syzbot


KCSAN: data-race in __ip4_datagram_connect / udpv6_sendmsg (2)

Status: auto-closed as invalid on 2021/10/15 20:11
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 453d, last: 453d
similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __ip4_datagram_connect / udpv6_sendmsg 2 910d 968d 0/24 closed as invalid on 2020/06/18 14:24

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __ip4_datagram_connect / udpv6_sendmsg

write to 0xffff888131c0304c of 2 bytes by task 20902 on cpu 0:
 __ip4_datagram_connect+0x61b/0x710 net/ipv4/datagram.c:72
 __ip6_datagram_connect+0x576/0x860 net/ipv6/datagram.c:189
 ip6_datagram_connect+0x2a/0x40 net/ipv6/datagram.c:272
 inet_dgram_connect+0x107/0x190 net/ipv4/af_inet.c:580
 __sys_connect_file net/socket.c:1896 [inline]
 __sys_connect+0x254/0x290 net/socket.c:1913
 __do_sys_connect net/socket.c:1923 [inline]
 __se_sys_connect net/socket.c:1920 [inline]
 __x64_sys_connect+0x3d/0x50 net/socket.c:1920
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888131c0304c of 2 bytes by task 20964 on cpu 1:
 udpv6_sendmsg+0x851/0x16e0 net/ipv6/udp.c:1425
 inet6_sendmsg+0x5f/0x80 net/ipv6/af_inet6.c:643
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg net/socket.c:724 [inline]
 __sys_sendto+0x302/0x3e0 net/socket.c:2036
 __do_sys_sendto net/socket.c:2048 [inline]
 __se_sys_sendto net/socket.c:2044 [inline]
 __x64_sys_sendto+0x74/0x90 net/socket.c:2044
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000 -> 0x214e

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 20964 Comm: syz-executor.0 Not tainted 5.14.0-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 2021/09/10 20:06 upstream bf9f243f23e6 5ae8508a .config log report info KCSAN: data-race in __ip4_datagram_connect / udpv6_sendmsg
* Struck through repros no longer work on HEAD.