INFO: task syz.3.251:1128 blocked for more than 125 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.251 state:D stack:0 pid:1128 tgid:1128 ppid:291 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5945 [inline] __schedule+0x1322/0x1df0 kernel/sched/core.c:7791 __schedule_loop kernel/sched/core.c:7872 [inline] schedule+0xc6/0x240 kernel/sched/core.c:7887 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285 rcu_barrier+0x4d/0x530 kernel/rcu/tree.c:4589 netdev_run_todo+0x10e/0xcb0 net/core/dev.c:10868 rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152 tun_detach drivers/net/tun.c:704 [inline] tun_chr_close+0xc5/0x150 drivers/net/tun.c:3517 __fput+0x1fe/0xa00 fs/file_table.c:429 ____fput+0x20/0x30 fs/file_table.c:457 task_work_run+0x1e3/0x250 kernel/task_work.c:240 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x9bc/0x2630 kernel/exit.c:953 do_group_exit+0x22a/0x300 kernel/exit.c:1095 get_signal+0x139d/0x14f0 kernel/signal.c:2933 arch_do_signal_or_restart+0x96/0x720 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x58/0xb0 kernel/entry/common.c:218 do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f20495c14a5 RSP: 002b:00007f204a3e7f80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007f20497c6090 RCX: 00007f20495c14a5 RDX: 00007f204a3e7fc0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f2049611e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007f20497c6128 R14: 00007f20497c6090 R15: 00007ffe7b961708 INFO: task syz.3.303:1288 blocked for more than 125 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.303 state:D stack:0 pid:1288 tgid:1287 ppid:291 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5945 [inline] __schedule+0x1322/0x1df0 kernel/sched/core.c:7791 __schedule_loop kernel/sched/core.c:7872 [inline] schedule+0xc6/0x240 kernel/sched/core.c:7887 schedule_timeout+0xb2/0x3a0 kernel/time/timer.c:2595 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common+0x359/0x630 kernel/sched/completion.c:127 wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148 rcu_barrier+0x415/0x530 kernel/rcu/tree.c:4657 netdev_run_todo+0x10e/0xcb0 net/core/dev.c:10868 rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152 tun_detach drivers/net/tun.c:704 [inline] tun_chr_close+0xc5/0x150 drivers/net/tun.c:3517 __fput+0x1fe/0xa00 fs/file_table.c:429 ____fput+0x20/0x30 fs/file_table.c:457 task_work_run+0x1e3/0x250 kernel/task_work.c:240 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x9bc/0x2630 kernel/exit.c:953 do_group_exit+0x22a/0x300 kernel/exit.c:1095 get_signal+0x139d/0x14f0 kernel/signal.c:2933 arch_do_signal_or_restart+0x96/0x720 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x58/0xb0 kernel/entry/common.c:218 do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f204958ebe9 RSP: 002b:00007f204a409038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 00007f20497c5fa0 RCX: 00007f204958ebe9 RDX: 0000200000000040 RSI: 0000000000008914 RDI: 0000000000000006 RBP: 00007f2049611e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f20497c6038 R14: 00007f20497c5fa0 R15: 00007ffe7b961708 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 3f7d833acb9715dc4d925f14855ea176aa3f9a02 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120 dump_stack+0x19/0x20 lib/dump_stack.c:129 nmi_cpu_backtrace+0x2bf/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+0xd8f/0xed0 kernel/hung_task.c:423 kthread+0x2c7/0x370 kernel/kthread.c:389 ret_from_fork+0x64/0xa0 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: 1322 Comm: syz-executor Not tainted syzkaller #0 3f7d833acb9715dc4d925f14855ea176aa3f9a02 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:_compound_head include/linux/page-flags.h:253 [inline] RIP: 0010:copy_present_ptes mm/memory.c:999 [inline] RIP: 0010:copy_pte_range mm/memory.c:1181 [inline] RIP: 0010:copy_pmd_range mm/memory.c:1269 [inline] RIP: 0010:copy_pud_range mm/memory.c:1306 [inline] RIP: 0010:copy_p4d_range mm/memory.c:1330 [inline] RIP: 0010:copy_page_range+0xff5/0x3920 mm/memory.c:1424 Code: 4c 89 e0 48 c1 e8 03 48 89 84 24 d8 00 00 00 42 80 3c 30 00 74 08 4c 89 e7 e8 87 02 10 00 4c 89 a4 24 40 01 00 00 4d 8b 24 24 <44> 89 e6 83 e6 01 31 ff e8 4e df b9 ff 41 f6 c4 01 0f 85 c2 08 00 RSP: 0018:ffffc9000fd1f580 EFLAGS: 00000246 RAX: 1ffffd4000c12461 RBX: ffffea0006092300 RCX: ffff888130f69300 RDX: 0000000000000004 RSI: 000000000023ffff RDI: 000000000018248c RBP: ffffc9000fd1f910 R08: ffffea0006092007 R09: 1ffffd4000c12400 R10: dffffc0000000000 R11: fffff94000c12401 R12: 0000000000000000 R13: 800000018248c027 R14: dffffc0000000000 R15: ffff88817ac4eab8 FS: 000055559187e500(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f41cecf7d60 CR3: 000000017e8c2000 CR4: 00000000003526b0 Call Trace: dup_mmap kernel/fork.c:739 [inline] dup_mm kernel/fork.c:1694 [inline] copy_mm+0x103e/0x1cb0 kernel/fork.c:1746 copy_process+0x123c/0x3220 kernel/fork.c:2406 kernel_clone+0x23f/0x830 kernel/fork.c:2819 __do_sys_clone kernel/fork.c:2964 [inline] __se_sys_clone kernel/fork.c:2948 [inline] __x64_sys_clone+0x18c/0x1f0 kernel/fork.c:2948 x64_sys_call+0x2b3c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:57 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f326f185453 Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00 RSP: 002b:00007ffdcbb51758 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f326f185453 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 000055559187e7d0 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000 net_ratelimit: 95601 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on ªªªªª$ with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on ªªªªª$ with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on ªªªªª$ with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on ªªªªª$ with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on ªªªªª$ with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:42:dd:4e:fe:c9:e1, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)