INFO: task syz.2.1317:8209 blocked for more than 430 seconds. Not tainted 6.16.0-rc1-syzkaller-g306e57988197 #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.1317 state:D stack:0 pid:8209 tgid:8208 ppid:7011 task_flags:0x40044c flags:0x00000004 Call Trace: [] context_switch kernel/sched/core.c:5396 [inline] [] __schedule+0x1022/0x4094 kernel/sched/core.c:6785 [] __schedule_loop kernel/sched/core.c:6863 [inline] [] schedule+0xc4/0x35e kernel/sched/core.c:6878 [] schedule_timeout+0x1c6/0x2ae kernel/time/sleep_timeout.c:75 [] do_wait_for_common kernel/sched/completion.c:95 [inline] [] __wait_for_common+0x1d2/0x3e8 kernel/sched/completion.c:116 [] wait_for_common kernel/sched/completion.c:127 [inline] [] wait_for_completion+0x1a/0x22 kernel/sched/completion.c:148 [] rcu_barrier+0x2dc/0x6cc kernel/rcu/tree.c:3850 [] netdev_run_todo+0x294/0x10b4 net/core/dev.c:11376 [] rtnl_unlock+0x14/0x1c net/core/rtnetlink.c:157 [] tun_detach drivers/net/tun.c:639 [inline] [] tun_chr_close+0xde/0x230 drivers/net/tun.c:3396 [] __fput+0x382/0xa8c fs/file_table.c:465 [] ____fput+0x1c/0x26 fs/file_table.c:493 [] task_work_run+0x16a/0x25e kernel/task_work.c:227 [] exit_task_work include/linux/task_work.h:40 [inline] [] do_exit+0x844/0x28ca kernel/exit.c:955 [] do_group_exit+0xd4/0x26c kernel/exit.c:1104 [] get_signal+0x207c/0x22fc kernel/signal.c:3034 [] arch_do_signal_or_restart+0x5d8/0x24c6 arch/riscv/kernel/signal.c:431 [] exit_to_user_mode_loop+0x90/0x134 kernel/entry/common.c:111 [] exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] [] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] [] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] [] do_trap_ecall_u+0x3f0/0x530 arch/riscv/kernel/traps.c:355 [] handle_exception+0x146/0x152 arch/riscv/kernel/entry.S:197 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff883dc420 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2a/0x1a0 kernel/locking/lockdep.c:6766 1 lock held by syslogd/2987: 1 lock held by klogd/2991: 2 locks held by getty/3143: #0: ffffaf80184730a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3a/0x46 drivers/tty/tty_ldsem.c:340 #1: ffff8f800008b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x3e4/0x12b6 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/3172: 2 locks held by kworker/0:1/6125: 4 locks held by kworker/0:0/6607: 2 locks held by kworker/u10:3/7103: 2 locks held by kworker/0:2/7718: 3 locks held by kworker/u10:0/7962: 2 locks held by kworker/0:5/8140: 2 locks held by kworker/0:6/8202: 2 locks held by kworker/1:4/8204: 1 lock held by syz.2.1317/8209: #0: ffffffff883ec640 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x56/0x6cc kernel/rcu/tree.c:3782 2 locks held by kworker/0:7/8212: 3 locks held by syz-executor/8225: 2 locks held by kworker/0:9/8231: 2 locks held by kworker/0:11/8254: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted 6.16.0-rc1-syzkaller-g306e57988197 #0 PREEMPT Hardware name: riscv-virtio,qemu (DT) Call Trace: [] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:132 [] show_stack+0x30/0x3c arch/riscv/kernel/stacktrace.c:138 [] __dump_stack lib/dump_stack.c:94 [inline] [] dump_stack_lvl+0x12e/0x1a6 lib/dump_stack.c:120 [] dump_stack+0x1c/0x24 lib/dump_stack.c:129 [] nmi_cpu_backtrace+0x3b0/0x3b2 lib/nmi_backtrace.c:113 [] nmi_trigger_cpumask_backtrace+0x2b6/0x458 lib/nmi_backtrace.c:62 [] arch_trigger_cpumask_backtrace+0x2c/0x3c arch/riscv/kernel/smp.c:350 [] trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] [] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] [] watchdog+0xcf2/0x11de kernel/hung_task.c:470 [] kthread+0x39c/0x7d4 kernel/kthread.c:464 [] ret_from_fork_kernel+0x2a/0xbb2 arch/riscv/kernel/process.c:214 [] ret_from_fork_kernel_asm+0x16/0x18 arch/riscv/kernel/entry.S:327 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6607 