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KCSAN: data-race in fsnotify / fsnotify_detach_connector_from_object (4)

Status: auto-obsoleted due to no activity on 2024/06/12 06:08
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+8049759a3f6c9b61f219@syzkaller.appspotmail.com
First crash: 38d, last: 38d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in fsnotify / fsnotify_detach_connector_from_object (2) fs 44 1458d 1628d 0/27 closed as invalid on 2020/06/18 14:24
upstream KCSAN: data-race in fsnotify / fsnotify_detach_connector_from_object fs 2 1679d 1681d 0/27 closed as invalid on 2019/11/19 14:44
upstream KCSAN: data-race in fsnotify / fsnotify_detach_connector_from_object (3) fs 957 69d 190d 0/27 auto-obsoleted due to no activity on 2024/05/05 06:09

Sample crash report:
EXT4-fs (loop4): unmounting filesystem 00000005-0000-0000-0000-000000000000.
==================================================================
BUG: KCSAN: data-race in fsnotify / fsnotify_detach_connector_from_object

write to 0xffff8881001ce904 of 4 bytes by task 4005 on cpu 0:
 fsnotify_detach_connector_from_object+0xcc/0x280 fs/notify/mark.c:253
 fsnotify_put_mark+0x198/0x3c0 fs/notify/mark.c:316
 __do_sys_inotify_rm_watch fs/notify/inotify/inotify_user.c:819 [inline]
 __se_sys_inotify_rm_watch+0x105/0x180 fs/notify/inotify/inotify_user.c:793
 __x64_sys_inotify_rm_watch+0x31/0x40 fs/notify/inotify/inotify_user.c:793
 x64_sys_call+0x2735/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:256
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881001ce904 of 4 bytes by task 3099 on cpu 1:
 fsnotify+0x2b9/0x1160 fs/notify/fsnotify.c:538
 __fsnotify_parent+0x285/0x370 fs/notify/fsnotify.c:236
 fsnotify_parent include/linux/fsnotify.h:83 [inline]
 fsnotify_file include/linux/fsnotify.h:106 [inline]
 fsnotify_close include/linux/fsnotify.h:387 [inline]
 __fput+0x1ff/0x660 fs/file_table.c:408
 __fput_sync+0x44/0x60 fs/file_table.c:507
 __do_sys_close fs/open.c:1556 [inline]
 __se_sys_close+0x101/0x1b0 fs/open.c:1541
 __x64_sys_close+0x1f/0x30 fs/open.c:1541
 x64_sys_call+0x25b9/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:4
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00002008 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3099 Comm: syz-executor.4 Not tainted 6.9.0-rc7-syzkaller-00012-gdccb07f2914c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/08 06:07 upstream dccb07f2914c 4cf3f9b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify / fsnotify_detach_connector_from_object
* Struck through repros no longer work on HEAD.