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(svn r15626) -Fix [FS#2698]: UTF8 string handling could cause buffer overruns.

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rubidium
2009-03-06 01:23:25 +00:00
parent c3a7e6b693
commit 86ca408d46
8 changed files with 38 additions and 13 deletions
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24
src/string.cpp
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@@ -97,13 +97,27 @@ char *CDECL str_fmt(const char *str, ...)
}
void str_validate(char *str, bool allow_newlines, bool ignore)
void str_validate(char *str, const char *last, bool allow_newlines, bool ignore)
{
char *dst = str;
WChar c;
size_t len;
/* Assume the ABSOLUTE WORST to be in str as it comes from the outside. */
char *dst = str;
while (*str != '\0') {
size_t len = Utf8EncodedCharLen(*str);
/* If the character is unknown, i.e. encoded length is 0
* we assume worst case for the length check.
* The length check is needed to prevent Utf8Decode to read
* over the terminating '\0' if that happens to be placed
* within the encoding of an UTF8 character. */
if ((len == 0 && str + 4 > last) || str + len > last) break;
WChar c;
len = Utf8Decode(&c, str);
/* It's possible to encode the string termination character
* into a multiple bytes. This prevents those termination
* characters to be skipped */
if (c == '\0') break;
for (len = Utf8Decode(&c, str); c != '\0'; len = Utf8Decode(&c, str)) {
if (IsPrintable(c) && (c < SCC_SPRITE_START || c > SCC_SPRITE_END)) {
/* Copy the character back. Even if dst is current the same as str
* (i.e. no characters have been changed) this is quicker than