Ensure dissector data parameter is used instead of pinfo->private_data when passing data between dissectors using the "media_type" subdissector.

Change-Id: I82cbfed770b41404bc42cb6a4413db07d04dffdc
Reviewed-on: https://code.wireshark.org/review/5462
Reviewed-by: Michael Mann <mmann78@netscape.net>
Petri-Dish: Michael Mann <mmann78@netscape.net>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Anders Broman <a.broman58@gmail.com>

8 files changed, 23 insertions, 72 deletions

diff --git a/epan/dissectors/packet-http.c b/epan/dissectors/packet-http.c
index 64c27e8a07..b535d9cb8c 100644
--- a/epan/dissectors/packet-http.c
+++ b/epan/dissectors/packet-http.c
@@ -1267,8 +1267,6 @@ dissect_http_message(tvbuff_t *tvb, int offset, packet_info *pinfo,
 		 * There's stuff left over; process it.
 		 */
 		tvbuff_t *next_tvb;
-		void *save_private_data = NULL;
-		gboolean private_data_changed = FALSE;
 		gint chunks_decoded = 0;
 		char *media_str = NULL;
 
@@ -1434,15 +1432,9 @@ dissect_http_message(tvbuff_t *tvb, int offset, packet_info *pinfo,
 			 * Content-Type value.  Is there any subdissector
 			 * for that content type?
 			 */
-			save_private_data = pinfo->private_data;
-			private_data_changed = TRUE;
+			if (headers.content_type_parameters)
+				media_str = wmem_strdup(wmem_packet_scope(), headers.content_type_parameters);
 
-			if (headers.content_type_parameters) {
-				pinfo->private_data = wmem_strdup(wmem_packet_scope(), headers.content_type_parameters);
-				media_str = (char*)pinfo->private_data;
-			}
-			else
-				pinfo->private_data = NULL;
 			/*
 			 * Calling the string handle for the media type
 			 * dissector table will set pinfo->match_string
@@ -1477,7 +1469,7 @@ dissect_http_message(tvbuff_t *tvb, int offset, packet_info *pinfo,
 			/*
 			 * We have a subdissector - call it.
 			 */
-			dissected = call_dissector_only(handle, next_tvb, pinfo, tree, NULL);
+			dissected = call_dissector_only(handle, next_tvb, pinfo, tree, media_str);
 			if (!dissected)
 				expert_add_info(pinfo, http_tree, &ei_http_subdissector_failed);
 		}
@@ -1514,12 +1506,6 @@ dissect_http_message(tvbuff_t *tvb, int offset, packet_info *pinfo,
 
 	body_dissected:
 		/*
-		 * Do *not* attempt at freeing the private data;
-		 * it may be in use by subdissectors.
-		 */
-		if (private_data_changed) /*restore even NULL value*/
-			pinfo->private_data = save_private_data;
-		/*
 		 * We've processed "datalen" bytes worth of data
 		 * (which may be no data at all); advance the
 		 * offset past whatever data we've processed.
diff --git a/epan/dissectors/packet-imf.c b/epan/dissectors/packet-imf.c
index 2747c086c7..b8c044101d 100644
--- a/epan/dissectors/packet-imf.c
+++ b/epan/dissectors/packet-imf.c
@@ -806,15 +806,9 @@ dissect_imf(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
   /* now dissect the MIME based upon the content type */
 
   if(content_type_str && media_type_dissector_table) {
-    void* pd_save;
-    pd_save = pinfo->private_data;
-    pinfo->private_data = parameters;
-
     next_tvb = tvb_new_subset_remaining(tvb, end_offset);
 
-    dissector_try_string(media_type_dissector_table, content_type_str, next_tvb, pinfo, tree, NULL);
-
-    pinfo->private_data = pd_save;
+    dissector_try_string(media_type_dissector_table, content_type_str, next_tvb, pinfo, tree, parameters);
   } else {
 
