ld.lld" "O=/app/workdir/cache/build/379a897e6824b2dfa101bafec7b477e8ef3a7e62" "-s" "bzImage" "compile_commands.json"]: exit status 2 /app/workdir/cache/src/1e39944fbafaaa3768fe503059b27f6727d79506/lib/maple_tree.c:3514:20: warning: stack frame size (2424) exceeds limit (2048) in 'mas_wr_store_entry' [-Wframe-larger-than] 3514 | static inline void mas_wr_store_entry(struct ma_wr_state *wr_mas) | ^ 1 warning generated. fatal error: error in backend: IO failure on output stream: No space left on device PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script. Stack dump: 0. Program arguments: /usr/bin/clang --target=x86_64-linux-gnu -fintegrated-as -Werror=unknown-warning-option -Werror=ignored-optimization-argument -Werror=option-ignored -Werror=unused-command-line-argument -fmacro-prefix-map=/app/workdir/cache/src/1e39944fbafaaa3768fe503059b27f6727d79506/= -fshort-wchar -funsigned-char -fno-common -fno-PIE -fno-strict-aliasing -std=gnu11 -fms-extensions -Wno-gnu -Wno-microsoft-anon-tag -mno-sse -mno-mmx -mno-sse2 -mno-3dnow -mno-avx -mno-sse4a -fcf-protection=branch -fno-jump-tables -m64 -falign-loops=1 -mno-80387 -mno-fp-ret-in-387 -mstack-alignment=8 -mskip-rax-setup -march=x86-64 -mtune=generic -mno-red-zone -mcmodel=kernel -mstack-protector-guard-reg=gs -mstack-protector-guard-symbol=__ref_stack_chk_guard -Wno-sign-compare -fno-asynchronous-unwind-tables -mretpoline-external-thunk -mindirect-branch-cs-prefix -mfunction-return=thunk-extern -fpatchable-function-entry=16,16 -fno-delete-null-pointer-checks -O2 -fstack-protector-strong -fomit-frame-pointer -ftrivial-auto-var-init=zero -fno-stack-clash-protection -falign-functions=16 -fstrict-flex-arrays=3 -fno-strict-overflow -fno-stack-check -fno-builtin-wcslen -Wall -Wextra -Wundef -Werror=implicit-function-declaration -Werror=implicit-int -Werror=return-type -Werror=strict-prototypes -Wno-format-security -Wno-trigraphs -Wno-frame-address -Wno-address-of-packed-member -Wmissing-declarations -Wmissing-prototypes -Wframe-larger-than=2048 -Wno-format-overflow-non-kprintf -Wno-format-truncation-non-kprintf -Wno-default-const-init-unsafe -Wno-type-limits -Wno-pointer-sign -Wcast-function-type -Wno-unterminated-string-initialization -Wimplicit-fallthrough -Werror=date-time -Werror=incompatible-pointer-types -Wenum-conversion -Wunused -Wno-unused-but-set-variable -Wno-unused-const-variable -Wno-format-overflow -Wno-override-init -Wno-pointer-to-enum-cast -Wno-tautological-constant-out-of-range-compare -Wno-unaligned-access -Wno-enum-compare-conditional -Wno-missing-field-initializers -Wno-shift-negative-value -Wno-enum-enum-conversion -Wno-sign-compare -Wno-unused-parameter -g -gdwarf-4 -fsanitize=kernel-address -mllvm -asan-mapping-offset=0xdffffc0000000000 -mllvm -asan-instrumentation-with-call-threshold=10000 -mllvm -asan-stack=1 -mllvm -asan-globals=1 -mllvm -asan-kernel-mem-intrinsic-prefix=1 -fsanitize=array-bounds -fsanitize=shift -fsanitize-coverage=trace-pc -fsanitize-coverage=trace-cmp -fdebug-info-for-profiling -mllvm -enable-fs-discriminator=true -mllvm -improved-fs-discriminator=true -fbasic-block-address-map -nostdinc -I/app/workdir/cache/src/1e39944fbafaaa3768fe503059b27f6727d79506/arch/x86/include -I./arch/x86/include/generated -I/app/workdir/cache/src/1e39944fbafaaa3768fe503059b27f6727d79506/include -I./include -I/app/workdir/cache/src/1e39944fbafaaa3768fe503059b27f6727d79506/arch/x86/include/uapi -I./arch/x86/include/generated/uapi -I/app/workdir/cache/src/1e39944fbafaaa3768fe503059b27f6727d79506/include/uapi -I./include/generated/uapi -include /app/workdir/cache/src/1e39944fbafaaa3768fe503059b27f6727d79506/include/linux/compiler-version.h -include /app/workdir/cache/src/1e39944fbafaaa3768fe503059b27f6727d79506/include/linux/kconfig.h -include /app/workdir/cache/src/1e39944fbafaaa3768fe503059b27
a523f87b-dddb-4709-b009-c24d923b52ca repro INFO: task hung in netdev_run_todo (4) 2026/03/07 09:34 2026/03/07 09:34 2026/03/07 09:43 31e9c887f7dc24e04b3ca70d0d54fc34141844b0
Discussions (7)
Title Replies (including bot) Last reply
[syzbot] Monthly wireless report (Apr 2026) 0 (1) 2026/04/01 07:42
[syzbot] Monthly wireguard report (Mar 2026) 0 (1) 2026/03/19 21:35
[syzbot] Monthly wireguard report (Nov 2025) 0 (1) 2025/11/30 10:08
[syzbot] Monthly wireguard report (May 2025) 0 (1) 2025/05/12 06:34
[syzbot] Monthly wireguard report (Feb 2025) 0 (1) 2025/02/26 15:11
[syzbot] Monthly wireguard report (Dec 2024) 0 (1) 2024/12/26 09:01
[syzbot] [net?] INFO: task hung in netdev_run_todo (4) 0 (1) 2024/10/09 19:06
Similar bugs (17)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in netdev_run_todo (3) 1 15 1305d 1621d 0/1 auto-obsoleted due to no activity on 2023/03/07 08:19
