[PATCH] kNFSd: NFSv4: fix type checking in fh_verify()

Change the type checking in fh_verify().  This fixes a bug which
I reported on the mailing list a few days ago, and also adds a
new error code nfserr_symlink (v4 only).  This is returned whenever
an operation which is illegal for symlinks is attempted on a symlink,
and takes precedence over ERR_NOTDIR or ERR_INVAL.

fs/nfsd/nfsfh.c

@@ -234,11 +234,23 @@ fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, int access)
 
 	/* Type can be negative when creating hardlinks - not to a dir */
 	if (type > 0 && (inode->i_mode & S_IFMT) != type) {
-		error = (type == S_IFDIR)? nfserr_notdir : nfserr_isdir;
+		if (rqstp->rq_vers == 4 && (inode->i_mode & S_IFMT) == S_IFLNK)
+			error = nfserr_symlink;
+		else if (type == S_IFDIR)
+			error = nfserr_notdir;
+		else if ((inode->i_mode & S_IFMT) == S_IFDIR)
+			error = nfserr_isdir;
+		else
+			error = nfserr_inval;
 		goto out;
 	}
 	if (type < 0 && (inode->i_mode & S_IFMT) == -type) {
-		error = (type == -S_IFDIR)? nfserr_notdir : nfserr_isdir;
+		if (rqstp->rq_vers == 4 && (inode->i_mode & S_IFMT) == S_IFLNK)
+			error = nfserr_symlink;
+		else if (type == -S_IFDIR)
+			error = nfserr_isdir;
+		else
+			error = nfserr_notdir;
 		goto out;
 	}