efi: Do variable name validation tests in utf8

commit 3dcb1f55dfc7631695e69df4a0d589ce5274bd07 upstream.

Actually translate from ucs2 to utf8 before doing the test, and then
test against our other utf8 data, instead of fudging it.

Signed-off-by: Peter Jones <pjones@redhat.com>
Acked-by: Matthew Garrett <mjg59@coreos.com>
Tested-by: Lee, Chun-Yi <jlee@suse.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c
index 70a0fb10517f94ea5b28bada280d9935f0693cc7..5c5fde3e6c37738a57bebb0caf36d7ef6000a4a5 100644 (file)
--- a/drivers/firmware/efi/vars.c
+++ b/drivers/firmware/efi/vars.c
@@ -189,10 +189,19 @@ static const struct variable_validate variable_validate[] = {
 };
 
 bool
-efivar_validate(efi_char16_t *var_name, u8 *data, unsigned long len)
+efivar_validate(efi_char16_t *var_name, u8 *data, unsigned long data_size)
 {
        int i;
-       u16 *unicode_name = var_name;
+       unsigned long utf8_size;
+       u8 *utf8_name;
+
+       utf8_size = ucs2_utf8size(var_name);
+       utf8_name = kmalloc(utf8_size + 1, GFP_KERNEL);
+       if (!utf8_name)
+               return false;
+
+       ucs2_as_utf8(utf8_name, var_name, utf8_size);
+       utf8_name[utf8_size] = '\0';
 
        for (i = 0; variable_validate[i].validate != NULL; i++) {
                const char *name = variable_validate[i].name;
@@ -200,28 +209,29 @@ efivar_validate(efi_char16_t *var_name, u8 *data, unsigned long len)
 
                for (match = 0; ; match++) {
                        char c = name[match];
-                       u16 u = unicode_name[match];
-
-                       /* All special variables are plain ascii */
-                       if (u > 127)
-                               return true;
+                       char u = utf8_name[match];
 
                        /* Wildcard in the matching name means we've matched */
-                       if (c == '*')
+                       if (c == '*') {
+                               kfree(utf8_name);
                                return variable_validate[i].validate(var_name,
-                                                            match, data, len);
+                                                       match, data, data_size);
+                       }
 
                        /* Case sensitive match */
                        if (c != u)
                                break;
 
                        /* Reached the end of the string while matching */
-                       if (!c)
+                       if (!c) {
+                               kfree(utf8_name);
                                return variable_validate[i].validate(var_name,
-                                                            match, data, len);
+                                                       match, data, data_size);
+                       }
                }
        }
 
+       kfree(utf8_name);
        return true;
 }
 EXPORT_SYMBOL_GPL(efivar_validate);