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KCSAN: data-race in link_path_walk / vfs_rmdir

Status: auto-closed as invalid on 2020/09/11 12:18
Subsystems: fs
[Documentation on labels]
First crash: 1357d, last: 1357d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in link_path_walk / vfs_rmdir (2) fs 1 1078d 1078d 0/26 auto-closed as invalid on 2021/06/17 14:31
upstream KCSAN: data-race in link_path_walk / vfs_rmdir (3) fs 1 957d 957d 0/26 auto-closed as invalid on 2021/10/16 11:56

Sample crash report:
==================================================================
BUG: KCSAN: data-race in link_path_walk / vfs_rmdir

write to 0xffff888115c13c00 of 4 bytes by task 13937 on cpu 0:
 dont_mount include/linux/dcache.h:354 [inline]
 vfs_rmdir+0x1a6/0x2a0 fs/namei.c:3710
 do_rmdir+0x170/0x320 fs/namei.c:3766
 __do_sys_rmdir fs/namei.c:3784 [inline]
 __se_sys_rmdir fs/namei.c:3782 [inline]
 __x64_sys_rmdir+0x20/0x30 fs/namei.c:3782
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888115c13c00 of 4 bytes by task 13942 on cpu 1:
 __d_entry_type include/linux/dcache.h:391 [inline]
 d_can_lookup include/linux/dcache.h:406 [inline]
 link_path_walk+0x47e/0x730 fs/namei.c:2193
 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
 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: 13942 Comm: systemd-udevd Not tainted 5.8.0-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
2020/08/07 12:10 upstream 86cfccb66937 28ac5c9e .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.