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KCSAN: data-race in generic_permission / kernfs_refresh_inode

Status: closed as invalid on 2019/10/15 15:50
Subsystems: kernfs
[Documentation on labels]
First crash: 1658d, last: 1647d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in generic_permission / kernfs_refresh_inode (2) kernfs 35 1620d 1647d 0/26 closed as invalid on 2019/11/19 14:04
upstream KCSAN: data-race in generic_permission / kernfs_refresh_inode (3) kernfs 3 1538d 1578d 0/26 auto-closed as invalid on 2020/04/11 12:29

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

write to 0xffff88812a7e76d8 of 2 bytes by task 3990 on cpu 1:
 kernfs_refresh_inode+0x44/0x180 fs/kernfs/inode.c:173
 kernfs_iop_permission+0x66/0xa0 fs/kernfs/inode.c:284
 do_inode_permission fs/namei.c:384 [inline]
 inode_permission+0x241/0x3c0 fs/namei.c:449
 may_lookup fs/namei.c:1700 [inline]
 link_path_walk.part.0+0x622/0xa90 fs/namei.c:2082
 link_path_walk fs/namei.c:2267 [inline]
 path_lookupat.isra.0+0x77/0x5a0 fs/namei.c:2315
 filename_lookup+0x145/0x2d0 fs/namei.c:2346
 user_path_at_empty+0x4c/0x70 fs/namei.c:2606
 user_path_at include/linux/namei.h:60 [inline]
 vfs_statx+0xd9/0x190 fs/stat.c:187
 vfs_lstat include/linux/fs.h:3193 [inline]
 __do_sys_newlstat+0x51/0xb0 fs/stat.c:354
 __se_sys_newlstat fs/stat.c:348 [inline]
 __x64_sys_newlstat+0x3a/0x50 fs/stat.c:348
 do_syscall_64+0xcf/0x2f0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88812a7e76d8 of 2 bytes by task 3991 on cpu 0:
 acl_permission_check fs/namei.c:295 [inline]
 generic_permission+0x36/0x3d0 fs/namei.c:339
 kernfs_iop_permission+0x7d/0xa0 fs/kernfs/inode.c:287
 do_inode_permission fs/namei.c:384 [inline]
 inode_permission+0x241/0x3c0 fs/namei.c:449
 may_lookup fs/namei.c:1700 [inline]
 link_path_walk.part.0+0x622/0xa90 fs/namei.c:2082
 link_path_walk fs/namei.c:2070 [inline]
 path_openat+0x14f/0x3530 fs/namei.c:3532
 do_filp_open+0x11e/0x1b0 fs/namei.c:3563
 do_sys_open+0x3b3/0x4f0 fs/open.c:1089
 __do_sys_open fs/open.c:1107 [inline]
 __se_sys_open fs/open.c:1102 [inline]
 __x64_sys_open+0x55/0x70 fs/open.c:1102
 do_syscall_64+0xcf/0x2f0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3991 Comm: udevd Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (20):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/10/15 10:48 https://github.com/google/ktsan.git kcsan 81f95ec7998e b5268b89 .config console log report ci2-upstream-kcsan-gce
2019/10/15 10:06 https://github.com/google/ktsan.git kcsan 81f95ec7998e 05ad7292 .config console log report ci2-upstream-kcsan-gce
2019/10/15 09:41 https://github.com/google/ktsan.git kcsan 81f95ec7998e 05ad7292 .config console log report ci2-upstream-kcsan-gce
2019/10/15 06:01 https://github.com/google/ktsan.git kcsan d724f94f63de 05ad7292 .config console log report ci2-upstream-kcsan-gce
2019/10/14 22:42 https://github.com/google/ktsan.git kcsan d724f94f63de 05ad7292 .config console log report ci2-upstream-kcsan-gce
2019/10/14 22:26 https://github.com/google/ktsan.git kcsan d724f94f63de 05ad7292 .config console log report ci2-upstream-kcsan-gce
2019/10/14 09:32 https://github.com/google/ktsan.git kcsan d724f94f63de a6aef847 .config console log report ci2-upstream-kcsan-gce
2019/10/11 19:03 https://github.com/google/ktsan.git kcsan d724f94f63de 426631dd .config console log report ci2-upstream-kcsan-gce
2019/10/08 21:13 https://github.com/google/ktsan.git kcsan d724f94f63de b1ebbfef .config console log report ci2-upstream-kcsan-gce
2019/10/08 18:00 https://github.com/google/ktsan.git kcsan d724f94f63de b1ebbfef .config console log report ci2-upstream-kcsan-gce
2019/10/08 13:49 https://github.com/google/ktsan.git kcsan 3675607974a2 137e37ca .config console log report ci2-upstream-kcsan-gce
2019/10/08 13:30 https://github.com/google/ktsan.git kcsan 3675607974a2 137e37ca .config console log report ci2-upstream-kcsan-gce
2019/10/08 11:59 https://github.com/google/ktsan.git kcsan c1c7521f03c7 64612bfd .config console log report ci2-upstream-kcsan-gce
2019/10/08 11:33 https://github.com/google/ktsan.git kcsan c1c7521f03c7 64612bfd .config console log report ci2-upstream-kcsan-gce
2019/10/08 10:59 https://github.com/google/ktsan.git kcsan c1c7521f03c7 64612bfd .config console log report ci2-upstream-kcsan-gce
2019/10/08 10:50 https://github.com/google/ktsan.git kcsan c1c7521f03c7 64612bfd .config console log report ci2-upstream-kcsan-gce
2019/10/07 08:27 https://github.com/google/ktsan.git kcsan c1c7521f03c7 28ac6e64 .config console log report ci2-upstream-kcsan-gce
2019/10/05 04:27 https://github.com/google/ktsan.git kcsan c1c7521f03c7 f3f7d9c8 .config console log report ci2-upstream-kcsan-gce
2019/10/04 15:47 https://github.com/google/ktsan.git kcsan b4bd934316dc c86336cf .config console log report ci2-upstream-kcsan-gce
2019/10/04 14:36 https://github.com/google/ktsan.git kcsan b4bd934316dc c86336cf .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.