[U-Boot] [PATCH v6 0/1] cmd: env: extend "env [set|print] -e" to manage UEFI variables

[U-Boot] [PATCH v6 0/1] cmd: env: extend "env [set|print] -e" to manage UEFI variables

[AKASHI Takahiro]

This is my sixth version of "env -e" extension.

Changes in v6 (Oct 24, 2019)
* change default action of "env print -e" to dumping variables' values.
  Meanwhile a new "-n" option will suppress it.
* improve an error message for wrong guid format
* remove all the checks against option parameters as they are far from
  perfect and quite arguable. They will be checked any way in API call.

Changes in v5 (Oct 15, 2019)
* improve a message in case of wrong guid format
* improve a message in case that BOOTSERVICE_ACCESS is required

Changes in v4 (Oct 7, 2019)
* print usage message if "-guid guid" has a wrong format
* add "-guid guid"  and "-all" option to "env print -e" command
  to specify a specific guid (or any guids)

Changes in v3 (Oct 4, 2019)
* add verbose messages when SetVariable() fails
* add "-v" option

Changes in v2 (Sept 6, 2019)
* remove "-at" option

AKASHI Takahiro (1):
  cmd: env: extend "env [set|print] -e" to manage UEFI variables

 cmd/nvedit.c     |  19 +++-
 cmd/nvedit_efi.c | 277 ++++++++++++++++++++++++++++++++++++++++-------
 2 files changed, 252 insertions(+), 44 deletions(-)

-- 
2.21.0

[U-Boot] [PATCH v6 1/1] cmd: env: extend "env [set|print] -e" to manage UEFI variables

[AKASHI Takahiro]

With this patch, when setting UEFI variable with "env set -e" command,
we will be able to
- specify vendor guid with "-guid guid",
- specify variable attributes,  BOOTSERVICE_ACCESS, RUNTIME_ACCESS,
  respectively with "-bs" and "-rt",
- append a value instead of overwriting with "-a",
- use memory as variable's value instead of explicit values given
  at the command line with "-i address,size"

If guid is not explicitly given, default value will be used.

Meanwhile, "env print -e," will be modified so that it will NOT dump
a variable's value if '-n' is specified.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
---
 cmd/nvedit.c     |  19 +++-
 cmd/nvedit_efi.c | 277 ++++++++++++++++++++++++++++++++++++++++-------
 2 files changed, 252 insertions(+), 44 deletions(-)

diff --git a/cmd/nvedit.c b/cmd/nvedit.c
index 1cb0bc1460b9..99a3bc57b15f 100644
--- a/cmd/nvedit.c
+++ b/cmd/nvedit.c
@@ -1387,7 +1387,7 @@ static char env_help_text[] =
 #endif
 	"env print [-a | name ...] - print environment\n"
 #if defined(CONFIG_CMD_NVEDIT_EFI)
-	"env print -e [name ...] - print UEFI environment\n"
+	"env print -e [-guid guid|-all][-n] [name ...] - print UEFI environment\n"
 #endif
 #if defined(CONFIG_CMD_RUN)
 	"env run var [...] - run commands in an environment variable\n"
@@ -1399,7 +1399,8 @@ static char env_help_text[] =
 #endif
 #endif
 #if defined(CONFIG_CMD_NVEDIT_EFI)
-	"env set -e name [arg ...] - set UEFI variable; unset if 'arg' not specified\n"
+	"env set -e [-nv][-bs][-rt][-a][-i addr,size][-v] name [arg ...]\n"
+	"    - set UEFI variable; unset if '-i' or 'arg' not specified\n"
 #endif
 	"env set [-f] name [arg ...]\n";
 #endif
@@ -1428,8 +1429,9 @@ U_BOOT_CMD_COMPLETE(
 	"print environment variables",
 	"[-a]\n    - print [all] values of all environment variables\n"
 #if defined(CONFIG_CMD_NVEDIT_EFI)
-	"printenv -e [name ...]\n"
+	"printenv -e [-guid guid|-all][-n] [name ...]\n"
 	"    - print UEFI variable 'name' or all the variables\n"
+	"      \"-n\": suppress dumping variable's value\n"
 #endif
 	"printenv name ...\n"
 	"    - print value of environment variable 'name'",
@@ -1459,9 +1461,16 @@ U_BOOT_CMD_COMPLETE(
 	setenv, CONFIG_SYS_MAXARGS, 0,	do_env_set,
 	"set environment variables",
 #if defined(CONFIG_CMD_NVEDIT_EFI)
-	"-e [-nv] name [value ...]\n"
+	"-e [-guid guid][-nv][-bs][-rt][-a][-v]\n"
+	"        [-i addr,size name], or [name [value ...]]\n"
 	"    - set UEFI variable 'name' to 'value' ...'\n"
-	"      'nv' option makes the variable non-volatile\n"
+	"      \"-guid\": set vendor guid\n"
+	"      \"-nv\": set non-volatile attribute\n"
+	"      \"-bs\": set boot-service attribute\n"
+	"      \"-rt\": set runtime attribute\n"
+	"      \"-a\": append-write\n"
+	"      \"-i addr,size\": use <addr,size> as variable's value\n"
+	"      \"-v\": verbose message\n"
 	"    - delete UEFI variable 'name' if 'value' not specified\n"
 #endif
 	"setenv [-f] name value ...\n"
diff --git a/cmd/nvedit_efi.c b/cmd/nvedit_efi.c
index ed6d09a53046..333f286ed526 100644
--- a/cmd/nvedit_efi.c
+++ b/cmd/nvedit_efi.c
@@ -13,6 +13,7 @@
 #include <exports.h>
 #include <hexdump.h>
 #include <malloc.h>
+#include <mapmem.h>
 #include <linux/kernel.h>
 
