general protection fault, probably for non-canonical address 0xdffffc00000000b2: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000590-0x0000000000000597] CPU: 0 PID: 1134 Comm: kworker/u4:4 Not tainted 5.14.0-rc5-next-20210816-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:latency_exceeded block/blk-wbt.c:237 [inline] RIP: 0010:wb_timer_fn+0x149/0x1740 block/blk-wbt.c:360 Code: 03 80 3c 02 00 0f 85 68 13 00 00 48 8b 9b c8 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d bb 90 05 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 35 13 00 00 48 8b 9b 90 05 00 00 48 b8 00 00 00 RSP: 0018:ffffc90000007cd8 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000100 RDX: 00000000000000b2 RSI: ffffffff83d225bd RDI: 0000000000000590 RBP: ffff88801b5a1400 R08: 0000000000000003 R09: ffff88801b5a1583 R10: ffffffff83d225b2 R11: 0000000000000000 R12: 0000000000000003 R13: 0000000000000000 R14: ffff8881465caa80 R15: ffff88801b5a14d0 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020123000 CR3: 000000008fd20000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 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:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 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:__preempt_count_add arch/x86/include/asm/preempt.h:80 [inline] RIP: 0010:rcu_is_watching+0x2/0xc0 kernel/rcu/tree.c:1120 Code: ff ff e8 f1 f1 59 00 e9 e6 fd ff ff 4c 89 ff e8 e4 f1 59 00 e9 1a ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 55 53 <65> ff 05 07 6d a0 7e e8 22 83 ce 07 48 c7 c3 48 2a 03 00 83 f8 07 RSP: 0018:ffffc9000513fb38 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000007cb1 RCX: 0000000000000000 RDX: ffff88801cc1b900 RSI: ffffffff879c3809 RDI: 0000000000000003 RBP: 0000000000007cb1 R08: 0000000000007cb1 R09: 0000000000000001 R10: ffffffff879c37fb R11: 0000000000000000 R12: ffffffff8d3b5d00 R13: ffffc9000513fcb0 R14: 000000000000000a R15: dffffc0000000000 rcu_read_unlock include/linux/rcupdate.h:716 [inline] inet_twsk_purge+0x4ce/0x7d0 net/ipv4/inet_timewait_sock.c:299 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:178 cleanup_net+0x4ea/0xb10 net/core/net_namespace.c:595 process_one_work+0x98d/0x1630 kernel/workqueue.c:2275 worker_thread+0x658/0x11f0 kernel/workqueue.c:2421 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Modules linked in: ---[ end trace 94aa7c4026d7ed71 ]--- RIP: 0010:latency_exceeded block/blk-wbt.c:237 [inline] RIP: 0010:wb_timer_fn+0x149/0x1740 block/blk-wbt.c:360 Code: 03 80 3c 02 00 0f 85 68 13 00 00 48 8b 9b c8 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d bb 90 05 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 35 13 00 00 48 8b 9b 90 05 00 00 48 b8 00 00 00 RSP: 0018:ffffc90000007cd8 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000100 RDX: 00000000000000b2 RSI: ffffffff83d225bd RDI: 0000000000000590 RBP: ffff88801b5a1400 R08: 0000000000000003 R09: ffff88801b5a1583 R10: ffffffff83d225b2 R11: 0000000000000000 R12: 0000000000000003 R13: 0000000000000000 R14: ffff8881465caa80 R15: ffff88801b5a14d0 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020123000 CR3: 000000008fd20000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 03 80 3c 02 00 0f add 0xf00023c(%rax),%eax 6: 85 68 13 test %ebp,0x13(%rax) 9: 00 00 add %al,(%rax) b: 48 8b 9b c8 00 00 00 mov 0xc8(%rbx),%rbx 12: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 19: fc ff df 1c: 48 8d bb 90 05 00 00 lea 0x590(%rbx),%rdi 23: 48 89 fa mov %rdi,%rdx 26: 48 c1 ea 03 shr $0x3,%rdx 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2e: 0f 85 35 13 00 00 jne 0x1369 34: 48 8b 9b 90 05 00 00 mov 0x590(%rbx),%rbx 3b: 48 rex.W 3c: b8 .byte 0xb8 3d: 00 00 add %al,(%rax)