Reject the packet if data is NULL without doing anything else.

Note: We *might* want to do _something_ but that _something_ should be well-defined and consistent across all dissectors.  Previously, some dissectors called proto_tree_add_text() to add some error message text to the tree, while others called DISSECTOR_ASSERT().

svn path=/trunk/; revision=53895

17 files changed, 109 insertions, 159 deletions

diff --git a/asn1/disp/packet-disp-template.c b/asn1/disp/packet-disp-template.c
index 9245d3c938..0924ee9657 100644
--- a/asn1/disp/packet-disp-template.c
+++ b/asn1/disp/packet-disp-template.c
@@ -87,18 +87,12 @@ dissect_disp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void* d
 	const char *disp_op_name;
 	asn1_ctx_t asn1_ctx;
 
-	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
-
-	/* do we have operation information from the ROS dissector?  */
-	if( data == NULL ){
-		if(parent_tree){
-			proto_tree_add_text(parent_tree, tvb, offset, -1,
-				"Internal error: can't get operation information from ROS dissector.");
-		}
+	/* do we have operation information from the ROS dissector */
+	if (data == NULL)
 		return 0;
-	}
+	session  = (struct SESSION_DATA_STRUCTURE*)data;
 
-	session  = ((struct SESSION_DATA_STRUCTURE*)data);
+	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
 
 	asn1_ctx.private_data = session;
 
diff --git a/asn1/dop/packet-dop-template.c b/asn1/dop/packet-dop-template.c
index 0276702d10..3ce204710b 100644
--- a/asn1/dop/packet-dop-template.c
+++ b/asn1/dop/packet-dop-template.c
@@ -129,18 +129,12 @@ dissect_dop(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void* da
 	const char *dop_op_name;
 	asn1_ctx_t asn1_ctx;
 
-	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
-
-	/* do we have operation information from the ROS dissector?  */
-	if( data == NULL ){
-		if(parent_tree){
-			proto_tree_add_text(parent_tree, tvb, offset, -1,
-				"Internal error: can't get operation information from ROS dissector.");
-		}
-		return  0;
-	}
+	/* do we have operation information from the ROS dissector? */
+	if (data == NULL)
+		return 0;
+	session = (struct SESSION_DATA_STRUCTURE*)data;
 
-	session = ( (struct SESSION_DATA_STRUCTURE*)data );
+	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
 
 	item = proto_tree_add_item(parent_tree, proto_dop, tvb, 0, -1, ENC_NA);
 	tree = proto_item_add_subtree(item, ett_dop);
diff --git a/asn1/dsp/packet-dsp-template.c b/asn1/dsp/packet-dsp-template.c
index fa4f9becd5..3a15d88504 100644
--- a/asn1/dsp/packet-dsp-template.c
+++ b/asn1/dsp/packet-dsp-template.c
@@ -81,18 +81,12 @@ dissect_dsp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void* da
 	const char *dsp_op_name;
 	asn1_ctx_t asn1_ctx;
 
-	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
-
-	/* do we have operation information from the ROS dissector?  */
-	if( data == NULL ){
-		if(parent_tree){
-			proto_tree_add_text(parent_tree, tvb, offset, -1,
-				"Internal error: can't get operation information from ROS dissector.");
-		}
-		return  0;
-	}
+	/* do we have operation information from the ROS dissector? */
+	if (data == NULL)
+		return 0;
+	session  = (struct SESSION_DATA_STRUCTURE*)data;
 
-	session  = ( (struct SESSION_DATA_STRUCTURE*)data);
+	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
 
 	item = proto_tree_add_item(parent_tree, proto_dsp, tvb, 0, -1, ENC_NA);
 	tree = proto_item_add_subtree(item, ett_dsp);
diff --git a/asn1/p1/packet-p1-template.c b/asn1/p1/packet-p1-template.c
index bd73ccdabb..10ca12e484 100644
--- a/asn1/p1/packet-p1-template.c
+++ b/asn1/p1/packet-p1-template.c
@@ -235,19 +235,13 @@ dissect_p1(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void* dat
 	asn1_ctx_t asn1_ctx;
 	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
 
