[review v3] core: REE FS: close dirfile on error

- Failure from get_dirh() results in *dirh = NULL
- put_dirh() with dirh == NULL is ignored

put_dirh() after failing get_dirh() isn't needed, but harmless if done
since dirh will be NULL.

Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

core/tee/tee_ree_fs.c

@@ -534,13 +534,15 @@ static void close_dirh(struct tee_fs_dirfile_dirh **dirh)
 
 static TEE_Result get_dirh(struct tee_fs_dirfile_dirh **dirh)
 {
-	ree_fs_dirh_refcount++;
 	if (!ree_fs_dirh) {
 		TEE_Result res = open_dirh(&ree_fs_dirh);
 
-		if (res)
+		if (res) {
+			*dirh = NULL;
 			return res;
+		}
 	}
+	ree_fs_dirh_refcount++;
 	assert(ree_fs_dirh);
 	assert(ree_fs_dirh_refcount);
 	*dirh = ree_fs_dirh;
@@ -550,6 +552,7 @@ static TEE_Result get_dirh(struct tee_fs_dirfile_dirh **dirh)
 static void put_dirh_primitive(bool close)
 {
 	assert(ree_fs_dirh_refcount);
+	assert(ree_fs_dirh);
 
 	ree_fs_dirh_refcount--;
 	if (!ree_fs_dirh_refcount || close)
@@ -558,8 +561,10 @@ static void put_dirh_primitive(bool close)
 
 static void put_dirh(struct tee_fs_dirfile_dirh *dirh, bool close)
 {
-	assert(!dirh || dirh == ree_fs_dirh);
-	put_dirh_primitive(close);
+	if (dirh) {
+		assert(dirh == ree_fs_dirh);
+		put_dirh_primitive(close);
+	}
 }
 
 static TEE_Result ree_fs_open(struct tee_pobj *po, size_t *size,