From ad68ecf1d967f8e60c19c28a2bc23daf15389076 Mon Sep 17 00:00:00 2001 From: Timur Pocheptsov Date: Wed, 18 Mar 2020 19:54:33 +0100 Subject: q_getTimeFromASN1: fix invalid access MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit No sanitizer is needed, just looking at the code is enough. It was wrong. Change-Id: I9df417c137d6b3361c3161865e099a8be40860de Reviewed-by: Lars Knoll Reviewed-by: Mårten Nordheim --- src/network/ssl/qsslsocket_openssl_symbols.cpp | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/src/network/ssl/qsslsocket_openssl_symbols.cpp b/src/network/ssl/qsslsocket_openssl_symbols.cpp index 26336edd3d..85029a6ff3 100644 --- a/src/network/ssl/qsslsocket_openssl_symbols.cpp +++ b/src/network/ssl/qsslsocket_openssl_symbols.cpp @@ -1428,6 +1428,9 @@ QDateTime q_getTimeFromASN1(const ASN1_TIME *aTime) { size_t lTimeLength = aTime->length; char *pString = (char *) aTime->data; + auto isValidPointer = [pString, lTimeLength](const char *const probe){ + return size_t(probe - pString) < lTimeLength; + }; if (aTime->type == V_ASN1_UTCTIME) { @@ -1446,12 +1449,21 @@ QDateTime q_getTimeFromASN1(const ASN1_TIME *aTime) *pBuffer++ = '0'; } else { *pBuffer++ = *pString++; + if (!isValidPointer(pString)) // Nah. + return {}; *pBuffer++ = *pString++; + if (!isValidPointer(pString)) // Nah. + return {}; // Skip any fractional seconds... if (*pString == '.') { pString++; - while ((*pString >= '0') && (*pString <= '9')) + if (!isValidPointer(pString)) // Oh no, cannot dereference (see below). + return {}; + while ((*pString >= '0') && (*pString <= '9')) { pString++; + if (!isValidPointer(pString)) // No and no. + return {}; + } } } @@ -1465,6 +1477,10 @@ QDateTime q_getTimeFromASN1(const ASN1_TIME *aTime) if ((*pString != '+') && (*pString != '-')) return QDateTime(); + if (!isValidPointer(pString + 4)) { + // What kind of input parameters we were provided with? To hell with them! + return {}; + } lSecondsFromUCT = ((pString[1] - '0') * 10 + (pString[2] - '0')) * 60; lSecondsFromUCT += (pString[3] - '0') * 10 + (pString[4] - '0'); lSecondsFromUCT *= 60; -- cgit v1.2.3