From 0e69bcfb27644f9e7c575aa3565bcff922c7dec2 Mon Sep 17 00:00:00 2001 From: Heinrich Schuchardt Date: Sun, 31 May 2020 22:46:09 +0200 Subject: efi_loader: validate load option For passing the optional data of the load option to the loaded imaged protocol we need its size. efi_deserialize_load_option() is changed to return the size of the optional data. As a by-product we get a partial validation of the load option. Checking the length of the device path remains to be implemented. Some Coverity defects identified the load options as user input because get_unaligned_le32() and get_unaligned_le16() is called. But non of these Coverity defects can be resolved without marking functions with Coverity specific tags. Reported-by: Coverity (CID 303760) Reported-by: Coverity (CID 303768) Reported-by: Coverity (CID 303776) Signed-off-by: Heinrich Schuchardt --- cmd/efidebug.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) (limited to 'cmd') diff --git a/cmd/efidebug.c b/cmd/efidebug.c index 32430e62f0..58018f700c 100644 --- a/cmd/efidebug.c +++ b/cmd/efidebug.c @@ -694,14 +694,19 @@ static int do_efi_boot_rm(struct cmd_tbl *cmdtp, int flag, * * Decode the value of UEFI load option variable and print information. */ -static void show_efi_boot_opt_data(u16 *varname16, void *data, size_t size) +static void show_efi_boot_opt_data(u16 *varname16, void *data, size_t *size) { struct efi_load_option lo; char *label, *p; size_t label_len16, label_len; u16 *dp_str; + efi_status_t ret; - efi_deserialize_load_option(&lo, data); + ret = efi_deserialize_load_option(&lo, data, size); + if (ret != EFI_SUCCESS) { + printf("%ls: invalid load option\n", varname16); + return; + } label_len16 = u16_strlen(lo.label); label_len = utf16_utf8_strnlen(lo.label, label_len16); @@ -728,8 +733,7 @@ static void show_efi_boot_opt_data(u16 *varname16, void *data, size_t size) printf(" data:\n"); print_hex_dump(" ", DUMP_PREFIX_OFFSET, 16, 1, - lo.optional_data, size + (u8 *)data - - (u8 *)lo.optional_data, true); + lo.optional_data, *size, true); free(label); } @@ -759,7 +763,7 @@ static void show_efi_boot_opt(u16 *varname16) &efi_global_variable_guid, NULL, &size, data)); if (ret == EFI_SUCCESS) - show_efi_boot_opt_data(varname16, data, size); + show_efi_boot_opt_data(varname16, data, &size); free(data); } } @@ -920,7 +924,12 @@ static int show_efi_boot_order(void) goto out; } - efi_deserialize_load_option(&lo, data); + ret = efi_deserialize_load_option(&lo, data, &size); + if (ret != EFI_SUCCESS) { + printf("%ls: invalid load option\n", var_name16); + ret = CMD_RET_FAILURE; + goto out; + } label_len16 = u16_strlen(lo.label); label_len = utf16_utf8_strnlen(lo.label, label_len16); -- cgit v1.2.3