[PATCH] quota: sanitize dentry handling in vfs_quota_on_mount

Use lookup_one_len instead of opencoding a simplified lookup using
lookup_hash with a fake hash.

Also there's no need anymore for the d_invalidate as we have a completely
valid dentry now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/dquot.c b/fs/dquot.c
index 343c036..37212b0 100644 (file)
--- a/fs/dquot.c
+++ b/fs/dquot.c
@@ -1522,11 +1522,10 @@ out_path:
 int vfs_quota_on_mount(struct super_block *sb, char *qf_name,
                int format_id, int type)
 {
-       struct qstr name = {.name = qf_name, .len = 0, .len = strlen(qf_name)};
        struct dentry *dentry;
        int error;
 
-       dentry = lookup_hash(&name, sb->s_root);
+       dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name));
        if (IS_ERR(dentry))
                return PTR_ERR(dentry);
 
@@ -1534,12 +1533,6 @@ int vfs_quota_on_mount(struct super_block *sb, char *qf_name,
        if (!error)
                error = vfs_quota_on_inode(dentry->d_inode, type, format_id);
 
-       /*
-        * Now invalidate and put the dentry - quota got its own reference
-        * to inode and dentry has at least wrong hash so we had better
-        * throw it away.
-        */
-       d_invalidate(dentry);
        dput(dentry);
        return error;
 }