syzbot


KCSAN: data-race in __d_lookup_done / __dentry_kill (3)

Status: auto-closed as invalid on 2020/11/08 00:33
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 680d, last: 680d
similar bugs (5):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __d_lookup_done / __dentry_kill (5) 5 438d 473d 0/23 auto-closed as invalid on 2021/07/08 04:16
upstream KCSAN: data-race in __d_lookup_done / __dentry_kill (4) 3 559d 583d 0/23 auto-closed as invalid on 2021/03/09 07:41
upstream KCSAN: data-race in __d_lookup_done / __dentry_kill (6) 1 113d 113d 0/23 auto-closed as invalid on 2022/05/29 05:25
upstream KCSAN: data-race in __d_lookup_done / __dentry_kill (2) 4 762d 781d 0/23 auto-closed as invalid on 2020/08/18 04:12
upstream KCSAN: data-race in __d_lookup_done / __dentry_kill 29 848d 1022d 0/23 auto-closed as invalid on 2020/06/18 14:14

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

write to 0xffff8880a4f336c0 of 4 bytes by task 5076 on cpu 1:
 __d_lookup_done+0x8e/0x240 fs/dcache.c:2648
 d_lookup_done include/linux/dcache.h:369 [inline]
 __lookup_slow+0x206/0x250 fs/namei.c:1545
 lookup_slow fs/namei.c:1561 [inline]
 walk_component+0x2a5/0x350 fs/namei.c:1860
 link_path_walk+0x462/0x730 fs/namei.c:2179
 path_lookupat+0x7b/0x560 fs/namei.c:2332
 filename_lookup+0xf2/0x380 fs/namei.c:2366
 user_path_at_empty+0x3b/0x50 fs/namei.c:2646
 user_path_at include/linux/namei.h:59 [inline]
 do_faccessat+0x260/0x500 fs/open.c:423
 __do_sys_access fs/open.c:482 [inline]
 __se_sys_access fs/open.c:480 [inline]
 __x64_sys_access+0x33/0x40 fs/open.c:480
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8880a4f336c0 of 4 bytes by task 25409 on cpu 0:
 dentry_unlist fs/dcache.c:544 [inline]
 __dentry_kill+0x1ef/0x450 fs/dcache.c:575
 dentry_kill fs/dcache.c:692 [inline]
 dput+0x208/0x420 fs/dcache.c:878
 handle_mounts fs/namei.c:1389 [inline]
 step_into+0x448/0xe70 fs/namei.c:1690
 walk_component+0x190/0x350 fs/namei.c:1866
 link_path_walk+0x462/0x730 fs/namei.c:2179
 path_lookupat+0x7b/0x560 fs/namei.c:2332
 filename_lookup+0xf2/0x380 fs/namei.c:2366
 user_path_at_empty+0x3b/0x50 fs/namei.c:2646
 user_path_at include/linux/namei.h:59 [inline]
 do_faccessat+0x260/0x500 fs/open.c:423
 __do_sys_access fs/open.c:482 [inline]
 __se_sys_access fs/open.c:480 [inline]
 __x64_sys_access+0x33/0x40 fs/open.c:480
 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: 0 PID: 25409 Comm: systemd-rfkill Not tainted 5.9.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2020/10/04 00:32 upstream 22fbc037cd32 1a3f9408 .config log report info