syzbot


KCSAN: data-race in ip6_tnl_xmit / ip6_tnl_xmit (5)

Status: auto-closed as invalid on 2022/04/16 19:07
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 365d, last: 327d
similar bugs (5):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in ip6_tnl_xmit / ip6_tnl_xmit (6) 1 233d 233d 0/24 auto-closed as invalid on 2022/07/19 20:28
upstream KCSAN: data-race in ip6_tnl_xmit / ip6_tnl_xmit 3 1191d 1195d 0/24 closed as invalid on 2019/11/19 13:24
upstream KCSAN: data-race in ip6_tnl_xmit / ip6_tnl_xmit (4) 1 442d 442d 0/24 auto-closed as invalid on 2021/12/22 23:42
upstream KCSAN: data-race in ip6_tnl_xmit / ip6_tnl_xmit (2) 1 862d 862d 0/24 auto-closed as invalid on 2020/10/29 08:32
upstream KCSAN: data-race in ip6_tnl_xmit / ip6_tnl_xmit (3) 1 722d 722d 0/24 auto-closed as invalid on 2021/03/18 08:19

Sample crash report:
==================================================================
BUG: KCSAN: data-race in ip6_tnl_xmit / ip6_tnl_xmit

read to 0xffff88813308f1b8 of 8 bytes by task 31142 on cpu 0:
 ip6_tnl_xmit+0x56c/0x1620 net/ipv6/ip6_tunnel.c:1264
 ipxip6_tnl_xmit net/ipv6/ip6_tunnel.c:1381 [inline]
 ip6_tnl_start_xmit+0x943/0xa90 net/ipv6/ip6_tunnel.c:1430
 __netdev_start_xmit include/linux/netdevice.h:4685 [inline]
 netdev_start_xmit include/linux/netdevice.h:4699 [inline]
 xmit_one+0x105/0x2f0 net/core/dev.c:3473
 dev_hard_start_xmit net/core/dev.c:3489 [inline]
 __dev_queue_xmit+0x86d/0xfa0 net/core/dev.c:4116
 dev_queue_xmit+0x13/0x20 net/core/dev.c:4149
 neigh_connected_output+0x264/0x2a0 net/core/neighbour.c:1557
 neigh_output include/net/neighbour.h:549 [inline]
 ip6_finish_output2+0x9ce/0xbe0 net/ipv6/ip6_output.c:126
 __ip6_finish_output net/ipv6/ip6_output.c:191 [inline]
 ip6_finish_output+0x446/0x4c0 net/ipv6/ip6_output.c:201
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip6_output+0x10e/0x210 net/ipv6/ip6_output.c:224
 dst_output include/net/dst.h:451 [inline]
 ip6_local_out+0x60/0x80 net/ipv6/output_core.c:161
 ip6_send_skb net/ipv6/ip6_output.c:1915 [inline]
 ip6_push_pending_frames+0xb6/0x170 net/ipv6/ip6_output.c:1935
 rawv6_push_pending_frames net/ipv6/raw.c:613 [inline]
 rawv6_sendmsg+0x1341/0x14a0 net/ipv6/raw.c:956
 inet_sendmsg+0x5f/0x80 net/ipv4/af_inet.c:819
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg net/socket.c:725 [inline]
 ____sys_sendmsg+0x39a/0x510 net/socket.c:2413
 ___sys_sendmsg net/socket.c:2467 [inline]
 __sys_sendmmsg+0x267/0x4c0 net/socket.c:2553
 __do_sys_sendmmsg net/socket.c:2582 [inline]
 __se_sys_sendmmsg net/socket.c:2579 [inline]
 __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2579
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

write to 0xffff88813308f1b8 of 8 bytes by task 31140 on cpu 1:
 ip6_tnl_xmit+0x57e/0x1620 net/ipv6/ip6_tunnel.c:1264
 ipxip6_tnl_xmit net/ipv6/ip6_tunnel.c:1381 [inline]
 ip6_tnl_start_xmit+0x943/0xa90 net/ipv6/ip6_tunnel.c:1430
 __netdev_start_xmit include/linux/netdevice.h:4685 [inline]
 netdev_start_xmit include/linux/netdevice.h:4699 [inline]
 xmit_one+0x105/0x2f0 net/core/dev.c:3473
 dev_hard_start_xmit net/core/dev.c:3489 [inline]
 __dev_queue_xmit+0x86d/0xfa0 net/core/dev.c:4116
 dev_queue_xmit+0x13/0x20 net/core/dev.c:4149
 neigh_connected_output+0x264/0x2a0 net/core/neighbour.c:1557
 neigh_output include/net/neighbour.h:549 [inline]
 ip6_finish_output2+0x9ce/0xbe0 net/ipv6/ip6_output.c:126
 __ip6_finish_output net/ipv6/ip6_output.c:191 [inline]
 ip6_finish_output+0x446/0x4c0 net/ipv6/ip6_output.c:201
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip6_output+0x10e/0x210 net/ipv6/ip6_output.c:224
 dst_output include/net/dst.h:451 [inline]
 ip6_local_out+0x60/0x80 net/ipv6/output_core.c:161
 ip6_send_skb net/ipv6/ip6_output.c:1915 [inline]
 ip6_push_pending_frames+0xb6/0x170 net/ipv6/ip6_output.c:1935
 rawv6_push_pending_frames net/ipv6/raw.c:613 [inline]
 rawv6_sendmsg+0x1341/0x14a0 net/ipv6/raw.c:956
 inet_sendmsg+0x5f/0x80 net/ipv4/af_inet.c:819
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg net/socket.c:725 [inline]
 ____sys_sendmsg+0x39a/0x510 net/socket.c:2413
 ___sys_sendmsg net/socket.c:2467 [inline]
 __sys_sendmmsg+0x267/0x4c0 net/socket.c:2553
 __do_sys_sendmmsg net/socket.c:2582 [inline]
 __se_sys_sendmmsg net/socket.c:2579 [inline]
 __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2579
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x000000000001677c -> 0x000000000001677d

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 31140 Comm: syz-executor.1 Not tainted 5.17.0-rc7-syzkaller-00227-g68453767131a-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (3):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci2-upstream-kcsan-gce 2022/03/12 19:00 upstream 68453767131a 9e8eaa75 .config console log report info KCSAN: data-race in ip6_tnl_xmit / ip6_tnl_xmit
ci2-upstream-kcsan-gce 2022/02/18 01:03 upstream a3580ac9b7a3 3cd800e4 .config console log report info KCSAN: data-race in ip6_tnl_xmit / ip6_tnl_xmit
ci2-upstream-kcsan-gce 2022/02/02 22:18 upstream 27bb0b18c208 4ebb2798 .config console log report info KCSAN: data-race in ip6_tnl_xmit / ip6_tnl_xmit
* Struck through repros no longer work on HEAD.