syzbot

 sign-in | mailing list | source | docs
🐞 Open [1496]
≡ Subsystems
🐞 Fixed [6583]
🐞 Invalid [16838]
⬇ Missing Backports [204]
≡ Crashes
Kernel Health Bugs/Month Bug Lifetimes Fuzzing
Total Repo Heatmap Subsystems Heatmap
💬 Send us feedback

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

Status: auto-closed as invalid on 2021/06/09 01:27
Subsystems: fs
[Documentation on labels]
First crash: 1595d, last: 1595d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __dentry_kill / d_alloc_parallel fs 6 36 2052d 2155d 0/29 auto-closed as invalid on 2020/04/13 06:40
upstream KCSAN: data-race in __dentry_kill / d_alloc_parallel (2) fs 6 3 1872d 1903d 0/29 auto-closed as invalid on 2020/09/05 03:58
upstream KCSAN: data-race in __dentry_kill / d_alloc_parallel (5) fs 6 1 74d 74d 0/29 auto-obsoleted due to no activity on 2025/08/29 10:09
upstream KCSAN: data-race in __dentry_kill / d_alloc_parallel (3) fs 6 1 1836d 1836d 0/29 auto-closed as invalid on 2020/10/11 15:50

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

write to 0xffff8881848b1000 of 4 bytes by task 26298 on cpu 1:
 d_alloc_parallel+0x9d7/0xba0 fs/dcache.c:2666
 lookup_open fs/namei.c:3139 [inline]
 open_last_lookups fs/namei.c:3285 [inline]
 path_openat+0x659/0x20b0 fs/namei.c:3491
 do_filp_open+0xd9/0x1f0 fs/namei.c:3521
 do_sys_openat2+0xa3/0x250 fs/open.c:1187
 do_sys_open fs/open.c:1203 [inline]
 __do_sys_open fs/open.c:1211 [inline]
 __se_sys_open fs/open.c:1207 [inline]
 __x64_sys_open+0xe2/0x110 fs/open.c:1207
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881848b1000 of 4 bytes by task 26323 on cpu 0:
 dentry_unlist fs/dcache.c:547 [inline]
 __dentry_kill+0x1ef/0x4e0 fs/dcache.c:578
 dentry_kill fs/dcache.c:695 [inline]
 dput+0xc6/0x360 fs/dcache.c:888
 handle_mounts fs/namei.c:1474 [inline]
 step_into+0x442/0xec0 fs/namei.c:1772
 open_last_lookups fs/namei.c:3308 [inline]
 path_openat+0xfc8/0x20b0 fs/namei.c:3491
 do_filp_open+0xd9/0x1f0 fs/namei.c:3521
 do_sys_openat2+0xa3/0x250 fs/open.c:1187
 do_sys_open fs/open.c:1203 [inline]
 __do_sys_open fs/open.c:1211 [inline]
 __se_sys_open fs/open.c:1207 [inline]
 __x64_sys_open+0xe2/0x110 fs/open.c:1207
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 26323 Comm: systemd-udevd Not tainted 5.12.0-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
2021/05/05 01:23 upstream 5e321ded302d 06c27ff5 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / d_alloc_parallel
* Struck through repros no longer work on HEAD.