     /* just show the lines or highlight the rest of the buffer as message text */
diff --git a/epan/dissectors/packet-isup.c b/epan/dissectors/packet-isup.c
index a12b1cb06d..8a651dc92e 100644
--- a/epan/dissectors/packet-isup.c
+++ b/epan/dissectors/packet-isup.c
@@ -10684,7 +10684,7 @@ dissect_bicc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 }
 
 static int
-dissect_application_isup(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+dissect_application_isup(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data)
 {
 /* Set up structures needed to add the protocol subtree and manage it */
   proto_item *ti;
@@ -10694,8 +10694,8 @@ dissect_application_isup(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, vo
   gchar      *content_type_parameter_str;
   guint8      itu_isup_variant = ISUP_ITU_STANDARD_VARIANT; /* Default */
 
-  if (pinfo->private_data) {
-    content_type_parameter_str = ascii_strdown_inplace((gchar *)pinfo->private_data);
+  if (data) {
+    content_type_parameter_str = ascii_strdown_inplace((gchar *)data);
     if (strstr(content_type_parameter_str, "ansi")) {
       isup_standard = ANSI_STANDARD;
       col_append_str(pinfo->cinfo, COL_PROTOCOL, "/ISUP(ANSI)");
diff --git a/epan/dissectors/packet-jxta.c b/epan/dissectors/packet-jxta.c
index d73d796f03..2e4ec17010 100644
--- a/epan/dissectors/packet-jxta.c
+++ b/epan/dissectors/packet-jxta.c
@@ -2049,16 +2049,12 @@ static int dissect_media( const gchar* fullmediatype, tvbuff_t * tvb, packet_inf
         gchar *mediatype = wmem_strdup(wmem_packet_scope(), fullmediatype);
         gchar *parms_at = strchr(mediatype, ';');
         const char *save_match_string = pinfo->match_string;
-        void * save_private_data = pinfo->private_data;
         char *media_str = NULL;
 
         /* Based upon what is done in packet-media.c we set up type and params */
         if (NULL != parms_at) {
-            pinfo->private_data = wmem_strdup( wmem_packet_scope(), parms_at + 1 );
-            media_str = (char*)pinfo->private_data;
+            media_str = wmem_strdup( wmem_packet_scope(), parms_at + 1 );
             *parms_at = '\0';
-        } else {
-            pinfo->private_data = NULL;
         }
 
         /* Set the version that goes to packet-media.c before converting case */
@@ -2088,7 +2084,7 @@ static int dissect_media( const gchar* fullmediatype, tvbuff_t * tvb, packet_inf
                 }
             }
         } else {
-            dissected = dissector_try_string(media_type_dissector_table, mediatype, tvb, pinfo, tree, NULL) ? tvb_length(tvb) : 0;
+            dissected = dissector_try_string(media_type_dissector_table, mediatype, tvb, pinfo, tree, media_str) ? tvb_length(tvb) : 0;
 
             if( dissected != (int) tvb_length(tvb) ) {
                 /* g_message( "%s : %d expected, %d dissected", mediatype, tvb_length(tvb), dissected ); */
@@ -2100,12 +2096,11 @@ static int dissect_media( const gchar* fullmediatype, tvbuff_t * tvb, packet_inf
         }
 
         pinfo->match_string = save_match_string;
-        pinfo->private_data = save_private_data;
     }
 
     if(0 == dissected) {
         /* display it as raw data */
-        dissected = call_dissector_only(data_handle, tvb, pinfo, tree, NULL);
+        dissected = call_dissector(data_handle, tvb, pinfo, tree);
     }
 
     return dissected;
diff --git a/epan/dissectors/packet-msrp.c b/epan/dissectors/packet-msrp.c
index 368c5e5fb0..35ba5152c4 100644
--- a/epan/dissectors/packet-msrp.c
+++ b/epan/dissectors/packet-msrp.c
@@ -689,13 +689,10 @@ dissect_msrp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_
             /* give the content type parameters to sub dissectors */
 