Comm: kworker/0:0 Not tainted 6.16.0-rc1-syzkaller-g306e57988197 #0 PREEMPT Hardware name: riscv-virtio,qemu (DT) Workqueue: wg-crypt-wg0 wg_packet_tx_worker epc : walk_stackframe+0x150/0x44e arch/riscv/kernel/stacktrace.c:67 ra : walk_stackframe+0x150/0x44e arch/riscv/kernel/stacktrace.c:65 epc : ffffffff800784fe ra : ffffffff800784fe sp : ffff8f8000006710 gp : ffffffff89c7e9c0 tp : ffffaf8019b71a40 t0 : ffff8f8000006a60 t1 : 0000000000000001 t2 : fffffffff2f20000 s0 : ffff8f8000006790 s1 : ffff8f8000006aa0 a0 : 0000000000000007 a1 : 0000000000000000 a2 : 0000000000f00000 a3 : ffffffff800784fe a4 : 0000000000000000 a5 : ffffaf8019b71a40 a6 : 0000000000f00000 a7 : ffffffff8572a352 s2 : 0000000000000000 s3 : 0000000000000003 s4 : 0000000000000000 s5 : dfffffff00000000 s6 : ffffffff80af29fc s7 : ffff8f8000006a90 s8 : dfffffff00000000 s9 : 0000000000007fff s10: ffffffff86324f84 s11: 0000000000000007 t3 : 81987a7b00000000 t4 : 0000000000001fff t5 : 00000000000000c8 t6 : 0000000000000002 status: 0000000200000120 badaddr: 0000000000000000 cause: 8000000000000001 [] walk_stackframe+0x150/0x44e arch/riscv/kernel/stacktrace.c:65 [] arch_stack_walk+0x1c/0x26 arch/riscv/kernel/stacktrace.c:165 [] stack_trace_save+0xa0/0xd2 kernel/stacktrace.c:122 [] kasan_save_stack+0x3e/0x6a mm/kasan/common.c:47 [] kasan_save_track+0x16/0x28 mm/kasan/common.c:68 [] kasan_save_alloc_info+0x30/0x3e mm/kasan/generic.c:562 [] unpoison_slab_object mm/kasan/common.c:319 [inline] [] __kasan_slab_alloc+0x7c/0x82 mm/kasan/common.c:345 [] kasan_slab_alloc include/linux/kasan.h:250 [inline] [] slab_post_alloc_hook mm/slub.c:4148 [inline] [] slab_alloc_node mm/slub.c:4197 [inline] [] kmem_cache_alloc_noprof+0x104/0x3d0 mm/slub.c:4204 [] dst_alloc+0x94/0x174 net/core/dst.c:89 [] rt_dst_alloc+0x3a/0x340 net/ipv4/route.c:1642 [] __mkroute_output net/ipv4/route.c:2643 [inline] [] ip_route_output_key_hash_rcu+0x822/0x29f8 net/ipv4/route.c:2864 [] ip_route_output_key_hash+0x158/0x31c net/ipv4/route.c:2694 [] __ip_route_output_key include/net/route.h:169 [inline] [] ip_route_output_flow+0x2a/0x142 net/ipv4/route.c:2921 [] ip_route_output_key include/net/route.h:179 [inline] [] ip_route_me_harder+0x52e/0x11a6 net/ipv4/netfilter.c:53 [] synproxy_send_tcp.isra.0+0x2be/0x5d2 net/netfilter/nf_synproxy_core.c:431 [] synproxy_send_client_synack+0x6dc/0x8be net/netfilter/nf_synproxy_core.c:484 [] nft_synproxy_eval_v4 net/netfilter/nft_synproxy.c:59 [inline] [] nft_synproxy_do_eval+0x8ac/0xa52 net/netfilter/nft_synproxy.c:141 [] nft_synproxy_eval+0x28/0x36 net/netfilter/nft_synproxy.c:247 [] expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline] [] nft_do_chain+0x328/0x1598 net/netfilter/nf_tables_core.c:285 [] nft_do_chain_inet+0x180/0x316 net/netfilter/nft_chain_filter.c:161 [] nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline] [] nf_hook_slow+0xb8/0x1ec net/netfilter/core.c:623 [] nf_hook include/linux/netfilter.h:272 [inline] [] NF_HOOK include/linux/netfilter.h:315 [inline] [] ip_local_deliver+0x2ea/0x568 net/ipv4/ip_input.c:254 [] dst_input include/net/dst.h:469 [inline] [] ip_rcv_finish+0x1b0/0x2d2 net/ipv4/ip_input.c:447 [] NF_HOOK include/linux/netfilter.h:317 [inline] [] NF_HOOK include/linux/netfilter.h:311 [inline] [] ip_rcv+0xd6/0x44e net/ipv4/ip_input.c:567 [] __netif_receive_skb_one_core+0x106/0x16e net/core/dev.c:5977 [] __netif_receive_skb+0x2c/0x144 net/core/dev.c:6090 [] process_backlog+0x4f6/0x1cb0 net/core/dev.c:6442 [] __napi_poll.constprop.0+0xaa/0x4ba net/core/dev.c:7414 [] napi_poll net/core/dev.c:7478 [inline] [] net_rx_action+0xad4/0xefc net/core/dev.c:7605 [] handle_softirqs+0x4b2/0x132e kernel/softirq.c:579 [] __do_softirq+0x12/0x1a kernel/softirq.c:613 [] ___do_softirq+0x18/0x20 arch/riscv/kernel/irq.c:85 [] call_on_irq_stack+0x32/0x40 arch/riscv/kernel/entry.S:360