efi_loader: use short-form DP for load options

The GUID of partitions is sufficient for identification and will stay
constant in the lifetime of a boot option. The preceding path of the
device-path may change due to changes in the enumeration of devices.
Therefore it is preferable to use the short-form of device-paths in load
options. Adjust the 'efidebug boot add' command accordingly.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
This commit is contained in:
Heinrich Schuchardt 2022-02-26 12:10:10 +01:00
parent 9cdf470274
commit 63276a569d

View file

@ -734,20 +734,20 @@ static int do_efi_show_tables(struct cmd_tbl *cmdtp, int flag,
}
/**
* create_initrd_dp() - Create a special device for our Boot### option
*
* @dev: Device
* @part: Disk partition
* @file: Filename
* Return: Pointer to the device path or ERR_PTR
* create_initrd_dp() - create a special device for our Boot### option
*
* @dev: device
* @part: disk partition
* @file: filename
* @shortform: create short form device path
* Return: pointer to the device path or ERR_PTR
*/
static
struct efi_device_path *create_initrd_dp(const char *dev, const char *part,
const char *file)
const char *file, int shortform)
{
struct efi_device_path *tmp_dp = NULL, *tmp_fp = NULL;
struct efi_device_path *tmp_dp = NULL, *tmp_fp = NULL, *short_fp = NULL;
struct efi_device_path *initrd_dp = NULL;
efi_status_t ret;
const struct efi_initrd_dp id_dp = {
@ -771,9 +771,13 @@ struct efi_device_path *create_initrd_dp(const char *dev, const char *part,
printf("Cannot create device path for \"%s %s\"\n", part, file);
goto out;
}
if (shortform)
short_fp = efi_dp_shorten(tmp_fp);
if (!short_fp)
short_fp = tmp_fp;
initrd_dp = efi_dp_append((const struct efi_device_path *)&id_dp,
tmp_fp);
short_fp);
out:
efi_free_pool(tmp_dp);
@ -807,6 +811,7 @@ static int do_efi_boot_add(struct cmd_tbl *cmdtp, int flag,
size_t label_len, label_len16;
u16 *label;
struct efi_device_path *device_path = NULL, *file_path = NULL;
struct efi_device_path *fp_free = NULL;
struct efi_device_path *final_fp = NULL;
struct efi_device_path *initrd_dp = NULL;
struct efi_load_option lo;
@ -826,7 +831,18 @@ static int do_efi_boot_add(struct cmd_tbl *cmdtp, int flag,
argc--;
argv++; /* 'add' */
for (; argc > 0; argc--, argv++) {
if (!strcmp(argv[0], "-b")) {
int shortform;
if (*argv[0] != '-' || strlen(argv[0]) != 2) {
r = CMD_RET_USAGE;
goto out;
}
shortform = 0;
switch (argv[0][1]) {
case 'b':
shortform = 1;
/* fallthrough */
case 'B':
if (argc < 5 || lo.label) {
r = CMD_RET_USAGE;
goto out;
@ -849,24 +865,33 @@ static int do_efi_boot_add(struct cmd_tbl *cmdtp, int flag,
/* file path */
ret = efi_dp_from_name(argv[3], argv[4], argv[5],
&device_path, &file_path);
&device_path, &fp_free);
if (ret != EFI_SUCCESS) {
printf("Cannot create device path for \"%s %s\"\n",
argv[3], argv[4]);
r = CMD_RET_FAILURE;
goto out;
}
if (shortform)
file_path = efi_dp_shorten(fp_free);
if (!file_path)
file_path = fp_free;
fp_size += efi_dp_size(file_path) +
sizeof(struct efi_device_path);
argc -= 5;
argv += 5;
} else if (!strcmp(argv[0], "-i")) {
break;
case 'i':
shortform = 1;
/* fallthrough */
case 'I':
if (argc < 3 || initrd_dp) {
r = CMD_RET_USAGE;
goto out;
}
initrd_dp = create_initrd_dp(argv[1], argv[2], argv[3]);
initrd_dp = create_initrd_dp(argv[1], argv[2], argv[3],
shortform);
if (!initrd_dp) {
printf("Cannot add an initrd\n");
r = CMD_RET_FAILURE;
@ -876,7 +901,8 @@ static int do_efi_boot_add(struct cmd_tbl *cmdtp, int flag,
argv += 3;
fp_size += efi_dp_size(initrd_dp) +
sizeof(struct efi_device_path);
} else if (!strcmp(argv[0], "-s")) {
break;
case 's':
if (argc < 1 || lo.optional_data) {
r = CMD_RET_USAGE;
goto out;
@ -884,7 +910,8 @@ static int do_efi_boot_add(struct cmd_tbl *cmdtp, int flag,
lo.optional_data = (const u8 *)argv[1];
argc -= 1;
argv += 1;
} else {
break;
default:
r = CMD_RET_USAGE;
goto out;
}
@ -927,7 +954,7 @@ out:
efi_free_pool(final_fp);
efi_free_pool(initrd_dp);
efi_free_pool(device_path);
efi_free_pool(file_path);
efi_free_pool(fp_free);
free(lo.label);
return r;
@ -1571,12 +1598,11 @@ static int do_efidebug(struct cmd_tbl *cmdtp, int flag,
static char efidebug_help_text[] =
" - UEFI Shell-like interface to configure UEFI environment\n"
"\n"
"efidebug boot add "
"-b <bootid> <label> <interface> <devnum>[:<part>] <file path> "
"-i <interface> <devnum>[:<part>] <initrd file path> "
"-s '<optional data>'\n"
" - set UEFI BootXXXX variable\n"
" <load options> will be passed to UEFI application\n"
"efidebug boot add - set UEFI BootXXXX variable\n"
" -b|-B <bootid> <label> <interface> <devnum>[:<part>] <file path>\n"
" -i|-I <interface> <devnum>[:<part>] <initrd file path>\n"
" (-b, -i for short form device path)\n"
" -s '<optional data>'\n"
"efidebug boot rm <bootid#1> [<bootid#2> [<bootid#3> [...]]]\n"
" - delete UEFI BootXXXX variables\n"
"efidebug boot dump\n"