 /*
@@ -34,15 +35,49 @@ static const struct {
 	{EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS, "AT"},
 };
 
+static const struct {
+	efi_guid_t guid;
+	char *text;
+} efi_guid_text[] = {
+	/* signature database */
+	{EFI_GLOBAL_VARIABLE_GUID, "EFI_GLOBAL_VARIABLE_GUID"},
+};
+
+/* "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" */
+static char unknown_guid[37];
+
+/**
+ * efi_guid_to_str() - convert guid to readable name
+ *
+ * @guid:	GUID
+ * Return:	string for GUID
+ *
+ * convert guid to readable name
+ */
+static const char *efi_guid_to_str(const efi_guid_t *guid)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(efi_guid_text); i++)
+		if (!guidcmp(guid, &efi_guid_text[i].guid))
+			return efi_guid_text[i].text;
+
+	uuid_bin_to_str((unsigned char *)guid->b, unknown_guid,
+			UUID_STR_FORMAT_GUID);
+
+	return unknown_guid;
+}
+
 /**
  * efi_dump_single_var() - show information about a UEFI variable
  *
  * @name:	Name of the variable
  * @guid:	Vendor GUID
+ * @verbose:	if true, dump data
  *
  * Show information encoded in one UEFI variable
  */
-static void efi_dump_single_var(u16 *name, efi_guid_t *guid)
+static void efi_dump_single_var(u16 *name, const efi_guid_t *guid, bool verbose)
 {
 	u32 attributes;
 	u8 *data;
@@ -68,7 +103,7 @@ static void efi_dump_single_var(u16 *name, efi_guid_t *guid)
 	if (ret != EFI_SUCCESS)
 		goto out;
 
-	printf("%ls:", name);
+	printf("%ls:\n    %s:", name, efi_guid_to_str(guid));
 	for (count = 0, i = 0; i < ARRAY_SIZE(efi_var_attrs); i++)
 		if (attributes & efi_var_attrs[i].mask) {
 			if (count)
@@ -79,7 +114,9 @@ static void efi_dump_single_var(u16 *name, efi_guid_t *guid)
 			puts(efi_var_attrs[i].text);
 		}
 	printf(", DataSize = 0x%zx\n", size);
-	print_hex_dump("    ", DUMP_PREFIX_OFFSET, 16, 1, data, size, true);
+	if (verbose)
+		print_hex_dump("    ", DUMP_PREFIX_OFFSET, 16, 1,
+			       data, size, true);
 
