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KCSAN: data-race in link_path_walk / vfs_rmdir (3)

Status: auto-closed as invalid on 2021/10/16 11:56
Subsystems: fs
[Documentation on labels]
First crash: 929d, last: 929d
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 fs 1 1329d 1329d 0/26 auto-closed as invalid on 2020/09/11 12:18
upstream KCSAN: data-race in link_path_walk / vfs_rmdir (2) fs 1 1050d 1050d 0/26 auto-closed as invalid on 2021/06/17 14:31

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

write to 0xffff88813803ccc0 of 4 bytes by task 17018 on cpu 1:
 dont_mount include/linux/dcache.h:358 [inline]
 vfs_rmdir+0x1ac/0x300 fs/namei.c:3976
 do_rmdir+0x18d/0x340 fs/namei.c:4032
 __do_sys_rmdir fs/namei.c:4051 [inline]
 __se_sys_rmdir fs/namei.c:4049 [inline]
 __x64_sys_rmdir+0x2c/0x30 fs/namei.c:4049
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88813803ccc0 of 4 bytes by task 1 on cpu 0:
 __d_entry_type include/linux/dcache.h:395 [inline]
 d_can_lookup include/linux/dcache.h:410 [inline]
 link_path_walk+0x4cb/0x770 fs/namei.c:2307
 path_lookupat+0x8b/0x3d0 fs/namei.c:2448
 __filename_lookup+0x130/0x310 fs/namei.c:2478
 filename_lookup fs/namei.c:2494 [inline]
 user_path_at_empty+0x3e/0x110 fs/namei.c:2801
 user_path_at include/linux/namei.h:57 [inline]
 vfs_statx+0xa9/0x2a0 fs/stat.c:221
 vfs_fstatat fs/stat.c:243 [inline]
 vfs_stat include/linux/fs.h:3352 [inline]
 __do_sys_newstat fs/stat.c:385 [inline]
 __se_sys_newstat+0x5d/0x250 fs/stat.c:381
 __x64_sys_newstat+0x2d/0x40 fs/stat.c:381
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00200008 -> 0x00008008

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1 Comm: systemd Tainted: G        W         5.14.0-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
2021/09/11 11:47 upstream 926de8c4326c 3ce60af8 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in link_path_walk / vfs_rmdir
* Struck through repros no longer work on HEAD.