Grabbed from Debian since upstream patch does not apply to 2.2.7.
https://sources.debian.org/patches/expat/2.2.7-2/CVE-2019-15903_Deny_internal_entities_closing_the_doctype.patch/
https://github.com/libexpat/libexpat/commit/c20b758c332d9a13afbbb276d30db1d183a85d43
From c20b758c332d9a13afbbb276d30db1d183a85d43 Mon Sep 17 00:00:00 2001
From: Sebastian Pipping <sebastian@pipping.org>
Date: Wed, 28 Aug 2019 00:24:59 +0200
Subject: [PATCH 1/3] xmlparse.c: Deny internal entities closing the doctype
diff --git a/lib/xmlparse.c b/lib/xmlparse.c
index 0553e3df..c29a6449 100644
--- a/lib/xmlparse.c
+++ b/lib/xmlparse.c
@@ -405,7 +405,7 @@ initializeEncoding(XML_Parser parser);
static enum XML_Error
doProlog(XML_Parser parser, const ENCODING *enc, const char *s,
const char *end, int tok, const char *next, const char **nextPtr,
- XML_Bool haveMore);
+ XML_Bool haveMore, XML_Bool allowClosingDoctype);
static enum XML_Error
processInternalEntity(XML_Parser parser, ENTITY *entity,
XML_Bool betweenDecl);
@@ -4232,7 +4232,7 @@ externalParEntProcessor(XML_Parser parse
parser->m_processor = prologProcessor;
return doProlog(parser, parser->m_encoding, s, end, tok, next,
- nextPtr, (XML_Bool)!parser->m_parsingStatus.finalBuffer);
+ nextPtr, (XML_Bool)!parser->m_parsingStatus.finalBuffer, XML_TRUE);
}
static enum XML_Error PTRCALL
@@ -4282,7 +4282,7 @@ prologProcessor(XML_Parser parser,
const char *next = s;
int tok = XmlPrologTok(parser->m_encoding, s, end, &next);
return doProlog(parser, parser->m_encoding, s, end, tok, next,
- nextPtr, (XML_Bool)!parser->m_parsingStatus.finalBuffer);
+ nextPtr, (XML_Bool)!parser->m_parsingStatus.finalBuffer, XML_TRUE);
}
static enum XML_Error
@@ -4293,7 +4293,8 @@ doProlog(XML_Parser parser,
int tok,
const char *next,
const char **nextPtr,
- XML_Bool haveMore)
+ XML_Bool haveMore,
+ XML_Bool allowClosingDoctype)
{
#ifdef XML_DTD
static const XML_Char externalSubsetName[] = { ASCII_HASH , '\0' };
@@ -4472,6 +4473,11 @@ doProlog(XML_Parser parser,
}
break;
case XML_ROLE_DOCTYPE_CLOSE:
+ if (allowClosingDoctype != XML_TRUE) {
+ /* Must not close doctype from within expanded parameter entities */
+ return XML_ERROR_INVALID_TOKEN;
+ }
+
if (parser->m_doctypeName) {
parser->m_startDoctypeDeclHandler(parser->m_handlerArg, parser->m_doctypeName,
parser->m_doctypeSysid, parser->m_doctypePubid, 0);
@@ -5409,7 +5415,7 @@ processInternalEntity(XML_Parser parser,
if (entity->is_param) {
int tok = XmlPrologTok(parser->m_internalEncoding, textStart, textEnd, &next);
result = doProlog(parser, parser->m_internalEncoding, textStart, textEnd, tok,
- next, &next, XML_FALSE);
+ next, &next, XML_FALSE, XML_FALSE);
}
else
#endif /* XML_DTD */
@@ -5456,7 +5462,7 @@ internalEntityProcessor(XML_Parser parse
if (entity->is_param) {
int tok = XmlPrologTok(parser->m_internalEncoding, textStart, textEnd, &next);
result = doProlog(parser, parser->m_internalEncoding, textStart, textEnd, tok,
- next, &next, XML_FALSE);
+ next, &next, XML_FALSE, XML_TRUE);
}
else
#endif /* XML_DTD */