linux-6.6 INFO: task hung in netdev_run_todo 1 1 272d 272d 0/2 auto-obsoleted due to no activity on 2025/12/14 15:00
linux-5.15 INFO: task hung in netdev_run_todo (3) 1 1 160d 160d 0/3 auto-obsoleted due to no activity on 2026/04/05 15:48
upstream INFO: task hung in netdev_run_todo net 1 12 2479d 3034d 0/29 closed as invalid on 2019/10/23 07:29
linux-4.19 INFO: task hung in netdev_run_todo (2) 1 3 2112d 2160d 0/1 auto-closed as invalid on 2020/12/20 04:57
android-44 INFO: task hung in netdev_run_todo 1 1 2973d 2973d 0/2 auto-closed as invalid on 2019/02/22 12:49
android-6-12 INFO: task hung in netdev_run_todo (2) 1 82 11h54m 133d 0/1 premoderation: reported on 2026/01/22 03:02
linux-4.19 INFO: task hung in netdev_run_todo 1 1 2438d 2438d 0/1 auto-closed as invalid on 2020/01/29 06:48
upstream INFO: task hung in netdev_run_todo (3) net 1 24 716d 754d 0/29 auto-obsoleted due to no activity on 2024/08/07 04:24
linux-5.15 INFO: task hung in netdev_run_todo 1 1 951d 951d 0/3 auto-obsoleted due to no activity on 2024/02/04 09:09
linux-6.6 INFO: task hung in netdev_run_todo (2) 1 1 140d 140d 0/2 auto-obsoleted due to no activity on 2026/04/24 20:32
upstream INFO: task hung in netdev_run_todo (2) staging wireguard usb 1 C error 241 842d 1998d 0/29 auto-obsoleted due to no activity on 2024/05/05 22:51
android-49 INFO: task hung in netdev_run_todo 1 1 2966d 2965d 0/3 auto-closed as invalid on 2019/02/22 14:57
linux-4.14 INFO: task hung in netdev_run_todo 1 1 1298d 1298d 0/1 auto-obsoleted due to no activity on 2023/03/13 17:45
android-6-12 INFO: task hung in netdev_run_todo 1 184 202d 347d 0/1 auto-obsoleted due to no activity on 2026/01/03 01:56
linux-5.15 INFO: task hung in netdev_run_todo (2) 1 54 563d 744d 0/3 auto-obsoleted due to no activity on 2025/01/26 20:30
upstream INFO: task can't die in netdev_run_todo net 1 syz error 2 1721d 2114d 0/29 auto-obsoleted due to no activity on 2023/04/16 04:59

Sample crash report:
INFO: task syz-executor:8454 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:18936 pid:8454  tgid:8454  ppid:1      task_flags:0x40054c flags:0x00080003
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x16ec/0x5620 kernel/sched/core.c:7189
 __schedule_loop kernel/sched/core.c:7268 [inline]
 rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7564
 rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1662
 rt_mutex_s[  700.439609][   T38]  __rt_mutex_slowlock kernel/locking/rtmutex.c:1739 [inline]
 rt_mutex_s[  700.439609][   T38]  __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1779 [inline]
 rt_mutex_s[  700.439609][   T38]  rt_mutex_slowlock+0x2dc/0x780 kernel/locking/rtmutex.c:1819
 __rt_mutex_lock kernel/locking/rtmutex.c:1834 [inline]
 __mutex_lock_common kernel/locking/rtmutex_api.c:535 [inline]
 mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:553
 rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
 netdev_run_todo+0x2e0/0xde0 net/core/dev.c:11694
 tun_detach drivers/net/tun.c:640 [inline]
 tun_chr_close+0x13f/0x1c0 drivers/net/tun.c:3441
 __fput+0x461/0xa70 fs/file_table.c:510
 task_work_run+0x1d9/0x270 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x70f/0x22c0 kernel/exit.c:976
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1119
 get_signal+0x1284/0x1330 kernel/signal.c:3037
 arch_do_signal_or_restart+0xbc/0x840 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0xa9/0x680 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8e78dad68e
RSP: 002b:00007ffc74537988 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: 000000000000008c RBX: 0000555558f46500 RCX: 00007f8e78dad68e
RDX: 000000000000008c RSI: 00007f8e79b94670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffc74537a04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f8e79b94670 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
5 locks held by rcuc/1/28:
4 locks held by ksoftirqd/1/30:
1 lock held by khungtaskd/38:
 #0: ffffffff8dfc8000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8dfc8000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffffffff8dfc8000 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u9:0/59:
 #0: ffff88803e3eb938 ((wq_completion)hci8){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff88803e3eb938 ((wq_completion)hci8){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
 #1: ffffc9000125fc40 ((work_completion)(&hdev->power_on)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
 #1: ffffc9000125fc40 ((work_completion)(&hdev->power_on)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
 #2: ffff888094544f80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_open net/bluetooth/hci_core.c:429 [inline]
 #2: ffff888094544f80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_power_on+0x1ac/0x710 net/bluetooth/hci_core.c:923