 out:
 	free(data);
@@ -90,11 +127,13 @@ out:
  *
  * @argc:	Number of arguments (variables)
  * @argv:	Argument (variable name) array
+ * @verbose:	if true, dump data
  * Return:	CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
  *
  * Show information encoded in named UEFI variables
  */
-static int efi_dump_vars(int argc,  char * const argv[])
+static int efi_dump_vars(int argc,  char * const argv[],
+			 const efi_guid_t *guid, bool verbose)
 {
 	u16 *var_name16, *p;
 	efi_uintn_t buf_size, size;
@@ -119,8 +158,7 @@ static int efi_dump_vars(int argc,  char * const argv[])
 		p = var_name16;
 		utf8_utf16_strcpy(&p, argv[0]);
 
-		efi_dump_single_var(var_name16,
-				    (efi_guid_t *)&efi_global_variable_guid);
+		efi_dump_single_var(var_name16, guid, verbose);
 	}
 
 	free(var_name16);
@@ -128,20 +166,56 @@ static int efi_dump_vars(int argc,  char * const argv[])
 	return CMD_RET_SUCCESS;
 }
 
+static bool match_name(int argc, char * const argv[], u16 *var_name16)
+{
+	char *buf, *p;
+	size_t buflen;
+	int i;
+	bool result = false;
+
+	buflen = utf16_utf8_strlen(var_name16) + 1;
+	buf = calloc(1, buflen);
+	if (!buf)
+		return result;
+
+	p = buf;
+	utf16_utf8_strcpy(&p, var_name16);
+
+	for (i = 0; i < argc; argc--, argv++) {
+		if (!strcmp(buf, argv[i])) {
+			result = true;
+			goto out;
+		}
+	}
+
+out:
+	free(buf);
+
+	return result;
+}
+
 /**
- * efi_dump_vars() - show information about all the UEFI variables
+ * efi_dump_var_all() - show information about all the UEFI variables
  *
+ * @argc:	Number of arguments (variables)
+ * @argv:	Argument (variable name) array
+ * @verbose:	if true, dump data
  * Return:	CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
  *
  * Show information encoded in all the UEFI variables
  */
-static int efi_dump_var_all(void)
+static int efi_dump_var_all(int argc,  char * const argv[],
+			    const efi_guid_t *guid_p, bool verbose)
 {
 	u16 *var_name16, *p;
 	efi_uintn_t buf_size, size;
 	efi_guid_t guid;
 	efi_status_t ret;
 
+	if (argc && guid_p)
+		/* simplified case */
+		return efi_dump_vars(argc, argv, guid_p, verbose);
+
 	buf_size = 128;
 	var_name16 = malloc(buf_size);
 	if (!var_name16)
@@ -171,7 +245,9 @@ static int efi_dump_var_all(void)
 			return CMD_RET_FAILURE;
 		}
 
-		efi_dump_single_var(var_name16, &guid);
+		if ((!guid_p || !guidcmp(guid_p, &guid)) &&
+		    (!argc || match_name(argc, argv, var_name16)))
+			efi_dump_single_var(var_name16, &guid, verbose);
 	}
 
 	free(var_name16);
@@ -189,12 +265,15 @@ static int efi_dump_var_all(void)
  * Return:	CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
  *
  * This function is for "env print -e" or "printenv -e" command:
- *   => env print -e [var [...]]
+ *   => env print -e [-n] [-guid <guid> | -all] [var [...]]
  * If one or more variable names are specified, show information
  * named UEFI variables, otherwise show all the UEFI variables.
  */
 int do_env_print_efi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
+	efi_guid_t guid;
+	const efi_guid_t *guid_p;
+	bool default_guid, guid_any, verbose;
 	efi_status_t ret;
 
 	/* Initialize EFI drivers */
@@ -205,12 +284,47 @@ int do_env_print_efi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 		return CMD_RET_FAILURE;
 	}
 
