diff options
| -rw-r--r-- | lib/efi_loader/efi_variable.c | 40 |
1 files changed, 16 insertions, 24 deletions
diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c index 64cf981cdc5..90b637215e4 100644 --- a/lib/efi_loader/efi_variable.c +++ b/lib/efi_loader/efi_variable.c @@ -49,7 +49,7 @@ (strlen("efi_xxxxxxxx-xxxx-xxxx-xxxxxxxxxxxxxxxx_") + \ (MAX_VAR_NAME * MAX_UTF8_PER_UTF16)) -static int hex(unsigned char ch) +static int hex(int ch) { if (ch >= 'a' && ch <= 'f') return ch-'a'+10; @@ -60,44 +60,32 @@ static int hex(unsigned char ch) return -1; } -static const char *hex2mem(u8 *mem, const char *hexstr, int count) +static int hex2mem(u8 *mem, const char *hexstr, int size) { - memset(mem, 0, count/2); + int nibble; + int i; - do { - int nibble; - - *mem = 0; - - if (!count || !*hexstr) + for (i = 0; i < size; i++) { + if (*hexstr == '\0') break; nibble = hex(*hexstr); if (nibble < 0) - break; + return -1; *mem = nibble; - count--; hexstr++; - if (!count || !*hexstr) - break; - nibble = hex(*hexstr); if (nibble < 0) - break; + return -1; *mem = (*mem << 4) | nibble; - count--; hexstr++; mem++; + } - } while (1); - - if (*hexstr) - return hexstr; - - return NULL; + return i; } static char *mem2hex(char *hexstr, const u8 *mem, int count) @@ -209,8 +197,12 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name, efi_guid_t *vendor, if ((s = prefix(val, "(blob)"))) { unsigned len = strlen(s); + /* number of hexadecimal digits must be even */ + if (len & 1) + return EFI_EXIT(EFI_DEVICE_ERROR); + /* two characters per byte: */ - len = DIV_ROUND_UP(len, 2); + len /= 2; *data_size = len; if (in_size < len) @@ -219,7 +211,7 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name, efi_guid_t *vendor, if (!data) return EFI_EXIT(EFI_INVALID_PARAMETER); - if (hex2mem(data, s, len * 2)) + if (hex2mem(data, s, len) != len) return EFI_EXIT(EFI_DEVICE_ERROR); debug("%s: got value: \"%s\"\n", __func__, s); |