syzbot


KCSAN: data-race in __fput / kernfs_refresh_inode

Status: closed as invalid on 2019/11/19 13:44
Subsystems: kernfs
[Documentation on labels]
First crash: 1607d, last: 1605d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __fput / kernfs_refresh_inode (2) kernfs 3 1533d 1574d 0/26 auto-closed as invalid on 2020/03/25 20:02

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __fput / kernfs_refresh_inode

write to 0xffff88812589c248 of 2 bytes by task 30143 on cpu 1:
 kernfs_refresh_inode+0x42/0x140 fs/kernfs/inode.c:172
 kernfs_iop_permission+0x66/0xa0 fs/kernfs/inode.c:283
 do_inode_permission fs/namei.c:384 [inline]
 inode_permission+0x241/0x3c0 fs/namei.c:449
 may_open.isra.0+0x144/0x250 fs/namei.c:2963
 do_last fs/namei.c:3404 [inline]
 path_openat+0xf05/0x36e0 fs/namei.c:3525
 do_filp_open+0x11e/0x1b0 fs/namei.c:3555
 do_sys_open+0x3b3/0x4f0 fs/open.c:1097
 __do_sys_open fs/open.c:1115 [inline]
 __se_sys_open fs/open.c:1110 [inline]
 __x64_sys_open+0x55/0x70 fs/open.c:1110
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88812589c248 of 2 bytes by task 3888 on cpu 0:
 fsnotify_close include/linux/fsnotify.h:286 [inline]
 __fput+0xca/0x520 fs/file_table.c:266
 ____fput+0x1f/0x30 fs/file_table.c:313
 task_work_run+0xf6/0x130 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x353/0x370 arch/x86/entry/common.c:300
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3888 Comm: udevd Not tainted 5.4.0-rc6+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/11/05 04:13 https://github.com/google/ktsan.git kcsan 94c006602e13 76630fc9 .config console log report ci2-upstream-kcsan-gce
2019/11/03 11:54 https://github.com/google/ktsan.git kcsan 05f2236801fe c9610487 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.