@@ -5483,7 +5489,7 @@ internalEntityProcessor(XML_Parser parse
parser->m_processor = prologProcessor;
tok = XmlPrologTok(parser->m_encoding, s, end, &next);
return doProlog(parser, parser->m_encoding, s, end, tok, next, nextPtr,
- (XML_Bool)!parser->m_parsingStatus.finalBuffer);
+ (XML_Bool)!parser->m_parsingStatus.finalBuffer, XML_TRUE);
}
else
#endif /* XML_DTD */
From 438493691f1b8620a71d5aee658fe160103ff863 Mon Sep 17 00:00:00 2001
From: Sebastian Pipping <sebastian@pipping.org>
Date: Wed, 28 Aug 2019 15:14:19 +0200
Subject: [PATCH 3/3] tests: Cover denying internal entities closing the
doctype
diff --git a/tests/runtests.c b/tests/runtests.c
index b0d1b0af..e102a55e 100644
--- a/tests/runtests.c
+++ b/tests/runtests.c
@@ -8151,6 +8151,68 @@ START_TEST(test_misc_utf16le)
}
END_TEST
+#ifdef XML_DTD
+START_TEST(test_misc_deny_internal_entity_closing_doctype_issue_317) {
+ const char *const inputOne = "<!DOCTYPE d [\n"
+ "<!ENTITY % e ']><d/>'>\n"
+ "\n"
+ "%e;";
+ const char *const inputTwo = "<!DOCTYPE d [\n"
+ "<!ENTITY % e1 ']><d/>'><!ENTITY % e2 '&e1;'>\n"
+ "\n"
+ "%e2;";
+ const char *const inputThree = "<!DOCTYPE d [\n"
+ "<!ENTITY % e ']><d'>\n"
+ "\n"
+ "%e;";
+ const char *const inputIssue317 = "<!DOCTYPE doc [\n"
+ "<!ENTITY % foo ']>\n"
+ "<doc>Hell<oc (#PCDATA)*>'>\n"
+ "%foo;\n"
+ "]>\n"
+ "<doc>Hello, world</dVc>";
+
+ const char *const inputs[] = {inputOne, inputTwo, inputThree, inputIssue317};
+ size_t inputIndex = 0;
+
+ for (; inputIndex < sizeof(inputs) / sizeof(inputs[0]); inputIndex++) {
+ XML_Parser parser;
+ enum XML_Status parseResult;
+ int setParamEntityResult;
+ XML_Size lineNumber;
+ XML_Size columnNumber;
+ const char *const input = inputs[inputIndex];
+
+ parser = XML_ParserCreate(NULL);
+ setParamEntityResult
+ = XML_SetParamEntityParsing(parser, XML_PARAM_ENTITY_PARSING_ALWAYS);
+ if (setParamEntityResult != 1)
+ fail("Failed to set XML_PARAM_ENTITY_PARSING_ALWAYS.");
+
+ parseResult = XML_Parse(parser, input, (int)strlen(input), 0);
+ if (parseResult != XML_STATUS_ERROR) {
+ parseResult = XML_Parse(parser, "", 0, 1);
+ if (parseResult != XML_STATUS_ERROR) {
+ fail("Parsing was expected to fail but succeeded.");
+ }
+ }
+
+ if (XML_GetErrorCode(parser) != XML_ERROR_INVALID_TOKEN)
+ fail("Error code does not match XML_ERROR_INVALID_TOKEN");
+
+ lineNumber = XML_GetCurrentLineNumber(parser);
+ if (lineNumber != 4)
+ fail("XML_GetCurrentLineNumber does not work as expected.");
+
+ columnNumber = XML_GetCurrentColumnNumber(parser);
+ if (columnNumber != 0)
+ fail("XML_GetCurrentColumnNumber does not work as expected.");
+
+ XML_ParserFree(parser);
+ }
+}
+END_TEST
+#endif
static void
alloc_setup(void)
@@ -12251,6 +12313,10 @@ make_suite(void)
tcase_add_test(tc_misc, test_misc_features);
tcase_add_test(tc_misc, test_misc_attribute_leak);
tcase_add_test(tc_misc, test_misc_utf16le);
+#ifdef XML_DTD
+ tcase_add_test(tc_misc,
+ test_misc_deny_internal_entity_closing_doctype_issue_317);
+#endif
suite_add_tcase(s, tc_alloc);
tcase_add_checked_fixture(tc_alloc, alloc_setup, alloc_teardown);
