KCSAN: data-race in pid_update_inode / security_file_open

Status: auto-closed as invalid on 2020/04/10 21:18
Subsystems: lsm
[Documentation on labels]
First crash: 2474d, last: 2383d

Sample crash report:
==================================================================
BUG: KCSAN: data-race in pid_update_inode / security_file_open

read to 0xffff888125210d68 of 2 bytes by task 12903 on cpu 0:
 fsnotify_perm include/linux/fsnotify.h:82 [inline]
 security_file_open+0x11c/0x210 security/security.c:1501
 do_dentry_open+0x211/0x970 fs/open.c:784
 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 0xffff888125210d68 of 2 bytes by task 12911 on cpu 1:
 pid_update_inode+0x51/0x70 fs/proc/base.c:1820
 pid_revalidate+0x91/0x120 fs/proc/base.c:1841
 d_revalidate fs/namei.c:758 [inline]
 d_revalidate fs/namei.c:755 [inline]
 lookup_fast+0x612/0x6c0 fs/namei.c:1618
 do_last fs/namei.c:3291 [inline]
 path_openat+0x2ac/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: 1 PID: 12911 Comm: ps Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (15):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/01/31 21:16 https://github.com/google/ktsan.git kcsan 245a43005292 0eb59c27 .config console log report ci2-upstream-kcsan-gce
2020/01/16 15:45 https://github.com/google/ktsan.git kcsan 245a43005292 3de7aabb .config console log report ci2-upstream-kcsan-gce
2020/01/10 15:38 https://github.com/google/ktsan.git kcsan 245a43005292 532ec44e .config console log report ci2-upstream-kcsan-gce
2019/12/18 05:53 https://github.com/google/ktsan.git kcsan 245a43005292 64ca0a37 .config console log report ci2-upstream-kcsan-gce
2019/12/17 01:03 https://github.com/google/ktsan.git kcsan 245a43005292 d13d7958 .config console log report ci2-upstream-kcsan-gce
2019/12/12 05:50 https://github.com/google/ktsan.git kcsan ef798c30ba4e d973f528 .config console log report ci2-upstream-kcsan-gce
2019/12/09 13:51 https://github.com/google/ktsan.git kcsan ef798c30ba4e b31eda3d .config console log report ci2-upstream-kcsan-gce
2019/12/07 19:41 https://github.com/google/ktsan.git kcsan ef798c30ba4e 1508f453 .config console log report ci2-upstream-kcsan-gce
2019/12/05 15:06 https://github.com/google/ktsan.git kcsan ef798c30ba4e 9fd5a512 .config console log report ci2-upstream-kcsan-gce
2019/11/22 11:27 https://github.com/google/ktsan.git kcsan 5863cc791e4c 598ca6c8 .config console log report ci2-upstream-kcsan-gce
2019/11/20 22:13 https://github.com/google/ktsan.git kcsan 5863cc791e4c 8098ea0f .config console log report ci2-upstream-kcsan-gce
2019/11/16 05:24 https://github.com/google/ktsan.git kcsan 5863cc791e4c cdac920b .config console log report ci2-upstream-kcsan-gce
2019/11/09 23:07 https://github.com/google/ktsan.git kcsan 94c006602e13 dc438b91 .config console log report ci2-upstream-kcsan-gce
2019/11/07 15:06 https://github.com/google/ktsan.git kcsan 94c006602e13 d5bc6812 .config console log report ci2-upstream-kcsan-gce
2019/11/01 18:26 https://github.com/google/ktsan.git kcsan 05f2236801fe 997ccc67 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.