 #3: ffff888094545000 (&hdev->req_wait_q){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
 #3: ffff888094545000 (&hdev->req_wait_q){+.+.}-{3:3}, at: finish_wait+0xbe/0x1e0 kernel/sched/wait.c:394
3 locks held by kworker/u8:6/160:
 #0: ffff88801a074138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff88801a074138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
 #1: ffffc90002fe7c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
 #1: ffffc90002fe7c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
 #2: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
5 locks held by kworker/u8:12/3410:
 #0: ffff88801b290938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff88801b290938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
 #1: ffffc9000fee7c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
 #1: ffffc9000fee7c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
 #2: ffffffff8f340e20 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:673
 #3: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
 #3: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x2a4/0x940 net/core/net_namespace.c:248
 #4: ffffffff8dfce1b0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
2 locks held by dhcpcd/5262:
 #0: ffff88803bc7a928 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2409
 #1: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6865
2 locks held by getty/5360:
 #0: ffff888037b430a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211
4 locks held by kworker/u9:3/5613:
3 locks held by kworker/0:4/5716:
 #0: ffff88801a037938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff88801a037938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
 #1: ffffc9000518fc40 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
 #1: ffffc9000518fc40 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
 #2: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
3 locks held by kworker/1:6/5742:
 #0: ffff88801a037938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff88801a037938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
 #1: ffffc9000532fc40 (rx_mode_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
 #1: ffffc9000532fc40 (rx_mode_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
 #2: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: netdev_rx_mode_work+0x1c/0x450 net/core/dev_addr_lists.c:1312
5 locks held by kworker/u8:16/6856:
5 locks held by kworker/u8:31/6872:
11 locks held by kworker/u8:36/6878:
3 locks held by kworker/u8:38/6880:
 #0: ffff888033367138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff888033367138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
 #1: ffffc90003cbfc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
 #1: ffffc90003cbfc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
 #2: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #2: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4206
1 lock held by syz.5.639/8007:
 #0: ffffffff8dfce1b0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
1 lock held by syz-executor/8454:
 #0: ffffffff8dfce1b0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
1 lock held by syz-executor/8462:
 #0: ffffffff8dfce1b0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
1 lock held by syz-executor/8490:
 #0: ffffffff8dfce1b0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
1 lock held by syz-executor/8504:
 #0: ffffffff8dfce1b0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
1 lock held by syz-executor/8538:
 #0: ffffffff8dfce1b0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
1 lock held by syz-executor/8561:
 #0: ffffffff8dfce1b0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
1 lock held by syz-executor/8573:
 #0: ffffffff8dfce1b0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
1 lock held by syz-executor/8600:
 #0: ffffffff8dfce1b0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
1 lock held by syz-executor/8616:
 #0: ffffffff8dfce1b0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
2 locks held by syz-executor/8645:
 #0: ffffffff8f888148 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8f888148 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffffffff8f888148 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
 #1: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #1: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4109
1 lock held by syz-executor/8668:
 #0: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x722/0xbe0 net/core/rtnetlink.c:7003
1 lock held by syz-executor/8681:
 #0: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978
2 locks held by syz-executor/8708:
 #0: ffffffff8f340e20 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:575
 #1: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #1: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: register_netdevice_notifier_net+0x1a/0xa0 net/core/dev.c:2102
