efi_loader: fix 'efidebug boot dump'

* Do not recreate a variable name that we already have as u16 string.
* Check the return value of malloc()
* EFI_NOT_FOUND cannot occur for a variable name returned by
  GetNextVariableName(). Remove a print statement.
* Don't copy a GUID for no reason.
* Don't use the run-time service table to call exported functions.
* Don't pass NULL to show_efi_boot_opt_data() (fixes Coverity CID 300338).

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

1 files changed, 20 insertions, 25 deletions

diff --git a/cmd/efidebug.c b/cmd/efidebug.c
index 02ef019694..7ff2ce4ce1 100644
--- a/cmd/efidebug.c
+++ b/cmd/efidebug.c
@@ -682,13 +682,13 @@ static int do_efi_boot_rm(cmd_tbl_t *cmdtp, int flag,
 /**
  * show_efi_boot_opt_data() - dump UEFI load option
  *
- * @id:		load option number
+ * @varname16:	variable name
  * @data:	value of UEFI load option variable
  * @size:	size of the boot option
  *
  * Decode the value of UEFI load option variable and print information.
  */
-static void show_efi_boot_opt_data(int id, void *data, size_t size)
+static void show_efi_boot_opt_data(u16 *varname16, void *data, size_t size)
 {
 	struct efi_load_option lo;
 	char *label, *p;
@@ -705,8 +705,8 @@ static void show_efi_boot_opt_data(int id, void *data, size_t size)
 	p = label;
 	utf16_utf8_strncpy(&p, lo.label, label_len16);
 
-	printf("Boot%04X:\n", id);
-	printf("  attributes: %c%c%c (0x%08x)\n",
+	printf("%ls:\nattributes: %c%c%c (0x%08x)\n",
+	       varname16,
 	       /* ACTIVE */
 	       lo.attributes & LOAD_OPTION_ACTIVE ? 'A' : '-',
 	       /* FORCE RECONNECT */
@@ -730,37 +730,32 @@ static void show_efi_boot_opt_data(int id, void *data, size_t size)
 /**
  * show_efi_boot_opt() - dump UEFI load option
  *
- * @id:		Load option number
+ * @varname16:	variable name
  *
  * Dump information defined by UEFI load option.
  */
-static void show_efi_boot_opt(int id)
+static void show_efi_boot_opt(u16 *varname16)
 {
-	char var_name[9];
-	u16 var_name16[9], *p;
-	efi_guid_t guid;
-	void *data = NULL;
+	void *data;
 	efi_uintn_t size;
 	efi_status_t ret;
 
-	sprintf(var_name, "Boot%04X", id);
-	p = var_name16;
-	utf8_utf16_strncpy(&p, var_name, 9);
-	guid = efi_global_variable_guid;
-
 	size = 0;
-	ret = EFI_CALL(RT->get_variable(var_name16, &guid, NULL, &size, NULL));
+	ret = EFI_CALL(efi_get_variable(varname16, &efi_global_variable_guid,
+					NULL, &size, NULL));
 	if (ret == EFI_BUFFER_TOO_SMALL) {
 		data = malloc(size);
-		ret = EFI_CALL(RT->get_variable(var_name16, &guid, NULL, &size,
-						data));
+		if (!data) {
+			printf("ERROR: Out of memory\n");
+			return;
+		}
+		ret = EFI_CALL(efi_get_variable(varname16,
+						&efi_global_variable_guid,
+						NULL, &size, data));
+		if (ret == EFI_SUCCESS)
+			show_efi_boot_opt_data(varname16, data, size);
+		free(data);
 	}
-	if (ret == EFI_SUCCESS)
-		show_efi_boot_opt_data(id, data, size);
-	else if (ret == EFI_NOT_FOUND)
-		printf("Boot%04X: not found\n", id);
-
-	free(data);
 }
 
 static int u16_tohex(u16 c)
@@ -839,7 +834,7 @@ static int do_efi_boot_dump(cmd_tbl_t *cmdtp, int flag,
 			id = (id << 4) + digit;
 		}
 		if (i == 4 && !var_name16[8])
-			show_efi_boot_opt(id);
+			show_efi_boot_opt(var_name16);
 	}
 
 	free(var_name16);