syzbot


KCSAN: data-race in fsnotify / fsnotify_detach_mark (8)

Status: auto-closed as invalid on 2022/01/29 00:14
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 282d, last: 282d
similar bugs (7):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in fsnotify / fsnotify_detach_mark (5) 2 678d 664d 0/24 auto-closed as invalid on 2020/12/28 12:08
upstream KCSAN: data-race in fsnotify / fsnotify_detach_mark (4) 1 734d 734d 0/24 auto-closed as invalid on 2020/11/02 17:43
upstream KCSAN: data-race in fsnotify / fsnotify_detach_mark 6 891d 1038d 0/24 auto-closed as invalid on 2020/06/18 13:43
upstream KCSAN: data-race in fsnotify / fsnotify_detach_mark (7) 1 362d 362d 0/24 auto-closed as invalid on 2021/11/09 20:25
upstream KCSAN: data-race in fsnotify / fsnotify_detach_mark (6) 1 636d 636d 0/24 auto-closed as invalid on 2021/02/08 06:39
upstream KCSAN: data-race in fsnotify / fsnotify_detach_mark (2) 1 829d 829d 0/24 auto-closed as invalid on 2020/07/31 05:33
upstream KCSAN: data-race in fsnotify / fsnotify_detach_mark (3) 1 778d 778d 0/24 auto-closed as invalid on 2020/09/19 20:21

Sample crash report:
==================================================================
BUG: KCSAN: data-race in fsnotify / fsnotify_detach_mark

write to 0xffff888102ef5774 of 4 bytes by task 6724 on cpu 1:
 fsnotify_detach_mark+0x7e/0x110 fs/notify/mark.c:414
 fsnotify_clear_marks_by_group+0x29b/0x3e0 fs/notify/mark.c:786
 fsnotify_destroy_group+0x51/0x180 fs/notify/group.c:61
 inotify_release+0x21/0x30 fs/notify/inotify/inotify_user.c:286
 __fput+0x295/0x520 fs/file_table.c:280
 ____fput+0x11/0x20 fs/file_table.c:313
 task_work_run+0x8e/0x110 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [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 0xffff888102ef5774 of 4 bytes by task 6725 on cpu 0:
 send_to_group fs/notify/fsnotify.c:338 [inline]
 fsnotify+0x843/0xf00 fs/notify/fsnotify.c:543
 __fsnotify_parent+0x40e/0x490 fs/notify/fsnotify.c:232
 fsnotify_parent include/linux/fsnotify.h:77 [inline]
 fsnotify_file include/linux/fsnotify.h:99 [inline]
 fsnotify_modify include/linux/fsnotify.h:277 [inline]
 do_iter_write+0x4e2/0x5c0 fs/read_write.c:855
 vfs_iter_write+0x4c/0x70 fs/read_write.c:892
 iter_file_splice_write+0x43a/0x790 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0x106/0x190 fs/splice.c:979
 do_sendfile+0x675/0xc40 fs/read_write.c:1245
 __do_sys_sendfile64 fs/read_write.c:1304 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0xb9/0x140 fs/read_write.c:1296
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000006 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 6725 Comm: syz-executor.5 Not tainted 5.16.0-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 2021/12/25 00:11 upstream b927dfc67d05 6caa12e4 .config log report info KCSAN: data-race in fsnotify / fsnotify_detach_mark
* Struck through repros no longer work on HEAD.