1 lock held by syz-executor/8721:
 #0: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978
1 lock held by syz-executor/8738:
 #0: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978
1 lock held by syz-executor/8745:
 #0: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978
1 lock held by syz-executor/8752:
 #0: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8f34fb78 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978
10 locks held by syz-executor/8758:

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x135/0x170 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
 watchdog+0xfd3/0x1030 kernel/hung_task.c:561
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6878 Comm: kworker/u8:36 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: wg-kex-wg2 wg_packet_handshake_send_worker
RIP: 0010:mark_lock_accessed kernel/locking/lockdep.c:1530 [inline]
RIP: 0010:__bfs kernel/locking/lockdep.c:1768 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline]
RIP: 0010:__lock_acquire+0x1839/0x2cf0 kernel/locking/lockdep.c:5237
Code: fd 47 d2 13 4d 85 e4 0f 84 b2 01 00 00 49 8b 44 24 10 48 85 c0 0f 84 1c 0d 00 00 8b 0d e8 47 d2 13 39 48 5c 0f 84 67 ff ff ff <89> 48 5c 49 8b 44 24 30 48 85 c0 74 25 41 0f b6 4c 24 2a 89 ca 80
RSP: 0018:ffffc90003cdebd0 EFLAGS: 00000093
RAX: ffffffff93153568 RBX: 00000000000003cd RCX: 00000000000bea94
RDX: ffffffff95fe3708 RSI: ffff8880325d4b30 RDI: 00000000000003cd
RBP: 1c0cf7658f49741c R08: ffffc90003cdeb98 R09: 0000000000000020
R10: dffffc0000000000 R11: ffffffff81a0a260 R12: ffffffff95fee678
R13: ffff8880325d4b30 R14: ffff8880325d3d80 R15: 000000000000058b
FS:  0000000000000000(0000) GS:ffff888126183000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f33998b3ed0 CR3: 0000000038d20000 CR4: 00000000003526f0
DR0: 0000000000009a40 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
 _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
 lock_hrtimer_base kernel/time/hrtimer.c:191 [inline]
 hrtimer_start_range_ns+0xc3/0xef0 kernel/time/hrtimer.c:1489
 enqueue_task+0x75/0x410 kernel/sched/core.c:2165
 sched_change_end+0x22b/0x5f0 kernel/sched/core.c:11207
 migrate_disable_switch kernel/sched/core.c:2425 [inline]
 __schedule+0x1889/0x5620 kernel/sched/core.c:7045
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7513
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
 irqentry_exit+0x14f/0x8b0 kernel/entry/common.c:164
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x124/0x2550 arch/x86/kernel/unwind_orc.c:498
Code: 48 03 00 00 48 c7 c2 a0 b3 49 8b e8 d6 bb 29 00 4c 89 64 24 78 48 89 5c 24 70 49 8d 5e 50 48 89 d8 48 c1 e8 03 48 89 44 24 40 <80> 3c 28 00 74 08 48 89 df e8 3e d4 b4 00 48 89 5c 24 28 48 8b 1b
RSP: 0018:ffffc90003cdf258 EFLAGS: 00000a06
RAX: 1ffff9200079be7b RBX: ffffc90003cdf3d8 RCX: 0000000080000001
RDX: 00000000995a2a14 RSI: ffffffff8ba759c0 RDI: ffffffff8ba75980
RBP: dffffc0000000000 R08: ffffffff8176c226 R09: ffffffff8dfc8000
R10: ffffc90003cdf388 R11: fffff5200079be7d R12: ffffc90003cdf3c0
R13: 1ffff9200079be71 R14: ffffc90003cdf388 R15: ffffffff8176c226
 __unwind_start+0x5b8/0x760 arch/x86/kernel/unwind_orc.c:787
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2689 [inline]
 slab_free mm/slub.c:6251 [inline]
 kmem_cache_free+0x187/0x6c0 mm/slub.c:6378
 kfree_skb_reason include/linux/skbuff.h:1324 [inline]
 kfree_skb include/linux/skbuff.h:1333 [inline]
 send6+0x50f/0x910 drivers/net/wireguard/socket.c:157
 wg_socket_send_skb_to_peer+0x128/0x200 drivers/net/wireguard/socket.c:177
 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline]
 wg_packet_handshake_send_worker+0x203/0x350 drivers/net/wireguard/send.c:51
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (891):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/02 09:51 upstream 6f3ed7fec72f 1095583b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in netdev_run_todo
2026/06/02 02:44 upstream e43ffb69e043 1095583b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in netdev_run_todo
2026/05/24 22:01 upstream 4cbfe4502e3d c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in netdev_run_todo
2026/05/24 08:44 upstream 4cbfe4502e3d c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in netdev_run_todo
2026/05/22 09:48 upstream 6779b50faa56 e16cf9f3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in netdev_run_todo
2026/05/20 05:57 upstream 27fa82620cba 0909d65f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in netdev_run_todo
2026/05/20 03:09 upstream 27fa82620cba 0909d65f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in netdev_run_todo
2026/05/17 23:49 upstream e5d505e3664b de5aae85 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in netdev_run_todo
