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KCSAN: data-race in sk_stream_wait_connect / tcp_disconnect (2)

Status: fixed on 2023/07/01 16:05
Subsystems: net
[Documentation on labels]
Fix commit: d0ac89f6f987 net: deal with most data-races in sk_wait_event()
First crash: 474d, last: 474d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in sk_stream_wait_connect / tcp_disconnect net 2 1320d 1323d 0/27 auto-closed as invalid on 2021/01/17 13:57

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

write to 0xffff88812d83d6a0 of 4 bytes by task 9065 on cpu 1:
 tcp_disconnect+0x2cd/0xdb0
 inet_shutdown+0x19e/0x1f0 net/ipv4/af_inet.c:911
 __sys_shutdown_sock net/socket.c:2343 [inline]
 __sys_shutdown net/socket.c:2355 [inline]
 __do_sys_shutdown net/socket.c:2363 [inline]
 __se_sys_shutdown+0xf8/0x140 net/socket.c:2361
 __x64_sys_shutdown+0x31/0x40 net/socket.c:2361
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88812d83d6a0 of 4 bytes by task 9040 on cpu 0:
 sk_stream_wait_connect+0x1de/0x3a0 net/core/stream.c:75
 tcp_sendmsg_locked+0x2e4/0x2120 net/ipv4/tcp.c:1266
 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1484
 inet6_sendmsg+0x63/0x80 net/ipv6/af_inet6.c:651
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg net/socket.c:747 [inline]
 __sys_sendto+0x246/0x300 net/socket.c:2142
 __do_sys_sendto net/socket.c:2154 [inline]
 __se_sys_sendto net/socket.c:2150 [inline]
 __x64_sys_sendto+0x78/0x90 net/socket.c:2150
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00000000 -> 0x00000068

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 9040 Comm: syz-executor.3 Not tainted 6.3.0-rc5-syzkaller-00153-gaa318c48808c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/04/07 22:34 upstream aa318c48808c 71147e29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in sk_stream_wait_connect / tcp_disconnect
* Struck through repros no longer work on HEAD.