From: Miklos Szeredi <miklos@szeredi.hu>
This patch fixes a bug, that allowed multiple dentries to refer to the same
directory inode. This check was dropped from the 2.6 version probably because
I believed that d_splice_alias() will somehow do this check (which it
doesn't). Thanks to the fine folks on linux-fsdevel reminding me of the ugly
possibility of hardlinked directories.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
fs/fuse/dir.c | 9 +++++++++
1 files changed, 9 insertions(+)
diff -puN fs/fuse/dir.c~fuse-read-only-operations-multiple-links-to-directory-fix fs/fuse/dir.c
--- 25/fs/fuse/dir.c~fuse-read-only-operations-multiple-links-to-directory-fix Thu Apr 28 16:53:22 2005
+++ 25-akpm/fs/fuse/dir.c Thu Apr 28 16:53:22 2005
@@ -359,6 +359,15 @@ static struct dentry *fuse_lookup(struct
int err = fuse_lookup_iget(dir, entry, &inode);
if (err)
return ERR_PTR(err);
+ if (inode && S_ISDIR(inode->i_mode)) {
+ /* Don't allow creating an alias to a directory */
+ struct dentry *alias = d_find_alias(inode);
+ if (alias && !(alias->d_flags & DCACHE_DISCONNECTED)) {
+ dput(alias);
+ iput(inode);
+ return ERR_PTR(-EIO);
+ }
+ }
return d_splice_alias(inode, entry);
}
_