-	/* save parent_tree so subdissectors can create new top nodes */
-	p1_initialize_content_globals (&asn1_ctx, parent_tree, TRUE);
-
-	/* do we have operation information from the ROS dissector?  */
-	if( data == NULL ){
-		if(parent_tree){
-			proto_tree_add_text(parent_tree, tvb, offset, -1,
-				"Internal error: can't get operation information from ROS dissector.");
-		}
+	/* do we have operation information from the ROS dissector? */
+	if (data == NULL)
 		return 0;
-	}
+	session  = (struct SESSION_DATA_STRUCTURE*)data;
 
-	session  = ( (struct SESSION_DATA_STRUCTURE*)data );
+	/* save parent_tree so subdissectors can create new top nodes */
+	p1_initialize_content_globals (&asn1_ctx, parent_tree, TRUE);
 
 	asn1_ctx.private_data = session;
 
diff --git a/asn1/ros/packet-ros-template.c b/asn1/ros/packet-ros-template.c
index 35dfad34da..967916d541 100644
--- a/asn1/ros/packet-ros-template.c
+++ b/asn1/ros/packet-ros-template.c
@@ -384,19 +384,14 @@ dissect_ros(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void* da
 	asn1_ctx_t asn1_ctx;
 	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
 
+	/* do we have application context from the acse dissector? */
+	if (data == NULL)
+		return 0;
+	asn1_ctx.private_data = data;
+
 	/* save parent_tree so subdissectors can create new top nodes */
 	top_tree=parent_tree;
 
-	/* do we have application context from the acse dissector?  */
-	if( !data){
-		if(parent_tree){
-			proto_tree_add_text(parent_tree, tvb, offset, -1,
-				"Internal error:can't get application context from ACSE dissector.");
-		}
-		return 0;
-	}
-
-    asn1_ctx.private_data = data;
 	conversation = find_or_create_conversation(pinfo);
 
 	/*
diff --git a/asn1/rtse/packet-rtse-template.c b/asn1/rtse/packet-rtse-template.c
index 83386f5d6e..27c26b854b 100644
--- a/asn1/rtse/packet-rtse-template.c
+++ b/asn1/rtse/packet-rtse-template.c
@@ -207,19 +207,13 @@ dissect_rtse(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void* d
 	asn1_ctx_t asn1_ctx;
 	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
 
-	/* save parent_tree so subdissectors can create new top nodes */
-	top_tree=parent_tree;
-
-	/* do we have application context from the acse dissector?  */
-	if( data == NULL ){
-		if(parent_tree){
-			proto_tree_add_text(parent_tree, tvb, offset, -1,
-				"Internal error:can't get application context from ACSE dissector.");
-		}
+	/* do we have application context from the acse dissector? */
+	if (data == NULL)
 		return 0;
-	}
+	session  = (struct SESSION_DATA_STRUCTURE*)data;
 
-	session  = ( (struct SESSION_DATA_STRUCTURE*)data);
+	/* save parent_tree so subdissectors can create new top nodes */
+	top_tree=parent_tree;
 
 	asn1_ctx.private_data = session;
 
diff --git a/epan/dissectors/packet-disp.c b/epan/dissectors/packet-disp.c
index 378fc29223..517cb5adc6 100644
--- a/epan/dissectors/packet-disp.c
+++ b/epan/dissectors/packet-disp.c
@@ -1514,18 +1514,12 @@ dissect_disp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void* d
 	const char *disp_op_name;
 	asn1_ctx_t asn1_ctx;
 