             if ( media_type_str_lower_case != NULL ) {
-                void *save_private_data = pinfo->private_data;
-                pinfo->private_data = content_type_parameter_str;
                 found_match = dissector_try_string(media_type_dissector_table,
                                                media_type_str_lower_case,
                                                next_tvb, pinfo,
-                                               msrp_data_tree, NULL);
-                pinfo->private_data = save_private_data;
+                                               msrp_data_tree, content_type_parameter_str);
                 /* If no match dump as text */
             }
             if ( found_match != TRUE )
diff --git a/epan/dissectors/packet-multipart.c b/epan/dissectors/packet-multipart.c
index c01722e3c9..2e3afcdeb3 100644
--- a/epan/dissectors/packet-multipart.c
+++ b/epan/dissectors/packet-multipart.c
@@ -395,7 +395,7 @@ static char *find_parameter(char *parameters, const char *key, int *retlen)
  * leading hyphens. (quote from rfc2046)
  */
 static multipart_info_t *
-get_multipart_info(packet_info *pinfo)
+get_multipart_info(packet_info *pinfo, const char *str)
 {
     const char *start;
     int len = 0;
@@ -404,7 +404,7 @@ get_multipart_info(packet_info *pinfo)
     char *parameters;
     gint dummy;
 
-    if ((type == NULL) || (pinfo->private_data == NULL)) {
+    if ((type == NULL) || (str == NULL)) {
         /*
          * We need both a content type AND parameters
          * for multipart dissection.
@@ -413,7 +413,7 @@ get_multipart_info(packet_info *pinfo)
     }
 
     /* Clean up the parameters */
-    parameters = unfold_and_compact_mime_header((const char *)pinfo->private_data, &dummy);
+    parameters = unfold_and_compact_mime_header(str, &dummy);
 
     start = find_parameter(parameters, "boundary=", &len);
 
@@ -709,7 +709,6 @@ process_body_part(proto_tree *tree, tvbuff_t *tvb, const guint8 *boundary,
             /*
              * subdissection
              */
-            void *save_private_data = pinfo->private_data;
             gboolean dissected;
 
             /*
@@ -725,18 +724,17 @@ process_body_part(proto_tree *tree, tvbuff_t *tvb, const guint8 *boundary,
 
             }
 
-            pinfo->private_data = parameters;
             /*
              * First try the dedicated multipart dissector table
              */
             dissected = dissector_try_string(multipart_media_subdissector_table,
-                        content_type_str, tmp_tvb, pinfo, subtree, NULL);
+                        content_type_str, tmp_tvb, pinfo, subtree, parameters);
             if (! dissected) {
                 /*
                  * Fall back to the default media dissector table
                  */
                 dissected = dissector_try_string(media_type_dissector_table,
-                        content_type_str, tmp_tvb, pinfo, subtree, NULL);
+                        content_type_str, tmp_tvb, pinfo, subtree, parameters);
             }
             if (! dissected) {
                 const char *save_match_string = pinfo->match_string;
@@ -744,7 +742,6 @@ process_body_part(proto_tree *tree, tvbuff_t *tvb, const guint8 *boundary,
                 call_dissector_with_data(media_handle, tmp_tvb, pinfo, subtree, parameters);
                 pinfo->match_string = save_match_string;
             }
-            pinfo->private_data = save_private_data;
             parameters = NULL; /* Shares same memory as content_type_str */
         } else {
             call_dissector(data_handle, tmp_tvb, pinfo, subtree);
@@ -772,12 +769,12 @@ process_body_part(proto_tree *tree, tvbuff_t *tvb, const guint8 *boundary,
  * Call this method to actually dissect the multipart body.
  * NOTE - Only do so if a boundary string has been found!
  */
-static int dissect_multipart(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+static int dissect_multipart(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data)
 {
     proto_tree *subtree;
     proto_item *ti;
     proto_item *type_ti;
-    multipart_info_t *m_info = get_multipart_info(pinfo);
+    multipart_info_t *m_info = get_multipart_info(pinfo, (const char*)data);
     gint header_start = 0;
     guint8 *boundary;
     gint boundary_len;
diff --git a/epan/dissectors/packet-sip.c b/epan/dissectors/packet-sip.c
index d559c4f1a4..8e26934266 100644
--- a/epan/dissectors/packet-sip.c
+++ b/epan/dissectors/packet-sip.c
@@ -3727,9 +3727,6 @@ dissect_sip_common(tvbuff_t *tvb, int offset, int remaining_length, packet_info
 
