syzbot


KCSAN: data-race in unix_gc / wait_for_unix_gc (3)

Status: auto-closed as invalid on 2021/09/27 04:17
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 471d, last: 471d
similar bugs (3):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in unix_gc / wait_for_unix_gc (2) 5 528d 563d 0/24 auto-closed as invalid on 2021/08/01 20:33
upstream KCSAN: data-race in unix_gc / wait_for_unix_gc 1 708d 708d 0/24 auto-closed as invalid on 2021/02/02 07:05
upstream KCSAN: data-race in unix_gc / wait_for_unix_gc (4) 2 400d 419d 0/24 auto-closed as invalid on 2021/12/07 18:51

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

write to 0xffffffff841bad93 of 1 bytes by task 19611 on cpu 0:
 unix_gc+0x839/0x8d0 net/unix/garbage.c:302
 unix_release_sock+0x644/0x6f0 net/unix/af_unix.c:598
 unix_release+0x2f/0x50 net/unix/af_unix.c:867
 __sock_release net/socket.c:648 [inline]
 sock_release+0x40/0xd0 net/socket.c:676
 io_ring_ctx_free fs/io_uring.c:8702 [inline]
 io_ring_exit_work+0xe4f/0x1390 fs/io_uring.c:8861
 process_one_work+0x3e9/0x8f0 kernel/workqueue.c:2276
 worker_thread+0x636/0xae0 kernel/workqueue.c:2422
 kthread+0x262/0x280 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

read to 0xffffffff841bad93 of 1 bytes by task 21303 on cpu 1:
 wait_for_unix_gc+0xb2/0x140 net/unix/garbage.c:198
 unix_dgram_sendmsg+0x5f/0x1600 net/unix/af_unix.c:1684
 sock_sendmsg_nosec net/socket.c:703 [inline]
 sock_sendmsg+0x75/0xa0 net/socket.c:723
 io_send fs/io_uring.c:4451 [inline]
 io_issue_sqe+0x1f4f/0x64b0 fs/io_uring.c:6205
 __io_queue_sqe+0xe7/0x360 fs/io_uring.c:6470
 io_queue_sqe fs/io_uring.c:6513 [inline]
 io_submit_sqe+0x1695/0x3400 fs/io_uring.c:6668
 io_submit_sqes+0x822/0xe50 fs/io_uring.c:6784
 __do_sys_io_uring_enter fs/io_uring.c:9392 [inline]
 __se_sys_io_uring_enter+0x213/0xae0 fs/io_uring.c:9334
 __x64_sys_io_uring_enter+0x74/0x80 fs/io_uring.c:9334
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x01 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 21303 Comm: syz-executor.4 Not tainted 5.14.0-rc6-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 2021/08/23 04:16 upstream 1bdc3d5be7e1 b599f2fc .config log report info KCSAN: data-race in unix_gc / wait_for_unix_gc
* Struck through repros no longer work on HEAD.