syzbot


kernel BUG in fou_build_udp

Status: fixed on 2023/06/08 14:41
Subsystems: net
[Documentation on labels]
Fix commit: c88f8d5cd95f UPSTREAM: sit: update dev->needed_headroom in ipip6_tunnel_bind_dev()
First crash: 348d, last: 348d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 kernel BUG at net/core/skbuff.c:LINE! C unreliable 494 596d 1815d 0/1 upstream: reported C repro on 2019/04/27 20:12
upstream kernel BUG at net/core/skbuff.c:LINE! (3) C done 4399 1149d 2265d 19/26 fixed on 2021/03/10 01:48
linux-4.14 kernel BUG at net/core/skbuff.c:LINE! C 3066 411d 1831d 0/1 upstream: reported C repro on 2019/04/12 15:43
upstream kernel BUG in llc_sap_action_send_xid_c net C error 61 889d 1102d 20/26 fixed on 2021/11/10 00:50
upstream kernel BUG in pskb_expand_head net C done 1600 432d 883d 22/26 fixed on 2023/02/25 08:02

Sample crash report:
skbuff: skb_under_panic: text:ffffffff88aeef20 len:48 put:8 head:ffff88801f654c00 data:ffff88801f654bfc tail:0x2c end:0x140 dev:sit1
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:200!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 4997 Comm: syz-executor258 Not tainted 6.3.0-syzkaller-12964-g89b7fd5d7f3c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
RIP: 0010:skb_panic+0x152/0x1d0 net/core/skbuff.c:200
Code: 0f b6 04 01 84 c0 74 04 3c 03 7e 20 8b 4b 70 41 56 45 89 e8 48 c7 c7 40 c9 5d 8b 41 57 56 48 89 ee 52 4c 89 e2 e8 3e 04 61 f9 <0f> 0b 4c 89 4c 24 10 48 89 54 24 08 48 89 34 24 e8 49 ec cf f9 4c
RSP: 0018:ffffc900039beae8 EFLAGS: 00010282
RAX: 0000000000000084 RBX: ffff88807624adc0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8168cf6c RDI: 0000000000000005
RBP: ffffffff8b5dd760 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000200 R11: 0000000000000001 R12: ffffffff88aeef20
R13: 0000000000000008 R14: ffff888021056000 R15: 0000000000000140
FS:  0000555556c60300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbe19f5ba60 CR3: 0000000076258000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 skb_under_panic net/core/skbuff.c:210 [inline]
 skb_push+0xc8/0xe0 net/core/skbuff.c:2401
 fou_build_udp+0x30/0x370 net/ipv4/fou_core.c:1021
 gue_build_header+0xfb/0x150 net/ipv4/fou_core.c:1064
 ip_tunnel_encap include/net/ip_tunnels.h:398 [inline]
 ip_tunnel_encap include/net/ip_tunnels.h:382 [inline]
 ip_tunnel_xmit+0x67a/0x3170 net/ipv4/ip_tunnel.c:753
 sit_tunnel_xmit__.isra.0+0xe7/0x150 net/ipv6/sit.c:1057
 sit_tunnel_xmit+0xf73/0x2860 net/ipv6/sit.c:1073
 __netdev_start_xmit include/linux/netdevice.h:4915 [inline]
 netdev_start_xmit include/linux/netdevice.h:4929 [inline]
 xmit_one net/core/dev.c:3578 [inline]
 dev_hard_start_xmit+0x187/0x700 net/core/dev.c:3594
 __dev_queue_xmit+0x2be2/0x3b10 net/core/dev.c:4244
 dev_queue_xmit include/linux/netdevice.h:3085 [inline]
 neigh_connected_output+0x3c2/0x550 net/core/neighbour.c:1581
 neigh_output include/net/neighbour.h:544 [inline]
 ip_finish_output2+0x778/0x22b0 net/ipv4/ip_output.c:229
 __ip_finish_output net/ipv4/ip_output.c:307 [inline]
 __ip_finish_output+0x396/0x650 net/ipv4/ip_output.c:289
 ip_finish_output+0x31/0x280 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:292 [inline]
 ip_output+0x1a3/0x320 net/ipv4/ip_output.c:431
 dst_output include/net/dst.h:458 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 ip_send_skb+0xd8/0x260 net/ipv4/ip_output.c:1597
 udp_send_skb+0x73a/0x14a0 net/ipv4/udp.c:978
 udp_sendmsg+0x1b86/0x27e0 net/ipv4/udp.c:1265
 udpv6_sendmsg+0x180a/0x2d50 net/ipv6/udp.c:1401
 inet6_sendmsg+0x9d/0xe0 net/ipv6/af_inet6.c:651
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg+0xde/0x190 net/socket.c:747
 ____sys_sendmsg+0x334/0x900 net/socket.c:2503
 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2557
 __sys_sendmmsg+0x18f/0x460 net/socket.c:2643
 __do_sys_sendmmsg net/socket.c:2672 [inline]
 __se_sys_sendmmsg net/socket.c:2669 [inline]
 __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2669
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f8ad2d73139
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 14 00 00 90 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc3813a128 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8ad2d73139
RDX: 0000000000000001 RSI: 00000000200017c0 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffc3813a2c8 R09: 00007ffc3813a2c8
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8ad2d369c0
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:skb_panic+0x152/0x1d0 net/core/skbuff.c:200
Code: 0f b6 04 01 84 c0 74 04 3c 03 7e 20 8b 4b 70 41 56 45 89 e8 48 c7 c7 40 c9 5d 8b 41 57 56 48 89 ee 52 4c 89 e2 e8 3e 04 61 f9 <0f> 0b 4c 89 4c 24 10 48 89 54 24 08 48 89 34 24 e8 49 ec cf f9 4c
RSP: 0018:ffffc900039beae8 EFLAGS: 00010282
RAX: 0000000000000084 RBX: ffff88807624adc0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8168cf6c RDI: 0000000000000005
RBP: ffffffff8b5dd760 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000200 R11: 0000000000000001 R12: ffffffff88aeef20
R13: 0000000000000008 R14: ffff888021056000 R15: 0000000000000140
FS:  0000555556c60300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbe19f5ba60 CR3: 0000000076258000 CR4: 0000000000350ef0

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/05/04 03:52 upstream 89b7fd5d7f3c b5918830 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root kernel BUG in fou_build_udp
* Struck through repros no longer work on HEAD.