Oops: general protection fault, probably for non-canonical address 0xdffffc000000000e: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000070-0x0000000000000077] CPU: 3 UID: 0 PID: 8983 Comm: syz.3.822 Not tainted 6.13.0-rc7-syzkaller-00039-gc3812b15000c #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:skb_segment+0x1940/0x40b0 net/core/skbuff.c:4802 Code: 00 00 fe e9 4f eb ff ff e8 6d 39 94 f8 48 8b 84 24 d0 00 00 00 48 8d 78 70 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 09 3c 03 7f 05 e8 ef e5 f6 f8 48 8b 84 24 d0 RSP: 0018:ffffc90003246808 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000020048 RCX: ffffc90026f62000 RDX: 000000000000000e RSI: ffffffff8905eb33 RDI: 0000000000000070 RBP: ffffc900032469b0 R08: 0000000000000005 R09: 000000000000ffff R10: 000000000000ffff R11: aaaa0aaaaaaaaaaa R12: ffff888028057d40 R13: 000000000001fffe R14: 000000000001fffe R15: 000000000000ffff FS: 00007f795a7956c0(0000) GS:ffff88806a900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000004e70c000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: tcp_gso_segment+0x3ca/0x1940 net/ipv4/tcp_offload.c:176 tcp6_gso_segment net/ipv6/tcpv6_offload.c:184 [inline] tcp6_gso_segment+0x207/0x1570 net/ipv6/tcpv6_offload.c:151 ipv6_gso_segment+0x80b/0x1d90 net/ipv6/ip6_offload.c:152 skb_mac_gso_segment+0x2a6/0x650 net/core/gso.c:53 __skb_gso_segment+0x36e/0x700 net/core/gso.c:124 skb_gso_segment include/net/gso.h:83 [inline] validate_xmit_skb+0x669/0xf90 net/core/dev.c:3707 validate_xmit_skb_list+0xc1/0x130 net/core/dev.c:3757 sch_direct_xmit+0x398/0xc30 net/sched/sch_generic.c:328 qdisc_restart net/sched/sch_generic.c:408 [inline] __qdisc_run+0x53f/0x1a10 net/sched/sch_generic.c:416 __dev_xmit_skb net/core/dev.c:3928 [inline] __dev_queue_xmit+0x2aa4/0x43e0 net/core/dev.c:4432 dev_queue_xmit include/linux/netdevice.h:3168 [inline] neigh_hh_output include/net/neighbour.h:523 [inline] neigh_output include/net/neighbour.h:537 [inline] ip6_finish_output2+0x1801/0x2070 net/ipv6/ip6_output.c:141 __ip6_finish_output net/ipv6/ip6_output.c:215 [inline] ip6_finish_output+0x3f9/0x1360 net/ipv6/ip6_output.c:226 NF_HOOK_COND include/linux/netfilter.h:303 [inline] ip6_output+0x1f8/0x540 net/ipv6/ip6_output.c:247 dst_output include/net/dst.h:450 [inline] NF_HOOK include/linux/netfilter.h:314 [inline] NF_HOOK include/linux/netfilter.h:308 [inline] ip6_xmit+0x1234/0x2130 net/ipv6/ip6_output.c:366 inet6_csk_xmit+0x3ce/0x740 net/ipv6/inet6_connection_sock.c:135 __tcp_transmit_skb+0x1b02/0x3e10 net/ipv4/tcp_output.c:1468 tcp_transmit_skb net/ipv4/tcp_output.c:1486 [inline] tcp_write_xmit+0x12b1/0x8560 net/ipv4/tcp_output.c:2829 __tcp_push_pending_frames+0xaf/0x390 net/ipv4/tcp_output.c:3012 tcp_push_pending_frames include/net/tcp.h:2107 [inline] tcp_data_snd_check net/ipv4/tcp_input.c:5741 [inline] tcp_rcv_established+0x868/0x20d0 net/ipv4/tcp_input.c:6266 tcp_v6_do_rcv+0x897/0x1740 net/ipv6/tcp_ipv6.c:1644 sk_backlog_rcv include/net/sock.h:1121 [inline] __release_sock+0x14c/0x400 net/core/sock.c:3086 __sk_flush_backlog+0x27/0xc0 net/core/sock.c:3106 sk_flush_backlog include/net/sock.h:1184 [inline] tcp_sendmsg_locked+0x2f26/0x3770 net/ipv4/tcp.c:1164 tcp_sendmsg+0x2e/0x50 net/ipv4/tcp.c:1358 inet6_sendmsg+0xb9/0x140 net/ipv6/af_inet6.c:659 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg net/socket.c:726 [inline] __sys_sendto+0x374/0x4f0 net/socket.c:2197 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2200 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7959985d29 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f795a795038 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f7959b76160 RCX: 00007f7959985d29 RDX: ffffffffffffff1d RSI: 00000000200000c0 RDI: 0000000000000009 RBP: 00007f7959a01b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000850 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f7959b76160 R15: 00007ffdfa2d6ed8 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:skb_segment+0x1940/0x40b0 net/core/skbuff.c:4802 Code: 00 00 fe e9 4f eb ff ff e8 6d 39 94 f8 48 8b 84 24 d0 00 00 00 48 8d 78 70 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 09 3c 03 7f 05 e8 ef e5 f6 f8 48 8b 84 24 d0 RSP: 0018:ffffc90003246808 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000020048 RCX: ffffc90026f62000 RDX: 000000000000000e RSI: ffffffff8905eb33 RDI: 0000000000000070 RBP: ffffc900032469b0 R08: 0000000000000005 R09: 000000000000ffff R10: 000000000000ffff R11: aaaa0aaaaaaaaaaa R12: ffff888028057d40 R13: 000000000001fffe R14: 000000000001fffe R15: 000000000000ffff FS: 00007f795a7956c0(0000) GS:ffff88806a900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000004e70c000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 00 fe add %bh,%dh 2: e9 4f eb ff ff jmp 0xffffeb56 7: e8 6d 39 94 f8 call 0xf8943979 c: 48 8b 84 24 d0 00 00 mov 0xd0(%rsp),%rax 13: 00 14: 48 8d 78 70 lea 0x70(%rax),%rdi 18: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 1f: fc ff df 22: 48 89 fa mov %rdi,%rdx 25: 48 c1 ea 03 shr $0x3,%rdx * 29: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax <-- trapping instruction 2d: 84 c0 test %al,%al 2f: 74 09 je 0x3a 31: 3c 03 cmp $0x3,%al 33: 7f 05 jg 0x3a 35: e8 ef e5 f6 f8 call 0xf8f6e629 3a: 48 rex.W 3b: 8b .byte 0x8b 3c: 84 24 d0 test %ah,(%rax,%rdx,8)