syzbot


KCSAN: data-race in unix_dgram_connect / unix_dgram_poll (6)

Status: auto-closed as invalid on 2021/12/03 15:30
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 394d, last: 394d
similar bugs (5):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in unix_dgram_connect / unix_dgram_poll 5 857d 887d 0/24 auto-closed as invalid on 2020/08/27 17:47
upstream KCSAN: data-race in unix_dgram_connect / unix_dgram_poll (3) 4 634d 678d 0/24 auto-closed as invalid on 2021/04/07 19:26
upstream KCSAN: data-race in unix_dgram_connect / unix_dgram_poll (5) 1 471d 471d 0/24 auto-closed as invalid on 2021/09/17 19:26
upstream KCSAN: data-race in unix_dgram_connect / unix_dgram_poll (2) 3 739d 717d 0/24 auto-closed as invalid on 2020/12/25 10:44
upstream KCSAN: data-race in unix_dgram_connect / unix_dgram_poll (4) 2 554d 569d 0/24 auto-closed as invalid on 2021/06/27 09:27

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

write to 0xffff8881303c1230 of 4 bytes by task 11049 on cpu 0:
 unix_dgram_disconnected net/unix/af_unix.c:494 [inline]
 unix_dgram_connect+0x76d/0x8d0 net/unix/af_unix.c:1282
 __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 0xffff8881303c1230 of 4 bytes by task 11037 on cpu 1:
 unix_dgram_poll+0x6e/0x410 net/unix/af_unix.c:3084
 sock_poll+0x23e/0x260 net/socket.c:1302
 vfs_poll include/linux/poll.h:90 [inline]
 ep_item_poll fs/eventpoll.c:846 [inline]
 ep_send_events fs/eventpoll.c:1685 [inline]
 ep_poll fs/eventpoll.c:1799 [inline]
 do_epoll_wait+0x6b7/0xf10 fs/eventpoll.c:2227
 __do_sys_epoll_wait fs/eventpoll.c:2239 [inline]
 __se_sys_epoll_wait fs/eventpoll.c:2234 [inline]
 __x64_sys_epoll_wait+0x119/0x140 fs/eventpoll.c:2234
 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: 0x00000000 -> 0x00000068

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 11037 Comm: syz-executor.5 Not tainted 5.15.0-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 2021/10/29 15:22 upstream f25a5481af12 2353a3ec .config log report info KCSAN: data-race in unix_dgram_connect / unix_dgram_poll
* Struck through repros no longer work on HEAD.