------------[ cut here ]------------ WARNING: net/mptcp/subflow.c:1527 at subflow_data_ready+0x40b/0x790 net/mptcp/subflow.c:1527, CPU#2: swapper/2/0 Modules linked in: CPU: 2 UID: 0 PID: 0 Comm: swapper/2 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:subflow_data_ready+0x40b/0x790 net/mptcp/subflow.c:1527 Code: 89 ee e8 e8 32 5b f6 40 84 ed 75 21 e8 9e 38 5b f6 44 89 fe bf 07 00 00 00 e8 31 33 5b f6 41 83 ff 07 74 09 e8 86 38 5b f6 90 <0f> 0b 90 e8 7d 38 5b f6 48 89 df e8 f5 ac ff ff 31 ff 89 c5 89 c6 RSP: 0018:ffffc900006484c8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88802d684240 RCX: ffffffff8b63ae2f RDX: ffff88801decc980 RSI: ffffffff8b63ae3a RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000007 R10: 0000000000000004 R11: ffff88801decd4b0 R12: ffff88803a190c80 R13: 1ffff920000c9099 R14: ffff888033928800 R15: 0000000000000004 FS: 0000000000000000(0000) GS:ffff8880d6af5000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffcb2e46fc0 CR3: 000000000e184000 CR4: 0000000000352ef0 Call Trace: tcp_data_ready+0x114/0x5a0 net/ipv4/tcp_input.c:5371 tcp_data_queue+0x1ac2/0x4ff0 net/ipv4/tcp_input.c:5461 tcp_rcv_state_process+0xfb6/0x6540 net/ipv4/tcp_input.c:7185 tcp_v6_do_rcv+0x7b8/0x1dc0 net/ipv6/tcp_ipv6.c:1630 tcp_v6_rcv+0x2ab5/0x48f0 net/ipv6/tcp_ipv6.c:1877 ip6_protocol_deliver_rcu+0x188/0x1520 net/ipv6/ip6_input.c:438 ip6_input_finish+0x1e4/0x4b0 net/ipv6/ip6_input.c:489 NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] ip6_input+0x105/0x2f0 net/ipv6/ip6_input.c:500 dst_input include/net/dst.h:474 [inline] ip6_rcv_finish net/ipv6/ip6_input.c:79 [inline] NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] ipv6_rcv+0x264/0x650 net/ipv6/ip6_input.c:311 __netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:6137 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6250 process_backlog+0x4a2/0x1650 net/core/dev.c:6602 __napi_poll.constprop.0+0xb3/0x540 net/core/dev.c:7666 napi_poll net/core/dev.c:7729 [inline] net_rx_action+0x9f9/0xfa0 net/core/dev.c:7881 handle_softirqs+0x219/0x950 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: b6 5f 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d 13 39 12 00 fb f4 cc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000187de8 EFLAGS: 00000286 RAX: 0000000000097673 RBX: 0000000000000002 RCX: ffffffff8b7826d9 RDX: 0000000000000000 RSI: ffffffff8dacdf23 RDI: ffffffff8bf2b400 RBP: ffffed1003bd9930 R08: 0000000000000001 R09: ffffed100d4c673d R10: ffff88806a6339eb R11: ffff88801decd4b0 R12: 0000000000000002 R13: ffff88801decc980 R14: ffffffff9088b4d0 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x38d/0x510 kernel/sched/idle.c:332 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430 start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x148 ---------------- Code disassembly (best guess): 0: b6 5f mov $0x5f,%dh 2: 02 c3 add %bl,%al 4: cc int3 5: cc int3 6: cc int3 7: cc int3 8: 0f 1f 00 nopl (%rax) b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: 90 nop 1b: f3 0f 1e fa endbr64 1f: eb 07 jmp 0x28 21: 0f 00 2d 13 39 12 00 verw 0x123913(%rip) # 0x12393b 28: fb sti 29: f4 hlt * 2a: e9 cc 35 03 00 jmp 0x335fb <-- trapping instruction 2f: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 36: 00 00 00 39: 66 90 xchg %ax,%ax 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: 90 nop