From: Lauri Kenttä <lauri.kentta@gmail.com>
Date: Wed, 25 May 2016 18:15:52 +0000 (+0300)
Subject: base64_decode: remove redundant check
X-Git-Tag: php-7.1.0alpha3~1^2^2~5
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=fbc74bb5f9df22a038a00f1f0e2437f1def81b93;p=php

base64_decode: remove redundant check

If length == 0 || *current != '=' is false, the for loop will always
end up in this same point, until the if statement becomes true.
Thus, the if statement is not needed.
---

diff --git a/ext/standard/base64.c b/ext/standard/base64.c
index 352e7ea52c..e8d7f04aa4 100644
--- a/ext/standard/base64.c
+++ b/ext/standard/base64.c
@@ -145,12 +145,13 @@ PHPAPI zend_string *php_base64_decode_ex(const unsigned char *str, size_t length
 	/* run through the whole string, converting as we go */
 	while (length-- > 0 && (ch = *current++) != '\0') {
 		if (ch == base64_pad) {
+			/* fail if the padding character is second in a group (like V===) */
+			/* FIXME: why do we still allow invalid padding in other places in the middle of the string? */
 			if (i % 4 == 1) {
-				if (length == 0 || *current != '=') {
-					zend_string_free(result);
-					return NULL;
-				}
-			} else if (length > 0 && *current != '=' && strict) {
+				zend_string_free(result);
+				return NULL;
+			}
+			if (length > 0 && *current != '=' && strict) {
 				while (--length > 0 && isspace(*++current)) {
 					continue;
 				}