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KCSAN: data-race in fasync_remove_entry / kill_fasync (9)

Status: auto-obsoleted due to no activity on 2023/01/02 11:50
Subsystems: fs
[Documentation on labels]
First crash: 523d, last: 523d
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 1342d 1342d 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 303d 303d 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 1073d 1073d 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 1003d 1005d 0/26 auto-closed as invalid on 2021/08/31 22:21
upstream KCSAN: data-race in fasync_remove_entry / kill_fasync (3) fs 1 1225d 1225d 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 943d 943d 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 864d 902d 0/26 auto-closed as invalid on 2022/01/18 10:05
upstream KCSAN: data-race in fasync_remove_entry / kill_fasync (8) fs 3 809d 818d 0/26 auto-closed as invalid on 2022/03/14 14:59
upstream KCSAN: data-race in fasync_remove_entry / kill_fasync fs 82 1396d 1553d 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 0xffff88813da9ee08 of 8 bytes by task 3267 on cpu 1:
 fasync_remove_entry+0xd5/0x130 fs/fcntl.c:877
 fasync_helper+0x92/0xc0 fs/fcntl.c:976
 pipe_fasync+0x8f/0x160 fs/pipe.c:746
 __fput+0x532/0x570 fs/file_table.c:317
 ____fput+0x11/0x20 fs/file_table.c:348
 task_work_run+0xde/0x110 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0x124/0x130 kernel/entry/common.c:171
 exit_to_user_mode_prepare kernel/entry/common.c:203 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x6a/0x90 kernel/entry/common.c:296
 do_syscall_64+0x37/0x70 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88813da9ee08 of 8 bytes by task 3264 on cpu 0:
 kill_fasync+0x20/0x160 fs/fcntl.c:1015
 wakeup_pipe_readers fs/splice.c:168 [inline]
 splice_file_to_pipe+0x2e5/0x360 fs/splice.c:1016
 do_splice+0xc05/0xd90 fs/splice.c:1099
 __do_splice fs/splice.c:1139 [inline]
 __do_sys_splice fs/splice.c:1346 [inline]
 __se_sys_splice+0x2a4/0x380 fs/splice.c:1328
 __x64_sys_splice+0x74/0x80 fs/splice.c:1328
 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+0x63/0xcd

value changed: 0xffff88813ab120c0 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3264 Comm: syz-executor.1 Not tainted 6.1.0-rc5-syzkaller-00326-g77c51ba552a1-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/11/20 19:44 upstream 77c51ba552a1 5bb70014 .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.