Avoid memory leak if xmlParserInputBufferCreateIO fails

For https://bugzilla.gnome.org/show_bug.cgi?id=643949

In case of error on an IO creation input the given context
is terminated with the given close function, except if the
error happened in xmlParserInputBufferCreateIO. This can
lead to a resource leak which is fixed by this patch.

3 files changed, 36 insertions, 13 deletions

diff --git a/HTMLparser.c b/HTMLparser.c
index 2eb3fb49..bf15c6a5 100644
--- a/HTMLparser.c
+++ b/HTMLparser.c
@@ -6780,8 +6780,11 @@ htmlReadIO(xmlInputReadCallback ioread, xmlInputCloseCallback ioclose,
 
     input = xmlParserInputBufferCreateIO(ioread, ioclose, ioctx,
                                          XML_CHAR_ENCODING_NONE);
-    if (input == NULL)
+    if (input == NULL) {
+        if (ioclose != NULL)
+            ioclose(ioctx);
         return (NULL);
+    }
     ctxt = htmlNewParserCtxt();
     if (ctxt == NULL) {
         xmlFreeParserInputBuffer(input);
@@ -6980,8 +6983,11 @@ htmlCtxtReadIO(htmlParserCtxtPtr ctxt, xmlInputReadCallback ioread,
 
     input = xmlParserInputBufferCreateIO(ioread, ioclose, ioctx,
                                          XML_CHAR_ENCODING_NONE);
-    if (input == NULL)
+    if (input == NULL) {
+        if (ioclose != NULL)
+            ioclose(ioctx);
         return (NULL);
+    }
     stream = xmlNewIOInputStream(ctxt, input, XML_CHAR_ENCODING_NONE);
     if (stream == NULL) {
         xmlFreeParserInputBuffer(input);
diff --git a/parser.c b/parser.c
index 7ea5a887..b39aa59c 100644
--- a/parser.c
+++ b/parser.c
@@ -11984,11 +11984,15 @@ xmlCreateIOParserCtxt(xmlSAXHandlerPtr sax, void *user_data,
     xmlParserCtxtPtr ctxt;
     xmlParserInputPtr inputStream;
     xmlParserInputBufferPtr buf;
-    
+
     if (ioread == NULL) return(NULL);
 
     buf = xmlParserInputBufferCreateIO(ioread, ioclose, ioctx, enc);
-    if (buf == NULL) return(NULL);
+    if (buf == NULL) {
+        if (ioclose != NULL)
+            ioclose(ioctx);
+        return (NULL);
+    }
 
     ctxt = xmlNewParserCtxt();
     if (ctxt == NULL) {
@@ -12013,7 +12017,7 @@ xmlCreateIOParserCtxt(xmlSAXHandlerPtr sax, void *user_data,
 	    memcpy(ctxt->sax, sax, sizeof(xmlSAXHandlerV1));
 	if (user_data != NULL)
 	    ctxt->userData = user_data;
-    }	
+    }
 
     inputStream = xmlNewIOInputStream(ctxt, buf, enc);
     if (inputStream == NULL) {
@@ -14787,7 +14791,7 @@ xmlReadFd(int fd, const char *URL, const char *encoding, int options)
  * @options:  a combination of xmlParserOption
  *
  * parse an XML document from I/O functions and source and build a tree.
- * 
+ *
  * Returns the resulting document tree
  */
 xmlDocPtr
@@ -14803,8 +14807,11 @@ xmlReadIO(xmlInputReadCallback ioread, xmlInputCloseCallback ioclose,
 
     input = xmlParserInputBufferCreateIO(ioread, ioclose, ioctx,
                                          XML_CHAR_ENCODING_NONE);
-    if (input == NULL)
+    if (input == NULL) {
+        if (ioclose != NULL)
+            ioclose(ioctx);
         return (NULL);
+    }
     ctxt = xmlNewParserCtxt();
     if (ctxt == NULL) {
         xmlFreeParserInputBuffer(input);
@@ -14830,7 +14837,7 @@ xmlReadIO(xmlInputReadCallback ioread, xmlInputCloseCallback ioclose,
  *
  * parse an XML in-memory document and build a tree.
  * This reuses the existing @ctxt parser context
- * 
+ *
  * Returns the resulting document tree
  */
 xmlDocPtr
@@ -14985,7 +14992,7 @@ xmlCtxtReadFd(xmlParserCtxtPtr ctxt, int fd,
  *
  * parse an XML document from I/O functions and source and build a tree.
  * This reuses the existing @ctxt parser context
- * 
+ *
  * Returns the resulting document tree
  */
 xmlDocPtr
@@ -15006,8 +15013,11 @@ xmlCtxtReadIO(xmlParserCtxtPtr ctxt, xmlInputReadCallback ioread,
 
     input = xmlParserInputBufferCreateIO(ioread, ioclose, ioctx,
                                          XML_CHAR_ENCODING_NONE);
-    if (input == NULL)
+    if (input == NULL) {
+        if (ioclose != NULL)
+            ioclose(ioctx);
         return (NULL);
+    }
     stream = xmlNewIOInputStream(ctxt, input, XML_CHAR_ENCODING_NONE);
     if (stream == NULL) {
         xmlFreeParserInputBuffer(input);
diff --git a/xmlreader.c b/xmlreader.c
index 864abf0a..ef41927e 100644
--- a/xmlreader.c
+++ b/xmlreader.c
@@ -5401,8 +5401,11 @@ xmlReaderForIO(xmlInputReadCallback ioread, xmlInputCloseCallback ioclose,
 
     input = xmlParserInputBufferCreateIO(ioread, ioclose, ioctx,
                                          XML_CHAR_ENCODING_NONE);
-    if (input == NULL)
+    if (input == NULL) {
+        if (ioclose != NULL)
+            ioclose(ioctx);
         return (NULL);
+    }
     reader = xmlNewTextReader(input, URL);
     if (reader == NULL) {
         xmlFreeParserInputBuffer(input);
@@ -5619,10 +5622,14 @@ xmlReaderNewIO(xmlTextReaderPtr reader, xmlInputReadCallback ioread,
 
     input = xmlParserInputBufferCreateIO(ioread, ioclose, ioctx,
                                          XML_CHAR_ENCODING_NONE);
-    if (input == NULL)
-        return (-1);
+    if (input == NULL) {
+        if (ioclose != NULL)
+            ioclose(ioctx);
+        return (NULL);
+    }
     return (xmlTextReaderSetup(reader, input, URL, encoding, options));
 }
+
 /************************************************************************
  *									*
  *			Utilities					*