-	if (argc > 1)
-		/* show specified UEFI variables */
-		return efi_dump_vars(--argc, ++argv);
+	default_guid = true;
+	guid_any = false;
+	verbose = true;
+	for (argc--, argv++; argc > 0 && argv[0][0] == '-'; argc--, argv++) {
+		if (!strcmp(argv[0], "-guid")) {
+			if (argc == 1)
+				return CMD_RET_USAGE;
+
+			/* -a already specified */
+			if (!default_guid & guid_any)
+				return CMD_RET_USAGE;
+
+			argc--;
+			argv++;
+			if (uuid_str_to_bin(argv[0], guid.b,
+					    UUID_STR_FORMAT_GUID))
+				return CMD_RET_USAGE;
+			default_guid = false;
+		} else if (!strcmp(argv[0], "-all")) {
+			/* -guid already specified */
+			if (!default_guid && !guid_any)
+				return CMD_RET_USAGE;
+
+			guid_any = true;
+			default_guid = false;
+		} else if (!strcmp(argv[0], "-n")) {
+			verbose = false;
+		} else {
+			return CMD_RET_USAGE;
+		}
+	}
+
+	if (guid_any)
+		guid_p = NULL;
+	else if (default_guid)
+		guid_p = &efi_global_variable_guid;
+	else
+		guid_p = (const efi_guid_t *)guid.b;
 
 	/* enumerate and show all UEFI variables */
-	return efi_dump_var_all();
+	return efi_dump_var_all(argc, argv, guid_p, verbose);
 }
 
 /**
@@ -339,18 +453,22 @@ out:
  * Return:	CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
  *
  * This function is for "env set -e" or "setenv -e" command:
- *   => env set -e var [value ...]]
+ *   => env set -e [-guid guid][-nv][-bs][-rt][-a][-v]
+ *		   [-i address,size] var, or
+ *                 var [value ...]
  * Encode values specified and set given UEFI variable.
  * If no value is specified, delete the variable.
  */
 int do_env_set_efi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
-	char *var_name, *value = NULL;
-	efi_uintn_t size = 0;
-	u16 *var_name16 = NULL, *p;
-	size_t len;
+	char *var_name, *value, *ep;
+	ulong addr;
+	efi_uintn_t size;
 	efi_guid_t guid;
 	u32 attributes;
+	bool default_guid, verbose, value_on_memory;
+	u16 *var_name16 = NULL, *p;
+	size_t len;
 	efi_status_t ret;
 
 	if (argc == 1)
@@ -364,32 +482,88 @@ int do_env_set_efi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 		return CMD_RET_FAILURE;
 	}
 
-	attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS |
-		     EFI_VARIABLE_RUNTIME_ACCESS;
-	if (!strcmp(argv[1], "-nv")) {
-		attributes |= EFI_VARIABLE_NON_VOLATILE;
-		argc--;
-		argv++;
-		if (argc == 1)
-			return CMD_RET_SUCCESS;
+	/*
+	 * attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS |
+	 *	     EFI_VARIABLE_RUNTIME_ACCESS;
+	 */
+	value = NULL;
+	size = 0;
+	attributes = 0;
+	guid = efi_global_variable_guid;
+	default_guid = true;
+	verbose = false;
+	value_on_memory = false;
+	for (argc--, argv++; argc > 0 && argv[0][0] == '-'; argc--, argv++) {
+		if (!strcmp(argv[0], "-guid")) {
+			if (argc == 1)
+				return CMD_RET_USAGE;
+
+			argc--;
+			argv++;
+			if (uuid_str_to_bin(argv[0], guid.b,
+					    UUID_STR_FORMAT_GUID)) {
+				printf("## Guid not specified or in XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX format\n");
+				return CMD_RET_FAILURE;
+			}
+			default_guid = false;
+		} else if (!strcmp(argv[0], "-bs")) {
+			attributes |= EFI_VARIABLE_BOOTSERVICE_ACCESS;
+		} else if (!strcmp(argv[0], "-rt")) {
+			attributes |= EFI_VARIABLE_RUNTIME_ACCESS;
+		} else if (!strcmp(argv[0], "-nv")) {
+			attributes |= EFI_VARIABLE_NON_VOLATILE;
+		} else if (!strcmp(argv[0], "-a")) {
+			attributes |= EFI_VARIABLE_APPEND_WRITE;
+		} else if (!strcmp(argv[0], "-i")) {
+			/* data comes from memory */
+			if (argc == 1)
+				return CMD_RET_USAGE;
+
+			argc--;
+			argv++;
+			addr = simple_strtoul(argv[0], &ep, 16);
+			if (*ep != ',')
+				return CMD_RET_USAGE;
+
+			size = simple_strtoul(++ep, NULL, 16);
+			if (!size)
+				return CMD_RET_FAILURE;
+			value_on_memory = true;
+		} else if (!strcmp(argv[0], "-v")) {
+			verbose = true;
+		} else {
+			return CMD_RET_USAGE;
+		}
 	}
+	if (!argc)
+		return CMD_RET_USAGE;
 
