commit 9939d60f01ff598134628ea64b9b65d4b84209ce

Author: Tomas Korbar <tkorbar@redhat.com>

Date:   Mon Feb 21 17:09:17 2022 +0100

    CVE-2021-46143

diff --git a/lib/xmlparse.c b/lib/xmlparse.c

index e743f78..1371f61 100644

--- a/lib/xmlparse.c

+++ b/lib/xmlparse.c

@@ -4501,11 +4501,25 @@ doProlog(XML_Parser parser,

     case XML_ROLE_GROUP_OPEN:

       if (prologState.level >= groupSize) {

         if (groupSize) {

+          /* Detect and prevent integer overflow */

+          if (parser->m_groupSize > (unsigned int)(-1) / 2u) {

+            return XML_ERROR_NO_MEMORY;

+          }

+

           char *temp = (char *)REALLOC(groupConnector, groupSize *= 2);

           if (temp == NULL)

             return XML_ERROR_NO_MEMORY;

           groupConnector = temp;

           if (dtd->scaffIndex) {

+            /* Detect and prevent integer overflow.

+             * The preprocessor guard addresses the "always false" warning

+             * from -Wtype-limits on platforms where

+             * sizeof(unsigned int) < sizeof(size_t), e.g. on x86_64. */

+#if UINT_MAX >= SIZE_MAX

+            if (parser->m_groupSize > (size_t)(-1) / sizeof(int)) {

+              return XML_ERROR_NO_MEMORY;

+            }

+#endif

             int *temp = (int *)REALLOC(dtd->scaffIndex,

                           groupSize * sizeof(int));

             if (temp == NULL)