2026/05/12 04:56 upstream 50897c955902 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in netdev_run_todo
2026/05/07 05:31 upstream 5862221fdded f250db59 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in netdev_run_todo
2026/05/02 23:25 upstream f1a5e78a55eb a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in netdev_run_todo
2026/04/14 05:15 upstream 26ff969926a0 1a086e7c .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in netdev_run_todo
2026/03/03 01:01 upstream af4e9ef3d784 28b83e23 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in netdev_run_todo
2025/07/21 21:41 upstream 89be9a83ccf1 0b3788a0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2024/10/06 16:49 upstream 8f602276d390 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in netdev_run_todo
2024/09/27 16:51 upstream 075dbe9f6e3c 2b1784d6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in netdev_run_todo
2025/07/06 03:02 upstream 05df91921da6 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: task hung in netdev_run_todo
2025/02/25 10:53 upstream d082ecbc71e9 d34966d1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-compat INFO: task hung in netdev_run_todo
2024/09/21 15:34 upstream 1868f9d0260e 6f888b75 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64 INFO: task hung in netdev_run_todo
2026/02/23 16:33 net d4f687fbbce4 305c0ec5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in netdev_run_todo
2025/09/23 05:22 net-next 78e87f9d5358 0ac7291c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in netdev_run_todo
2026/06/03 06:00 linux-next f7af91adc230 3c0d2131 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/06/01 10:25 linux-next f7af91adc230 8d8eeb3a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/06/01 05:45 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/06/01 04:30 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/06/01 03:19 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/06/01 01:57 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/06/01 00:39 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/31 23:08 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/31 20:38 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/31 19:13 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/31 17:19 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/31 14:02 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/05/31 11:55 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/05/30 19:02 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/30 17:03 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/05/30 14:04 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/05/30 12:51 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/05/30 10:00 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/30 09:11 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/05/29 21:25 linux-next f7af91adc230 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/05/27 14:16 linux-next e7e28506af98 769cbc61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/26 22:30 linux-next e7e28506af98 2b01f00e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/25 21:55 linux-next c1ecb239fa34 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/25 06:01 linux-next c1ecb239fa34 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/05/25 00:06 linux-next c1ecb239fa34 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/05/24 00:46 linux-next c1ecb239fa34 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/05/23 22:30 linux-next c1ecb239fa34 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/05/23 21:28 linux-next c1ecb239fa34 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/23 20:25 linux-next c1ecb239fa34 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/20 23:12 linux-next 687da68900cd 41b8c833 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/18 04:25 linux-next e98d21c170b0 de5aae85 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/15 05:08 linux-next e98d21c170b0 6ccb967e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/05/12 21:56 linux-next e98d21c170b0 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/12 03:33 linux-next e98d21c170b0 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/07 01:30 linux-next 735d2f48cada cbcd9ea0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2026/05/04 05:19 linux-next b9303e6bff70 a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in netdev_run_todo
2026/05/03 14:48 linux-next b9303e6bff70 a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2025/08/22 05:15 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next 8f5ae30d69d7 bf27483f .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 INFO: task hung in netdev_run_todo
* Struck through repros no longer work on HEAD.