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KCSAN: data-race in __dentry_kill / step_into (4)

Status: auto-closed as invalid on 2022/04/03 02:19
Subsystems: fs
[Documentation on labels]
First crash: 876d, last: 876d
Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __dentry_kill / step_into (6) fs 1 97d 97d 0/27 auto-obsoleted due to no activity on 2024/05/21 11:40
upstream KCSAN: data-race in __dentry_kill / step_into (8) fs 4 1d20h 21d 0/27 moderation: reported on 2024/07/01 14:35
upstream KCSAN: data-race in __dentry_kill / step_into fs 1 1381d 1381d 0/27 auto-closed as invalid on 2020/11/14 02:21
upstream KCSAN: data-race in __dentry_kill / step_into (5) fs 106 143d 227d 0/27 auto-obsoleted due to no activity on 2024/04/05 18:21
upstream KCSAN: data-race in __dentry_kill / step_into (7) fs 2 58d 62d 0/27 auto-obsoleted due to no activity on 2024/06/29 19:22
upstream KCSAN: data-race in __dentry_kill / step_into (2) fs 3 1137d 1174d 0/27 auto-closed as invalid on 2021/07/16 10:59
upstream KCSAN: data-race in __dentry_kill / step_into (3) fs 5 939d 996d 0/27 auto-closed as invalid on 2022/01/30 10:25

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

write to 0xffff88812f3bd480 of 4 bytes by task 20414 on cpu 0:
 dentry_unlist fs/dcache.c:547 [inline]
 __dentry_kill+0x147/0x450 fs/dcache.c:603
 dput+0x218/0x430 fs/dcache.c:913
 do_unlinkat+0x2a8/0x540 fs/namei.c:4221
 __do_sys_unlink fs/namei.c:4266 [inline]
 __se_sys_unlink fs/namei.c:4264 [inline]
 __x64_sys_unlink+0x2c/0x30 fs/namei.c:4264
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88812f3bd480 of 4 bytes by task 1438 on cpu 1:
 __d_entry_type include/linux/dcache.h:385 [inline]
 d_is_symlink include/linux/dcache.h:415 [inline]
 step_into+0x171/0xf70 fs/namei.c:1854
 walk_component+0x1a1/0x360 fs/namei.c:2026
 lookup_last fs/namei.c:2475 [inline]
 path_lookupat+0x12d/0x3d0 fs/namei.c:2499
 filename_lookup+0x130/0x310 fs/namei.c:2528
 user_path_at_empty+0x3e/0x110 fs/namei.c:2851
 do_readlinkat+0x97/0x210 fs/stat.c:443
 __do_sys_readlink fs/stat.c:476 [inline]
 __se_sys_readlink fs/stat.c:473 [inline]
 __x64_sys_readlink+0x43/0x50 fs/stat.c:473
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00600008 -> 0x00008008

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1438 Comm: udevd Not tainted 5.17.0-rc5-syzkaller-00306-g2293be58d6a1-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/02/27 02:15 upstream 2293be58d6a1 45a13a73 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / step_into
* Struck through repros no longer work on HEAD.