         /* give the content type parameters to sub dissectors */
         if ( media_type_str_lower_case != NULL ) {
-            void *save_private_data = pinfo->private_data;
-            pinfo->private_data = content_type_parameter_str;
-
             /* SDP needs a transport layer to determine request/response */
             if (!strcmp(media_type_str_lower_case, "application/sdp")) {
                 /* Resends don't count */
@@ -3777,7 +3774,7 @@ dissect_sip_common(tvbuff_t *tvb, int offset, int remaining_length, packet_info
             found_match = dissector_try_string(media_type_dissector_table,
                                                media_type_str_lower_case,
                                                next_tvb, pinfo,
-                                               message_body_tree, NULL);
+                                               message_body_tree, content_type_parameter_str);
             DENDENT();
             DPRINT(("done calling dissector_try_string() with found_match=%s",
                     found_match?"TRUE":"FALSE"));
@@ -3790,12 +3787,11 @@ dissect_sip_common(tvbuff_t *tvb, int offset, int remaining_length, packet_info
                 found_match = dissector_try_string(media_type_dissector_table,
                                                    "multipart/",
                                                    next_tvb, pinfo,
-                                                   message_body_tree, NULL);
+                                                   message_body_tree, content_type_parameter_str);
                 DENDENT();
                 DPRINT(("done calling dissector_try_string() with found_match=%s",
                         found_match?"TRUE":"FALSE"));
             }
-            pinfo->private_data = save_private_data;
             /* If no match dump as text */
         }
         if ( found_match != TRUE )
diff --git a/epan/dissectors/packet-spdy.c b/epan/dissectors/packet-spdy.c
index b6987f0f58..d2aee32869 100644
--- a/epan/dissectors/packet-spdy.c
+++ b/epan/dissectors/packet-spdy.c
@@ -746,9 +746,7 @@ static int dissect_spdy_data_payload(tvbuff_t *tvb,
     tvbuff_t *next_tvb = NULL;
     tvbuff_t    *data_tvb = NULL;
     spdy_stream_info_t *si = NULL;
-    void *save_private_data = NULL;
     guint8 *copied_data;
-    gboolean private_data_changed = FALSE;
     gboolean is_single_chunk = FALSE;
     gboolean have_entire_body;
     char *media_str = NULL;
@@ -904,14 +902,8 @@ static int dissect_spdy_data_payload(tvbuff_t *tvb,
        * Content-Type value.  Is there any subdissector
        * for that content type?
        */
-      save_private_data = pinfo->private_data;
-      private_data_changed = TRUE;
-
       if (si->content_type_parameters) {
-        pinfo->private_data = wmem_strdup(wmem_packet_scope(), si->content_type_parameters);
-        media_str = (char*)pinfo->private_data;
-      } else {
-        pinfo->private_data = NULL;
+        media_str = wmem_strdup(wmem_packet_scope(), si->content_type_parameters);
       }
       /*
        * Calling the string handle for the media type
@@ -926,7 +918,7 @@ static int dissect_spdy_data_payload(tvbuff_t *tvb,
       /*
        * We have a subdissector - call it.
        */
-      dissected = call_dissector(handle, data_tvb, pinfo, spdy_tree);
+      dissected = call_dissector_with_data(handle, data_tvb, pinfo, spdy_tree, media_str);
     } else {
       dissected = FALSE;
     }
@@ -944,17 +936,11 @@ static int dissect_spdy_data_payload(tvbuff_t *tvb,
 
 body_dissected:
     /*
-     * Do *not* attempt at freeing the private data;
-     * it may be in use by subdissectors.
-     */
-    if (private_data_changed) { /*restore even NULL value*/
-      pinfo->private_data = save_private_data;
-    }
-    /*
      * We've processed frame->length bytes worth of data
      * (which may be no data at all); advance the
      * offset past whatever data we've processed.
      */
+    ;
   }
   return frame->length;
 }