-	var_name = argv[1];
-	if (argc == 2) {
-		/* delete */
-		value = NULL;
-		size = 0;
-	} else { /* set */
-		argc -= 2;
-		argv += 2;
+	var_name = argv[0];
+	if (default_guid)
+		guid = efi_global_variable_guid;
+
+	if (verbose) {
+		printf("GUID: %s\n", efi_guid_to_str((const efi_guid_t *)
+						     &guid));
+		printf("Attributes: 0x%x\n", attributes);
+	}
 
-		for ( ; argc > 0; argc--, argv++)
+	/* for value */
+	if (value_on_memory)
+		value = map_sysmem(addr, 0);
+	else if (argc > 1)
+		for (argc--, argv++; argc > 0; argc--, argv++)
 			if (append_value(&value, &size, argv[0]) < 0) {
 				printf("## Failed to process an argument, %s\n",
 				       argv[0]);
 				ret = CMD_RET_FAILURE;
 				goto out;
 			}
+
+	if (size && verbose) {
+		printf("Value:\n");
+		print_hex_dump("    ", DUMP_PREFIX_OFFSET,
+			       16, 1, value, size, true);
 	}
 
 	len = utf8_utf16_strnlen(var_name, strlen(var_name));
@@ -402,17 +576,42 @@ int do_env_set_efi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	p = var_name16;
 	utf8_utf16_strncpy(&p, var_name, len + 1);
 
-	guid = efi_global_variable_guid;
 	ret = EFI_CALL(efi_set_variable(var_name16, &guid, attributes,
 					size, value));
+	unmap_sysmem(value);
 	if (ret == EFI_SUCCESS) {
 		ret = CMD_RET_SUCCESS;
 	} else {
-		printf("## Failed to set EFI variable\n");
+		const char *msg;
+
+		switch (ret) {
+		case EFI_NOT_FOUND:
+			msg = " (not found)";
+			break;
+		case EFI_WRITE_PROTECTED:
+			msg = " (read only)";
+			break;
+		case EFI_INVALID_PARAMETER:
+			msg = " (invalid parameter)";
+			break;
+		case EFI_SECURITY_VIOLATION:
+			msg = " (validation failed)";
+			break;
+		case EFI_OUT_OF_RESOURCES:
+			msg = " (out of memory)";
+			break;
+		default:
+			msg = "";
+			break;
+		}
+		printf("## Failed to set EFI variable%s\n", msg);
 		ret = CMD_RET_FAILURE;
 	}
 out:
-	free(value);
+	if (value_on_memory)
+		unmap_sysmem(value);
+	else
+		free(value);
 	free(var_name16);
 
 	return ret;
-- 
2.21.0

[U-Boot] [PATCH v6 1/1] cmd: env: extend "env [set|print] -e" to manage UEFI variables

[Heinrich Schuchardt]

On 10/24/19 8:17 AM, AKASHI Takahiro wrote:
> With this patch, when setting UEFI variable with "env set -e" command,
> we will be able to
> - specify vendor guid with "-guid guid",
> - specify variable attributes,  BOOTSERVICE_ACCESS, RUNTIME_ACCESS,
>   respectively with "-bs" and "-rt",
> - append a value instead of overwriting with "-a",
> - use memory as variable's value instead of explicit values given
>   at the command line with "-i address,size"
>
> If guid is not explicitly given, default value will be used.
>
> Meanwhile, "env print -e," will be modified so that it will NOT dump
> a variable's value if '-n' is specified.
>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>

