KCSAN: data-race in do_dentry_open / kernfs_refresh_inode

Status: auto-closed as invalid on 2020/04/15 15:53
Subsystems: kernfs
[Documentation on labels]
First crash: 2478d, last: 2381d

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

read to 0xffff8881251f5bf8 of 2 bytes by task 5345 on cpu 1:
 do_dentry_open+0xf0/0x970 fs/open.c:757
 vfs_open+0x62/0x80 fs/open.c:914
 do_last fs/namei.c:3420 [inline]
 path_openat+0xf9f/0x3580 fs/namei.c:3537
 do_filp_open+0x11e/0x1b0 fs/namei.c:3567
 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/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8881251f5bf8 of 2 bytes by task 3988 on cpu 0:
 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+0x241/0x370 fs/namei.c:449
 may_open.isra.0+0x144/0x250 fs/namei.c:2980
 do_last fs/namei.c:3416 [inline]
 path_openat+0xf31/0x3580 fs/namei.c:3537
 do_filp_open+0x11e/0x1b0 fs/namei.c:3567
 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/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3988 Comm: udevd Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (11):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/02/05 15:44 https://github.com/google/ktsan.git kcsan 245a43005292 662cf49a .config console log report ci2-upstream-kcsan-gce
2020/02/02 04:40 https://github.com/google/ktsan.git kcsan 245a43005292 2274ad39 .config console log report ci2-upstream-kcsan-gce
2020/01/27 16:04 https://github.com/google/ktsan.git kcsan 245a43005292 56cd6c9b .config console log report ci2-upstream-kcsan-gce
2020/01/13 18:37 https://github.com/google/ktsan.git kcsan 245a43005292 99565c1a .config console log report ci2-upstream-kcsan-gce
2020/01/08 04:37 https://github.com/google/ktsan.git kcsan 245a43005292 6738e0b3 .config console log report ci2-upstream-kcsan-gce
2020/01/07 12:54 https://github.com/google/ktsan.git kcsan 245a43005292 1bcd407e .config console log report ci2-upstream-kcsan-gce
2019/11/18 12:02 https://github.com/google/ktsan.git kcsan 5863cc791e4c d5696d51 .config console log report ci2-upstream-kcsan-gce
2019/11/08 07:17 https://github.com/google/ktsan.git kcsan 94c006602e13 1e35461e .config console log report ci2-upstream-kcsan-gce
2019/11/04 19:40 https://github.com/google/ktsan.git kcsan 94c006602e13 18e12644 .config console log report ci2-upstream-kcsan-gce
2019/11/04 02:57 https://github.com/google/ktsan.git kcsan 05f2236801fe b35fad31 .config console log report ci2-upstream-kcsan-gce
2019/10/31 01:35 https://github.com/google/ktsan.git kcsan 05f2236801fe a41ca8fa .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.