syzbot


KCSAN: data-race in __dentry_kill / d_alloc_parallel

Status: auto-closed as invalid on 2020/04/13 06:40
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 1020d, last: 918d
similar bugs (3):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __dentry_kill / d_alloc_parallel (2) 3 738d 769d 0/23 auto-closed as invalid on 2020/09/05 03:58
upstream KCSAN: data-race in __dentry_kill / d_alloc_parallel (3) 1 701d 701d 0/23 auto-closed as invalid on 2020/10/11 15:50
upstream KCSAN: data-race in __dentry_kill / d_alloc_parallel (4) 1 461d 461d 0/23 auto-closed as invalid on 2021/06/09 01:27

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __dentry_kill / d_alloc_parallel

read to 0xffff8880769c7000 of 4 bytes by task 9355 on cpu 0:
 dentry_unlist fs/dcache.c:544 [inline]
 __dentry_kill+0x1be/0x3c0 fs/dcache.c:575
 dentry_kill fs/dcache.c:698 [inline]
 dput+0x3b5/0x750 fs/dcache.c:859
 path_put_conditional fs/namei.c:821 [inline]
 follow_managed+0x1eb/0x6f0 fs/namei.c:1279
 walk_component+0x4ec/0xd90 fs/namei.c:1808
 link_path_walk.part.0+0x5d3/0xa90 fs/namei.c:2128
 link_path_walk fs/namei.c:2256 [inline]
 path_lookupat.isra.0+0x77/0x5a0 fs/namei.c:2304
 filename_lookup+0x145/0x2b0 fs/namei.c:2335
 user_path_at_empty+0x4c/0x70 fs/namei.c:2615
 user_path_at include/linux/namei.h:49 [inline]
 vfs_statx+0xd9/0x190 fs/stat.c:187
 vfs_stat include/linux/fs.h:3249 [inline]
 __do_sys_newstat+0x51/0xb0 fs/stat.c:341
 __se_sys_newstat fs/stat.c:337 [inline]
 __x64_sys_newstat+0x3a/0x50 fs/stat.c:337
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8880769c7000 of 4 bytes by task 17845 on cpu 1:
 d_alloc_parallel+0x533/0xe00 fs/dcache.c:2612
 __lookup_slow+0xb4/0x2a0 fs/namei.c:1648
 lookup_slow+0x4f/0x70 fs/namei.c:1682
 walk_component+0x490/0xd90 fs/namei.c:1802
 link_path_walk.part.0+0x5d3/0xa90 fs/namei.c:2128
 link_path_walk fs/namei.c:2256 [inline]
 path_lookupat.isra.0+0x77/0x5a0 fs/namei.c:2304
 filename_lookup+0x145/0x2b0 fs/namei.c:2335
 user_path_at_empty+0x4c/0x70 fs/namei.c:2615
 user_path_at include/linux/namei.h:49 [inline]
 vfs_statx+0xd9/0x190 fs/stat.c:187
 vfs_stat include/linux/fs.h:3249 [inline]
 __do_sys_newstat+0x51/0xb0 fs/stat.c:341
 __se_sys_newstat fs/stat.c:337 [inline]
 __x64_sys_newstat+0x3a/0x50 fs/stat.c:337
 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: 17845 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 (36):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2020/02/03 06:35 https://github.com/google/ktsan.git kcsan 245a43005292 93e5e335 .config log report
ci2-upstream-kcsan-gce 2020/01/27 16:28 https://github.com/google/ktsan.git kcsan 245a43005292 56cd6c9b .config log report
ci2-upstream-kcsan-gce 2020/01/27 12:35 https://github.com/google/ktsan.git kcsan 245a43005292 dd56146d .config log report
ci2-upstream-kcsan-gce 2020/01/26 09:51 https://github.com/google/ktsan.git kcsan 245a43005292 f4e7270e .config log report
ci2-upstream-kcsan-gce 2020/01/21 17:04 https://github.com/google/ktsan.git kcsan 245a43005292 8eda0b95 .config log report
ci2-upstream-kcsan-gce 2020/01/18 23:19 https://github.com/google/ktsan.git kcsan 245a43005292 bc8bc756 .config log report
ci2-upstream-kcsan-gce 2020/01/17 15:44 https://github.com/google/ktsan.git kcsan 245a43005292 3de7aabb .config log report
ci2-upstream-kcsan-gce 2020/01/16 04:15 https://github.com/google/ktsan.git kcsan 245a43005292 f9b69507 .config log report
