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: 17838 Comm: syz-executor.3 Not tainted 5.14.0-rc5-next-20210812-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 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:ffffc90000007cf8 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000100 RDX: 00000000000000b2 RSI: ffffffff83d2005d RDI: 0000000000000590 RBP: ffff88801b10cc00 R08: 0000000000000003 R09: ffff88801b10cd83 R10: ffffffff83d20052 R11: 0000000000000000 R12: 0000000000000003 R13: 0000000000000000 R14: ffff888145fe6d80 R15: ffff88801b10ccd0 FS: 00007f1866db0700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000014a53ad CR3: 000000001ac23000 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 do_softirq.part.0+0xde/0x130 kernel/softirq.c:459 do_softirq kernel/softirq.c:451 [inline] __local_bh_enable_ip+0x102/0x120 kernel/softirq.c:383 local_bh_enable include/linux/bottom_half.h:32 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:757 [inline] ip6_finish_output2+0x765/0x1500 net/ipv6/ip6_output.c:127 ip6_fragment+0xa8f/0x2700 net/ipv6/ip6_output.c:965 __ip6_finish_output net/ipv6/ip6_output.c:189 [inline] __ip6_finish_output+0x5fa/0x1050 net/ipv6/ip6_output.c:170 ip6_finish_output+0x32/0x200 net/ipv6/ip6_output.c:201 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x1e4/0x530 net/ipv6/ip6_output.c:224 dst_output include/net/dst.h:450 [inline] ip6_local_out+0xaf/0x1a0 net/ipv6/output_core.c:161 ip6_send_skb+0xb7/0x340 net/ipv6/ip6_output.c:1911 ip6_push_pending_frames+0xdd/0x100 net/ipv6/ip6_output.c:1931 rawv6_push_pending_frames net/ipv6/raw.c:613 [inline] rawv6_sendmsg+0x2b0c/0x3a20 net/ipv6/raw.c:956 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:821 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 __sys_sendto+0x21c/0x320 net/socket.c:2030 __do_sys_sendto net/socket.c:2042 [inline] __se_sys_sendto net/socket.c:2038 [inline] __x64_sys_sendto+0xdd/0x1b0 net/socket.c:2038 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f1866db0188 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665e9 RDX: 00000000000053e8 RSI: 0000000020000000 RDI: 0000000000000004 RBP: 00000000004bfcc4 R08: 0000000020000180 R09: 000000000000001c R10: 00000000ff000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007fff667a42bf R14: 00007f1866db0300 R15: 0000000000022000 Modules linked in: ---[ end trace be4ce0c12ea697ec ]--- 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:ffffc90000007cf8 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000100 RDX: 00000000000000b2 RSI: ffffffff83d2005d RDI: 0000000000000590 RBP: ffff88801b10cc00 R08: 0000000000000003 R09: ffff88801b10cd83 R10: ffffffff83d20052 R11: 0000000000000000 R12: 0000000000000003 R13: 0000000000000000 R14: ffff888145fe6d80 R15: ffff88801b10ccd0 FS: 00007f1866db0700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000014a53ad CR3: 000000001ac23000 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)