syzbot


KCSAN: data-race in __dentry_kill / lookup_fast (11)

Status: auto-obsoleted due to no activity on 2024/08/23 20:28
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+511f4cd1b47514ec3075@syzkaller.appspotmail.com
First crash: 50d, last: 50d
Similar bugs (10)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __dentry_kill / lookup_fast (5) fs 12 1195d 1268d 0/27 auto-closed as invalid on 2021/07/05 09:49
upstream KCSAN: data-race in __dentry_kill / lookup_fast (8) fs 8 506d 570d 0/27 auto-obsoleted due to no activity on 2023/05/25 00:07
upstream KCSAN: data-race in __dentry_kill / lookup_fast (2) fs 5 1476d 1536d 0/27 auto-closed as invalid on 2020/09/27 09:27
upstream KCSAN: data-race in __dentry_kill / lookup_fast fs 10 1559d 1652d 0/27 closed as invalid on 2020/06/18 14:24
upstream KCSAN: data-race in __dentry_kill / lookup_fast (10) fs 3 160d 198d 0/27 auto-obsoleted due to no activity on 2024/05/05 12:07
upstream KCSAN: data-race in __dentry_kill / lookup_fast (7) fs 27 617d 877d 0/27 auto-obsoleted due to no activity on 2023/02/12 11:35
upstream KCSAN: data-race in __dentry_kill / lookup_fast (6) fs 1 1022d 1022d 0/27 auto-closed as invalid on 2021/12/25 02:52
upstream KCSAN: data-race in __dentry_kill / lookup_fast (4) fs 3 1316d 1341d 0/27 auto-closed as invalid on 2021/03/06 20:57
upstream KCSAN: data-race in __dentry_kill / lookup_fast (3) fs 3 1378d 1370d 0/27 auto-closed as invalid on 2021/01/03 16:37
upstream KCSAN: data-race in __dentry_kill / lookup_fast (9) fs 31 238d 273d 0/27 auto-obsoleted due to no activity on 2024/02/17 10:11

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

read-write to 0xffff888106a72240 of 4 bytes by task 16413 on cpu 1:
 dentry_unlist fs/dcache.c:555 [inline]
 __dentry_kill+0x22e/0x4c0 fs/dcache.c:624
 dput+0x5c/0xd0 fs/dcache.c:852
 path_put fs/namei.c:568 [inline]
 terminate_walk+0xfb/0x280 fs/namei.c:692
 path_openat+0x1979/0x1f10 fs/namei.c:3887
 do_filp_open+0xf7/0x200 fs/namei.c:3913
 do_sys_openat2+0xab/0x120 fs/open.c:1416
 do_sys_open fs/open.c:1431 [inline]
 __do_sys_openat fs/open.c:1447 [inline]
 __se_sys_openat fs/open.c:1442 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1442
 x64_sys_call+0x1ac/0x2e00 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888106a72240 of 4 bytes by task 16412 on cpu 0:
 d_revalidate fs/namei.c:867 [inline]
 lookup_fast+0xd9/0x2a0 fs/namei.c:1667
 open_last_lookups fs/namei.c:3615 [inline]
 path_openat+0x466/0x1f10 fs/namei.c:3883
 do_filp_open+0xf7/0x200 fs/namei.c:3913
 do_sys_openat2+0xab/0x120 fs/open.c:1416
 do_sys_open fs/open.c:1431 [inline]
 __do_sys_openat fs/open.c:1447 [inline]
 __se_sys_openat fs/open.c:1442 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1442
 x64_sys_call+0x1ac/0x2e00 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0040000c -> 0x0000800c

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 16412 Comm: syz.4.3635 Not tainted 6.10.0-syzkaller-09061-g4305ca0087dd #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/19 20:27 upstream 4305ca0087dd 890ce4f3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / lookup_fast
* Struck through repros no longer work on HEAD.