ci2-upstream-kcsan-gce 2020/01/11 03:47 https://github.com/google/ktsan.git kcsan 245a43005292 4c04afaa .config log report
ci2-upstream-kcsan-gce 2020/01/08 09:39 https://github.com/google/ktsan.git kcsan 245a43005292 ddc3e859 .config log report
ci2-upstream-kcsan-gce 2020/01/06 20:30 https://github.com/google/ktsan.git kcsan 245a43005292 53430d97 .config log report
ci2-upstream-kcsan-gce 2019/12/31 20:33 https://github.com/google/ktsan.git kcsan 245a43005292 25a0186e .config log report
ci2-upstream-kcsan-gce 2019/12/23 11:12 https://github.com/google/ktsan.git kcsan 245a43005292 be5c2c81 .config log report
ci2-upstream-kcsan-gce 2019/12/19 23:15 https://github.com/google/ktsan.git kcsan 245a43005292 36650b4b .config log report
ci2-upstream-kcsan-gce 2019/12/18 09:29 https://github.com/google/ktsan.git kcsan 245a43005292 64ca0a37 .config log report
ci2-upstream-kcsan-gce 2019/12/17 04:10 https://github.com/google/ktsan.git kcsan 245a43005292 d13d7958 .config log report
ci2-upstream-kcsan-gce 2019/12/14 11:29 https://github.com/google/ktsan.git kcsan 245a43005292 eef6e580 .config log report
ci2-upstream-kcsan-gce 2019/12/12 21:19 https://github.com/google/ktsan.git kcsan ef798c30ba4e 08003f64 .config log report
ci2-upstream-kcsan-gce 2019/12/10 18:07 https://github.com/google/ktsan.git kcsan ef798c30ba4e 4b83c8fb .config log report
ci2-upstream-kcsan-gce 2019/12/09 20:57 https://github.com/google/ktsan.git kcsan ef798c30ba4e b31eda3d .config log report
ci2-upstream-kcsan-gce 2019/12/07 19:44 https://github.com/google/ktsan.git kcsan ef798c30ba4e 1508f453 .config log report
ci2-upstream-kcsan-gce 2019/12/06 02:50 https://github.com/google/ktsan.git kcsan ef798c30ba4e 98b4ef2d .config log report
ci2-upstream-kcsan-gce 2019/12/03 12:17 https://github.com/google/ktsan.git kcsan ef798c30ba4e ab342da3 .config log report
ci2-upstream-kcsan-gce 2019/11/30 16:56 https://github.com/google/ktsan.git kcsan ef798c30ba4e 3a75be00 .config log report
ci2-upstream-kcsan-gce 2019/11/29 03:34 https://github.com/google/ktsan.git kcsan ef798c30ba4e 76357d6f .config log report
ci2-upstream-kcsan-gce 2019/11/27 02:14 https://github.com/google/ktsan.git kcsan ef798c30ba4e 1048481f .config log report
ci2-upstream-kcsan-gce 2019/11/24 23:12 https://github.com/google/ktsan.git kcsan 5863cc791e4c 598ca6c8 .config log report
ci2-upstream-kcsan-gce 2019/11/18 04:59 https://github.com/google/ktsan.git kcsan 5863cc791e4c d5696d51 .config log report
ci2-upstream-kcsan-gce 2019/11/09 01:50 https://github.com/google/ktsan.git kcsan 94c006602e13 1e35461e .config log report
ci2-upstream-kcsan-gce 2019/11/07 05:25 https://github.com/google/ktsan.git kcsan 94c006602e13 d797d201 .config log report
ci2-upstream-kcsan-gce 2019/11/04 23:26 https://github.com/google/ktsan.git kcsan 94c006602e13 18e12644 .config log report
ci2-upstream-kcsan-gce 2019/11/02 02:21 https://github.com/google/ktsan.git kcsan 05f2236801fe 997ccc67 .config log report
ci2-upstream-kcsan-gce 2019/10/31 13:46 https://github.com/google/ktsan.git kcsan 05f2236801fe a41ca8fa .config log report
ci2-upstream-kcsan-gce 2019/10/26 00:21 https://github.com/google/ktsan.git kcsan 05f2236801fe 413926c5 .config log report
ci2-upstream-kcsan-gce 2019/10/24 18:36 https://github.com/google/ktsan.git kcsan 05f2236801fe d01bb02a .config log report
ci2-upstream-kcsan-gce 2019/10/23 18:15 https://github.com/google/ktsan.git kcsan 05f2236801fe b602d64b .config log report