Looks fine to me. The only strange behavior is:

=> printenv -e
OsIndicationsSupported:
    EFI_GLOBAL_VARIABLE_GUID: BS|RT, DataSize = 0x8
    00000000: 00 00 00 00 00 00 00 00                          ........
PlatformLang:
    EFI_GLOBAL_VARIABLE_GUID: NV|BS|RT, DataSize = 0x6
    00000000: 65 6e 2d 55 53 00                                en-US.
PlatformLangCodes:
    EFI_GLOBAL_VARIABLE_GUID: BS|RT, DataSize = 0x6
    00000000: 65 6e 2d 55 53 00                                en-US.
RuntimeServicesSupported:
    EFI_GLOBAL_VARIABLE_GUID: BS|RT, DataSize = 0x2
    00000000: 80 05                                            ..
=> env set -e -guid 00000001-0002-0003-0004-010203040506 a b
EFI: Entry efi_set_variable("a" 00000001-0002-0003-0004-010203040506 0 1
000000007eef7610)
EFI: Exit: efi_set_variable: 14
## Failed to set EFI variable (not found)

I would have expected
## Failed to set EFI variable (invalid parameter)

The UEFI spec has:
If a preexisting variable is rewritten with no access attributes
specified, the variable will be deleted.

But "a" is not a preexisting variable. Instead the attributes are invalid.

But as this is a bug in a code that you did not touch:

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

[U-Boot] [PATCH v6 1/1] cmd: env: extend "env [set|print] -e" to manage UEFI variables

[AKASHI Takahiro]

On Fri, Oct 25, 2019 at 08:17:03PM +0200, Heinrich Schuchardt wrote:
> On 10/24/19 8:17 AM, AKASHI Takahiro wrote:
> > With this patch, when setting UEFI variable with "env set -e" command,
> > we will be able to
> > - specify vendor guid with "-guid guid",
> > - specify variable attributes,  BOOTSERVICE_ACCESS, RUNTIME_ACCESS,
> >   respectively with "-bs" and "-rt",
> > - append a value instead of overwriting with "-a",
> > - use memory as variable's value instead of explicit values given
> >   at the command line with "-i address,size"
> >
> > If guid is not explicitly given, default value will be used.
> >
> > Meanwhile, "env print -e," will be modified so that it will NOT dump
> > a variable's value if '-n' is specified.
> >
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> 
> Looks fine to me. The only strange behavior is:
> 
> => printenv -e
> OsIndicationsSupported:
>     EFI_GLOBAL_VARIABLE_GUID: BS|RT, DataSize = 0x8
>     00000000: 00 00 00 00 00 00 00 00                          ........
> PlatformLang:
>     EFI_GLOBAL_VARIABLE_GUID: NV|BS|RT, DataSize = 0x6
>     00000000: 65 6e 2d 55 53 00                                en-US.
> PlatformLangCodes:
>     EFI_GLOBAL_VARIABLE_GUID: BS|RT, DataSize = 0x6
>     00000000: 65 6e 2d 55 53 00                                en-US.
> RuntimeServicesSupported:
>     EFI_GLOBAL_VARIABLE_GUID: BS|RT, DataSize = 0x2
>     00000000: 80 05                                            ..
> => env set -e -guid 00000001-0002-0003-0004-010203040506 a b
> EFI: Entry efi_set_variable("a" 00000001-0002-0003-0004-010203040506 0 1
> 000000007eef7610)
> EFI: Exit: efi_set_variable: 14
> ## Failed to set EFI variable (not found)
> 
> I would have expected
> ## Failed to set EFI variable (invalid parameter)
> 
> The UEFI spec has:
> If a preexisting variable is rewritten with no access attributes
> specified, the variable will be deleted.
> 
> But "a" is not a preexisting variable. Instead the attributes are invalid.

This might justify all arbitrary attribute/option checks being removed
at command level, at least for test purpose.

Thank you for your review.
-Takahiro Akashi


> But as this is a bug in a code that you did not touch:
> 
> Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>