From patchwork Sun Mar 22 09:57:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heinrich Schuchardt X-Patchwork-Id: 244082 List-Id: U-Boot discussion From: xypron.glpk at gmx.de (Heinrich Schuchardt) Date: Sun, 22 Mar 2020 10:57:30 +0100 Subject: [PATCH v2 1/2] efi_loader: correct reported length in GetNextVariable() In-Reply-To: <20200322095731.76982-1-xypron.glpk@gmx.de> References: <20200322095731.76982-1-xypron.glpk@gmx.de> Message-ID: <20200322095731.76982-2-xypron.glpk@gmx.de> 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(). Fixes: d99a87f84b75 ("efi_loader: implement GetNextVariableName()") Signed-off-by: Heinrich Schuchardt --- v2: correct return value of the initial call too --- lib/efi_loader/efi_variable.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) -- 2.25.1 diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c index 99d2f01f57..3bec2d0d17 100644 --- a/lib/efi_loader/efi_variable.c +++ b/lib/efi_loader/efi_variable.c @@ -273,7 +273,8 @@ static efi_status_t parse_uboot_variable(char *variable, u32 *attributes) { char *guid, *name, *end, c; - unsigned long name_len; + size_t name_len; + efi_uintn_t old_variable_name_size; u16 *p; guid = strchr(variable, '_'); @@ -289,17 +290,17 @@ static efi_status_t parse_uboot_variable(char *variable, return EFI_INVALID_PARAMETER; name_len = end - name; - if (*variable_name_size < (name_len + 1)) { - *variable_name_size = name_len + 1; + old_variable_name_size = *variable_name_size; + *variable_name_size = sizeof(u16) * (name_len + 1); + if (old_variable_name_size < *variable_name_size) return EFI_BUFFER_TOO_SMALL; - } + end++; /* point to value */ /* variable name */ p = variable_name; utf8_utf16_strncpy(&p, name, name_len); variable_name[name_len] = 0; - *variable_name_size = name_len + 1; /* guid */ c = *(name - 1);