syzbot


KCSAN: data-race in netlink_connect / netlink_sendmsg

Status: auto-closed as invalid on 2022/05/29 12:20
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 218d, last: 218d

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

write to 0xffff8880237b8b0c of 4 bytes by task 18959 on cpu 1:
 netlink_connect+0x1fe/0x270 net/netlink/af_netlink.c:1112
 __sys_connect_file net/socket.c:1900 [inline]
 __sys_connect+0x197/0x1b0 net/socket.c:1917
 __do_sys_connect net/socket.c:1927 [inline]
 __se_sys_connect net/socket.c:1924 [inline]
 __x64_sys_connect+0x3d/0x50 net/socket.c:1924
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8880237b8b0c of 4 bytes by task 18958 on cpu 0:
 netlink_sendmsg+0x299/0x750 net/netlink/af_netlink.c:1878
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg net/socket.c:725 [inline]
 sock_write_iter+0x1a3/0x200 net/socket.c:1061
 call_write_iter include/linux/fs.h:2050 [inline]
 new_sync_write fs/read_write.c:504 [inline]
 vfs_write+0x71c/0x890 fs/read_write.c:591
 ksys_write+0xe8/0x1a0 fs/read_write.c:644
 __do_sys_write fs/read_write.c:656 [inline]
 __se_sys_write fs/read_write.c:653 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:653
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 18958 Comm: syz-executor.2 Not tainted 5.18.0-rc3-syzkaller-00235-g22da5264abf4-dirty #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 2022/04/24 12:17 upstream 22da5264abf4 131df97d .config log report info KCSAN: data-race in netlink_connect / netlink_sendmsg
* Struck through repros no longer work on HEAD.