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KCSAN: data-race in fasync_remove_entry / kill_fasync (8)

Status: auto-closed as invalid on 2022/03/14 14:59
Subsystems: fs
[Documentation on labels]
First crash: 789d, last: 780d
Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in fasync_remove_entry / kill_fasync (2) fs 1 1313d 1313d 0/26 auto-closed as invalid on 2020/09/27 12:17
upstream KCSAN: data-race in fasync_remove_entry / kill_fasync (10) fs 1 274d 274d 0/26 auto-obsoleted due to no activity on 2023/08/01 22:11
upstream KCSAN: data-race in fasync_remove_entry / kill_fasync (4) fs 1 1044d 1044d 0/26 auto-closed as invalid on 2021/06/23 11:06
upstream KCSAN: data-race in fasync_remove_entry / kill_fasync (5) fs 2 974d 976d 0/26 auto-closed as invalid on 2021/08/31 22:21
upstream KCSAN: data-race in fasync_remove_entry / kill_fasync (9) fs 1 493d 493d 0/26 auto-obsoleted due to no activity on 2023/01/02 11:50
upstream KCSAN: data-race in fasync_remove_entry / kill_fasync (3) fs 1 1196d 1196d 0/26 auto-closed as invalid on 2021/01/22 14:57
upstream KCSAN: data-race in fasync_remove_entry / kill_fasync (6) fs 1 913d 913d 0/26 auto-closed as invalid on 2021/10/31 16:09
upstream KCSAN: data-race in fasync_remove_entry / kill_fasync (7) fs 4 835d 873d 0/26 auto-closed as invalid on 2022/01/18 10:05
upstream KCSAN: data-race in fasync_remove_entry / kill_fasync fs 82 1367d 1524d 0/26 auto-closed as invalid on 2020/08/04 12:11

Sample crash report:
==================================================================
BUG: KCSAN: data-race in fasync_remove_entry / kill_fasync

write to 0xffff888135ce8058 of 8 bytes by task 20477 on cpu 1:
 fasync_remove_entry+0xd5/0x140 fs/fcntl.c:895
 fasync_helper+0x92/0xc0 fs/fcntl.c:994
 sock_fasync+0x5c/0xc0 net/socket.c:1343
 __fput+0x4dd/0x520 fs/file_table.c:308
 ____fput+0x11/0x20 fs/file_table.c:344
 task_work_run+0x8e/0x110 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x160/0x190 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:300
 do_syscall_64+0x50/0xd0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888135ce8058 of 8 bytes by task 20475 on cpu 0:
 kill_fasync+0x20/0x160 fs/fcntl.c:1033
 sock_wake_async+0xea/0x100
 sk_wake_async include/net/sock.h:2444 [inline]
 unix_release_sock+0x38d/0x6a0 net/unix/af_unix.c:612
 unix_release+0x4e/0x70 net/unix/af_unix.c:990
 __sock_release net/socket.c:650 [inline]
 sock_close+0x6c/0x150 net/socket.c:1318
 __fput+0x295/0x520 fs/file_table.c:311
 ____fput+0x11/0x20 fs/file_table.c:344
 task_work_run+0x8e/0x110 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x160/0x190 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:300
 do_syscall_64+0x50/0xd0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0xffff8881369c11b0 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 20475 Comm: syz-executor.5 Not tainted 5.17.0-rc3-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/02/07 14:52 upstream dfd42facf1e4 a7dab638 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in fasync_remove_entry / kill_fasync
2022/02/06 18:14 upstream 90c9e950c0de a7dab638 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in fasync_remove_entry / kill_fasync
2022/01/29 12:50 upstream 169387e2aa29 495e00c5 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in fasync_remove_entry / kill_fasync
* Struck through repros no longer work on HEAD.