Fixes RegEx::sub injecting null character (issue 15409)

This commit is contained in:
Bernhard Liebl 2018-01-07 00:59:38 +01:00
parent fab0d53f7e
commit 57e77db0ed

View file

@ -343,15 +343,20 @@ String RegEx::sub(const String &p_subject, const String &p_replacement, bool p_a
ERR_FAIL_COND_V(!is_valid(), String());
String output;
output.resize(p_subject.length());
// safety_zone is the number of chars we allocate in addition to the number of chars expected in order to
// guard against the PCRE API writing one additional \0 at the end. PCRE's API docs are unclear on whether
// PCRE understands outlength in pcre2_substitute() as counting an implicit additional terminating char or
// not. always allocating one char more than telling PCRE has us on the safe side.
const int safety_zone = 1;
PCRE2_SIZE olength = p_subject.length() + 1; // space for output string and one terminating \0 character
Vector<CharType> output;
output.resize(olength + safety_zone);
uint32_t flags = PCRE2_SUBSTITUTE_OVERFLOW_LENGTH;
if (p_all)
flags |= PCRE2_SUBSTITUTE_GLOBAL;
PCRE2_SIZE olength = output.length();
PCRE2_SIZE length = p_subject.length();
if (p_end >= 0 && (uint32_t)p_end < length)
length = p_end;
@ -363,15 +368,15 @@ String RegEx::sub(const String &p_subject, const String &p_replacement, bool p_a
pcre2_match_context_16 *mctx = pcre2_match_context_create_16(gctx);
PCRE2_SPTR16 s = (PCRE2_SPTR16)p_subject.c_str();
PCRE2_SPTR16 r = (PCRE2_SPTR16)p_replacement.c_str();
PCRE2_UCHAR16 *o = (PCRE2_UCHAR16 *)output.c_str();
PCRE2_UCHAR16 *o = (PCRE2_UCHAR16 *)output.ptrw();
pcre2_match_data_16 *match = pcre2_match_data_create_from_pattern_16(c, gctx);
int res = pcre2_substitute_16(c, s, length, p_offset, flags, match, mctx, r, p_replacement.length(), o, &olength);
if (res == PCRE2_ERROR_NOMEMORY) {
output.resize(olength);
o = (PCRE2_UCHAR16 *)output.c_str();
output.resize(olength + safety_zone);
o = (PCRE2_UCHAR16 *)output.ptrw();
res = pcre2_substitute_16(c, s, length, p_offset, flags, match, mctx, r, p_replacement.length(), o, &olength);
}
@ -388,15 +393,15 @@ String RegEx::sub(const String &p_subject, const String &p_replacement, bool p_a
pcre2_match_context_32 *mctx = pcre2_match_context_create_32(gctx);
PCRE2_SPTR32 s = (PCRE2_SPTR32)p_subject.c_str();
PCRE2_SPTR32 r = (PCRE2_SPTR32)p_replacement.c_str();
PCRE2_UCHAR32 *o = (PCRE2_UCHAR32 *)output.c_str();
PCRE2_UCHAR32 *o = (PCRE2_UCHAR32 *)output.ptrw();
pcre2_match_data_32 *match = pcre2_match_data_create_from_pattern_32(c, gctx);
int res = pcre2_substitute_32(c, s, length, p_offset, flags, match, mctx, r, p_replacement.length(), o, &olength);
if (res == PCRE2_ERROR_NOMEMORY) {
output.resize(olength);
o = (PCRE2_UCHAR32 *)output.c_str();
output.resize(olength + safety_zone);
o = (PCRE2_UCHAR32 *)output.ptrw();
res = pcre2_substitute_32(c, s, length, p_offset, flags, match, mctx, r, p_replacement.length(), o, &olength);
}
@ -407,7 +412,7 @@ String RegEx::sub(const String &p_subject, const String &p_replacement, bool p_a
return String();
}
return output;
return String(output.ptr(), olength);
}
bool RegEx::is_valid() const {