efi_loader: error handling in efi_disk_add_dev

* If an error occurs in efi_disk_add_dev(), don't leak resources.
* If calloc() fails while creating the file system protocol interface,
  signal an error.
* Rename efi_simple_file_system() to efi_create_simple_file_system().
* Drop a little helpful debug message.

Fixes: 2a92080d8c44 ("efi_loader: add file/filesys support")
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

2 files changed, 17 insertions, 10 deletions

diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c
index 46cb5704a7..f0d76113b0 100644
--- a/lib/efi_loader/efi_disk.c
+++ b/lib/efi_loader/efi_disk.c
@@ -487,15 +487,16 @@ static efi_status_t efi_disk_add_dev(
 	 */
 	if ((part || desc->part_type == PART_TYPE_UNKNOWN) &&
 	    efi_fs_exists(desc, part)) {
-		diskobj->volume = efi_simple_file_system(desc, part,
-							 diskobj->dp);
+		ret = efi_create_simple_file_system(desc, part, diskobj->dp,
+						    &diskobj->volume);
+		if (ret != EFI_SUCCESS)
+			goto error;
+
 		ret = efi_add_protocol(&diskobj->header,
 				       &efi_simple_file_system_protocol_guid,
 				       diskobj->volume);
-		if (ret != EFI_SUCCESS) {
-			log_debug("simple FS failed\n");
-			return ret;
-		}
+		if (ret != EFI_SUCCESS)
+			goto error;
 	}
 	diskobj->ops = block_io_disk_template;
 	diskobj->dev_index = dev_index;
@@ -538,6 +539,8 @@ static efi_status_t efi_disk_add_dev(
 	return EFI_SUCCESS;
 error:
 	efi_delete_handle(&diskobj->header);
+	free(diskobj->volume);
+	free(diskobj);
 	return ret;
 }
 
diff --git a/lib/efi_loader/efi_file.c b/lib/efi_loader/efi_file.c
index 520c730220..3764a92b50 100644
--- a/lib/efi_loader/efi_file.c
+++ b/lib/efi_loader/efi_file.c
@@ -1192,18 +1192,22 @@ efi_open_volume(struct efi_simple_file_system_protocol *this,
 	return EFI_EXIT(efi_open_volume_int(this, root));
 }
 
-struct efi_simple_file_system_protocol *
-efi_simple_file_system(struct blk_desc *desc, int part,
-		       struct efi_device_path *dp)
+efi_status_t
+efi_create_simple_file_system(struct blk_desc *desc, int part,
+			      struct efi_device_path *dp,
+			      struct efi_simple_file_system_protocol **fsp)
 {
 	struct file_system *fs;
 
 	fs = calloc(1, sizeof(*fs));
+	if (!fs)
+		return EFI_OUT_OF_RESOURCES;
 	fs->base.rev = EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_REVISION;
 	fs->base.open_volume = efi_open_volume;
 	fs->desc = desc;
 	fs->part = part;
 	fs->dp = dp;
+	*fsp = &fs->base;
 
-	return &fs->base;
+	return EFI_SUCCESS;
 }