syzbot


KCSAN: data-race in udpv6_sendmsg / udpv6_sendmsg (4)

Status: auto-closed as invalid on 2021/09/03 03:58
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 532d, last: 532d
similar bugs (3):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in udpv6_sendmsg / udpv6_sendmsg 1 874d 874d 0/24 auto-closed as invalid on 2020/08/23 02:37
upstream KCSAN: data-race in udpv6_sendmsg / udpv6_sendmsg (3) 1 588d 588d 0/24 auto-closed as invalid on 2021/06/05 06:06
upstream KCSAN: data-race in udpv6_sendmsg / udpv6_sendmsg (2) 1 826d 826d 0/24 auto-closed as invalid on 2020/10/10 02:50

Sample crash report:
==================================================================
BUG: KCSAN: data-race in udpv6_sendmsg / udpv6_sendmsg

write to 0xffff888136d5fdf0 of 4 bytes by task 7819 on cpu 0:
 udpv6_sendmsg+0x15bc/0x16b0 net/ipv6/udp.c:1548
 inet6_sendmsg+0x5f/0x80 net/ipv6/af_inet6.c:642
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg net/socket.c:674 [inline]
 ____sys_sendmsg+0x360/0x4d0 net/socket.c:2337
 ___sys_sendmsg net/socket.c:2391 [inline]
 __sys_sendmmsg+0x315/0x4b0 net/socket.c:2477
 __do_sys_sendmmsg net/socket.c:2506 [inline]
 __se_sys_sendmmsg net/socket.c:2503 [inline]
 __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2503
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888136d5fdf0 of 4 bytes by task 7821 on cpu 1:
 udpv6_sendmsg+0x201/0x16b0 net/ipv6/udp.c:1328
 inet6_sendmsg+0x5f/0x80 net/ipv6/af_inet6.c:642
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg net/socket.c:674 [inline]
 ____sys_sendmsg+0x360/0x4d0 net/socket.c:2337
 ___sys_sendmsg net/socket.c:2391 [inline]
 __sys_sendmmsg+0x315/0x4b0 net/socket.c:2477
 __do_sys_sendmmsg net/socket.c:2506 [inline]
 __se_sys_sendmmsg net/socket.c:2503 [inline]
 __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2503
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000000 -> 0x0000000a

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7821 Comm: syz-executor.5 Not tainted 5.13.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2021/06/25 20:05 upstream 44db63d1ad8d ae6bf8dd .config log report info KCSAN: data-race in udpv6_sendmsg / udpv6_sendmsg
* Struck through repros no longer work on HEAD.