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KCSAN: data-race in __dentry_kill / step_into

Status: auto-closed as invalid on 2020/11/14 02:21
Subsystems: fs
[Documentation on labels]
First crash: 1381d, last: 1381d
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 1d21h 21d 0/27 moderation: reported on 2024/07/01 14:35
upstream KCSAN: data-race in __dentry_kill / step_into (5) fs 106 143d 228d 0/27 auto-obsoleted due to no activity on 2024/04/05 18:21
upstream KCSAN: data-race in __dentry_kill / step_into (4) fs 1 876d 876d 0/27 auto-closed as invalid on 2022/04/03 02:19
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 997d 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 0xffff88806f143480 of 4 bytes by task 23140 on cpu 0:
 dentry_unlist fs/dcache.c:519 [inline]
 __dentry_kill+0x147/0x450 fs/dcache.c:575
 dentry_kill fs/dcache.c:692 [inline]
 dput+0x208/0x420 fs/dcache.c:878
 do_unlinkat+0x298/0x4d0 fs/namei.c:3898
 __do_sys_unlink fs/namei.c:3942 [inline]
 __se_sys_unlink fs/namei.c:3940 [inline]
 __x64_sys_unlink+0x2c/0x30 fs/namei.c:3940
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88806f143480 of 4 bytes by task 5079 on cpu 1:
 __follow_mount_rcu fs/namei.c:1316 [inline]
 handle_mounts fs/namei.c:1373 [inline]
 step_into+0xec/0xe70 fs/namei.c:1690
 walk_component+0x190/0x350 fs/namei.c:1866
 lookup_last fs/namei.c:2309 [inline]
 path_lookupat+0x12d/0x560 fs/namei.c:2333
 filename_lookup+0xf2/0x380 fs/namei.c:2366
 user_path_at_empty+0x3b/0x50 fs/namei.c:2646
 do_readlinkat+0x87/0x200 fs/stat.c:419
 __do_sys_readlink fs/stat.c:452 [inline]
 __se_sys_readlink fs/stat.c:449 [inline]
 __x64_sys_readlink+0x43/0x50 fs/stat.c:449
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 5079 Comm: systemd-udevd Not tainted 5.9.0-rc8-syzkaller #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
2020/10/10 02:21 upstream 8a5f78d98c26 93817d89 .config console log report info ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.