BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 75ba5067 P4D 75ba5067 PUD 1df58067 PMD 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 1 PID: 2380 Comm: kworker/u4:5 Not tainted 5.17.0-rc7-syzkaller-02443-gd96657dc9238 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:0x0 Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. RSP: 0018:ffffc900001d0a60 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffff88801d82a010 RCX: 0000000000000100 RDX: 1ffff11003b05403 RSI: ffff88806a645dc0 RDI: ffff88805121d400 RBP: ffff88805121d400 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff87bb8a27 R11: 0000000000000000 R12: ffff88806a645dc0 R13: 0000000000000000 R14: ffff88805121db58 R15: ffff888077a4e12c FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 000000007d10d000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __tcp_transmit_skb+0x1098/0x38b0 net/ipv4/tcp_output.c:1371 tcp_transmit_skb net/ipv4/tcp_output.c:1420 [inline] tcp_xmit_probe_skb+0x28c/0x320 net/ipv4/tcp_output.c:4006 tcp_write_wakeup+0x1bd/0x610 net/ipv4/tcp_output.c:4059 tcp_send_probe0+0x44/0x560 net/ipv4/tcp_output.c:4074 tcp_probe_timer net/ipv4/tcp_timer.c:398 [inline] tcp_write_timer_handler+0x9ed/0xbc0 net/ipv4/tcp_timer.c:626 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:642 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x67c/0xa30 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__local_bh_enable_ip+0xa8/0x120 kernel/softirq.c:390 Code: 1d 9d 28 bb 7e 65 8b 05 96 28 bb 7e a9 00 ff ff 00 74 45 bf 01 00 00 00 e8 95 7a 09 00 e8 40 b7 37 00 fb 65 8b 05 78 28 bb 7e <85> c0 74 58 5b 5d c3 65 8b 05 c6 2f bb 7e 85 c0 75 a2 0f 0b eb 9e RSP: 0018:ffffc9000b047bd8 EFLAGS: 00000202 RAX: 0000000080000000 RBX: 00000000fffffe00 RCX: 1ffffffff1fc0cfe RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffff87c03de1 R08: 0000000000000001 R09: ffffffff8fe0194f R10: 0000000000000001 R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000002 R14: 0000000000000000 R15: ffff888017a06f08 spin_unlock_bh include/linux/spinlock.h:394 [inline] tcp_metrics_flush_all+0x271/0x350 net/ipv4/tcp_metrics.c:898 ops_exit_list+0x125/0x170 net/core/net_namespace.c:167 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:594 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Modules linked in: CR2: 0000000000000000 ---[ end trace 0000000000000000 ]--- RIP: 0010:0x0 Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. RSP: 0018:ffffc900001d0a60 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffff88801d82a010 RCX: 0000000000000100 RDX: 1ffff11003b05403 RSI: ffff88806a645dc0 RDI: ffff88805121d400 RBP: ffff88805121d400 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff87bb8a27 R11: 0000000000000000 R12: ffff88806a645dc0 R13: 0000000000000000 R14: ffff88805121db58 R15: ffff888077a4e12c FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 000000007d10d000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 1d 9d 28 bb 7e sbb $0x7ebb289d,%eax 5: 65 8b 05 96 28 bb 7e mov %gs:0x7ebb2896(%rip),%eax # 0x7ebb28a2 c: a9 00 ff ff 00 test $0xffff00,%eax 11: 74 45 je 0x58 13: bf 01 00 00 00 mov $0x1,%edi 18: e8 95 7a 09 00 callq 0x97ab2 1d: e8 40 b7 37 00 callq 0x37b762 22: fb sti 23: 65 8b 05 78 28 bb 7e mov %gs:0x7ebb2878(%rip),%eax # 0x7ebb28a2 * 2a: 85 c0 test %eax,%eax <-- trapping instruction 2c: 74 58 je 0x86 2e: 5b pop %rbx 2f: 5d pop %rbp 30: c3 retq 31: 65 8b 05 c6 2f bb 7e mov %gs:0x7ebb2fc6(%rip),%eax # 0x7ebb2ffe 38: 85 c0 test %eax,%eax 3a: 75 a2 jne 0xffffffde 3c: 0f 0b ud2 3e: eb 9e jmp 0xffffffde