| Summary: | rmdir shows wrong behaviour when trying to remove a mountpoint | ||
|---|---|---|---|
| Product: | [Retired] Red Hat Linux | Reporter: | Dmitry Pugachov <dima_p> |
| Component: | kernel | Assignee: | Michael K. Johnson <johnsonm> |
| Status: | CLOSED CURRENTRELEASE | QA Contact: | |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 6.1 | ||
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | i386 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2000-01-17 13:49:11 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
When rmdir() is called with a mounpoint (directory with a mounted filesystem) name as the argument, it returns ENOENT error code. It appears that there is a bug in the do_rmdir() routine (fs/namei.c module): ........... dentry = lookup_dentry(name, NULL, 0); ........... dir = dget(dentry->d_parent); ........... error = -ENOENT; if (check_parent(dir, dentry)) error = vfs_rmdir(dir->d_inode, dentry); ........... lookup_dentry() will return the dentry for the root of the mounted filesystem, thus resulting in that dir will be the same as dentry (d_parent field of "/" points to itself). After that, check_parent() will fail (because dir == dentry), and ENOENT will be returned. Clearly, "no such file or directory" is not the right way to tell the user that she's trying to rmdir() a mountpoint. Changing check_parent() to: #define check_parent(dir, dentry) \ ((dir) == (dentry) || (dir) == (dentry)->d_parent && !list_empty(&dentry->d_hash)) fixes the problem, but that might cause some trouble with parent locking, or am I wrong?