syzbot


KCSAN: data-race in d_invalidate / fast_dput (2)

Status: moderation: reported on 2024/06/04 14:03
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+93fd29c10343c5f02a57@syzkaller.appspotmail.com
First crash: 10d, last: 10d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in d_invalidate / fast_dput fs 4 83d 130d 0/27 auto-obsoleted due to no activity on 2024/04/27 15:57

Sample crash report:
==================================================================
BUG: KCSAN: data-race in d_invalidate / fast_dput

write to 0xffff88813286b910 of 8 bytes by task 1946 on cpu 1:
 __d_drop fs/dcache.c:509 [inline]
 d_invalidate+0x59/0x1c0 fs/dcache.c:1585
 lookup_fast+0x254/0x2a0 fs/namei.c:1657
 open_last_lookups fs/namei.c:3542 [inline]
 path_openat+0x44c/0x1da0 fs/namei.c:3804
 do_filp_open+0xf7/0x200 fs/namei.c:3834
 do_sys_openat2+0xab/0x120 fs/open.c:1405
 do_sys_open fs/open.c:1420 [inline]
 __do_sys_openat fs/open.c:1436 [inline]
 __se_sys_openat fs/open.c:1431 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1431
 x64_sys_call+0x1057/0x2d70 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 0xffff88813286b910 of 8 bytes by task 1947 on cpu 0:
 hlist_bl_unhashed include/linux/list_bl.h:54 [inline]
 d_unhashed include/linux/dcache.h:347 [inline]
 retain_dentry fs/dcache.c:686 [inline]
 fast_dput+0x62/0x2b0 fs/dcache.c:782
 dput+0x24/0xd0 fs/dcache.c:839
 path_put fs/namei.c:561 [inline]
 terminate_walk+0xfb/0x280 fs/namei.c:685
 path_openat+0x1821/0x1da0 fs/namei.c:3808
 do_filp_open+0xf7/0x200 fs/namei.c:3834
 do_sys_openat2+0xab/0x120 fs/open.c:1405
 do_sys_open fs/open.c:1420 [inline]
 __do_sys_openat fs/open.c:1436 [inline]
 __se_sys_openat fs/open.c:1431 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1431
 x64_sys_call+0x1057/0x2d70 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: 0xffff88823795fc30 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1947 Comm: syz-executor.0 Tainted: G        W          6.10.0-rc2-syzkaller-00010-g2ab795141095 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/04 14:02 upstream 2ab795141095 11f2afa5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in d_invalidate / fast_dput
* Struck through repros no longer work on HEAD.