On Fri, Mar 20, 2020 at 07:28:19PM +0100, Heinrich Schuchardt wrote:

The runtime service GetNextVariable() returns the length of the next variable including the closing 0x0000. This length should be in bytes.

Comparing the output of EDK2 and U-Boot shows that this is currently not correctly implemented:

EDK2: OsIndicationsSupported: 46 PlatformLang: 26 PlatformLangCodes: 36

U-Boot: OsIndicationsSupported: 23 PlatformLang: 13 PlatformLangCodes: 18

Provide correct length in GetNextVariable().

Please also correct a function description of GetNextVariable().

-Takahiro Akashi

Fixes: d99a87f84b75 ("efi_loader: implement GetNextVariableName()") Signed-off-by: Heinrich Schuchardt xypron.glpk@gmx.de

---

lib/efi_loader/efi_variable.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c index c316bdfec0..04ead34c6f 100644 --- a/lib/efi_loader/efi_variable.c +++ b/lib/efi_loader/efi_variable.c @@ -299,7 +299,7 @@ static efi_status_t parse_uboot_variable(char *variable, p = variable_name; utf8_utf16_strncpy(&p, name, name_len); variable_name[name_len] = 0;

• *variable_name_size = name_len + 1;

• *variable_name_size = sizeof(u16) * (name_len + 1);

  /* guid */ c = *(name - 1);

-- 2.25.1

On Fri, Mar 20, 2020 at 07:28:20PM +0100, Heinrich Schuchardt wrote:

GetNextVariableName should report the length of the variable including the final 0x0000 in bytes.

Check this in the unit test.

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

lib/efi_selftest/efi_selftest_variables.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/efi_selftest/efi_selftest_variables.c b/lib/efi_selftest/efi_selftest_variables.c index 5d98c029b8..b7ead340f5 100644 --- a/lib/efi_selftest/efi_selftest_variables.c +++ b/lib/efi_selftest/efi_selftest_variables.c @@ -155,8 +155,14 @@ static int execute(void) return EFI_ST_FAILURE; } if (!memcmp(&guid, &guid_vendor0, sizeof(efi_guid_t)) &&

•     !efi_st_strcmp_16_8(varname, "efi_st_var0"))
  

•     !efi_st_strcmp_16_8(varname, "efi_st_var0")) {
  flag |= 1;
  

• 	if (len != 24) {
  

• 		efi_st_error("GetNextVariableName report wrong length %u, expected 24\n",
  

• 			     (unsigned int)len);
  

• 		return EFI_ST_FAILURE;
  

• 	}
  

• }
  

  if (!memcmp(&guid, &guid_vendor1, sizeof(efi_guid_t)) && !efi_st_strcmp_16_8(varname, "efi_st_var1"))

Logically, length check should be added here, too.

-Takahiro Akashi

	flag |= 2;

-- 2.25.1