-	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
-
-	/* do we have operation information from the ROS dissector?  */
-	if( data == NULL ){
-		if(parent_tree){
-			proto_tree_add_text(parent_tree, tvb, offset, -1,
-				"Internal error: can't get operation information from ROS dissector.");
-		}
+	/* do we have operation information from the ROS dissector */
+	if (data == NULL)
 		return 0;
-	}
+	session  = (struct SESSION_DATA_STRUCTURE*)data;
 
-	session  = ((struct SESSION_DATA_STRUCTURE*)data);
+	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
 
 	asn1_ctx.private_data = session;
 
@@ -2061,7 +2055,7 @@ void proto_register_disp(void) {
         "ShadowErrorData", HFILL }},
 
 /*--- End of included file: packet-disp-hfarr.c ---*/
-#line 205 "../../asn1/disp/packet-disp-template.c"
+#line 199 "../../asn1/disp/packet-disp-template.c"
   };
 
   /* List of subtrees */
@@ -2126,7 +2120,7 @@ void proto_register_disp(void) {
     &ett_disp_T_signedShadowError,
 
 /*--- End of included file: packet-disp-ettarr.c ---*/
-#line 211 "../../asn1/disp/packet-disp-template.c"
+#line 205 "../../asn1/disp/packet-disp-template.c"
   };
   module_t *disp_module;
 
@@ -2165,7 +2159,7 @@ void proto_reg_handoff_disp(void) {
 
 
 /*--- End of included file: packet-disp-dis-tab.c ---*/
-#line 239 "../../asn1/disp/packet-disp-template.c"
+#line 233 "../../asn1/disp/packet-disp-template.c"
 
   /* APPLICATION CONTEXT */
 
diff --git a/epan/dissectors/packet-dop.c b/epan/dissectors/packet-dop.c
index ee56b73368..1731ff5e99 100644
--- a/epan/dissectors/packet-dop.c
+++ b/epan/dissectors/packet-dop.c
@@ -2091,18 +2091,12 @@ dissect_dop(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void* da
 	const char *dop_op_name;
 	asn1_ctx_t asn1_ctx;
 
-	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
-
-	/* do we have operation information from the ROS dissector?  */
-	if( data == NULL ){
-		if(parent_tree){
-			proto_tree_add_text(parent_tree, tvb, offset, -1,
-				"Internal error: can't get operation information from ROS dissector.");
-		}
-		return  0;
-	}
+	/* do we have operation information from the ROS dissector? */
+	if (data == NULL)
+		return 0;
+	session = (struct SESSION_DATA_STRUCTURE*)data;
 
-	session = ( (struct SESSION_DATA_STRUCTURE*)data );
+	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
 
 	item = proto_tree_add_item(parent_tree, proto_dop, tvb, 0, -1, ENC_NA);
 	tree = proto_item_add_subtree(item, ett_dop);
@@ -2971,7 +2965,7 @@ void proto_register_dop(void) {
         NULL, HFILL }},
 
 /*--- End of included file: packet-dop-hfarr.c ---*/
-#line 248 "../../asn1/dop/packet-dop-template.c"
+#line 242 "../../asn1/dop/packet-dop-template.c"
   };
 
   /* List of subtrees */
@@ -3050,7 +3044,7 @@ void proto_register_dop(void) {
     &ett_dop_GrantsAndDenials,
 
 /*--- End of included file: packet-dop-ettarr.c ---*/
-#line 255 "../../asn1/dop/packet-dop-template.c"
+#line 249 "../../asn1/dop/packet-dop-template.c"
   };
 
   static ei_register_info ei[] = {
@@ -3113,7 +3107,7 @@ void proto_reg_handoff_dop(void) {
 
 
 /*--- End of included file: packet-dop-dis-tab.c ---*/
-#line 295 "../../asn1/dop/packet-dop-template.c"
+#line 289 "../../asn1/dop/packet-dop-template.c"
   /* APPLICATION CONTEXT */
 
   oid_add_from_string("id-ac-directory-operational-binding-management","2.5.3.3");
diff --git a/epan/dissectors/packet-dsp.c b/epan/dissectors/packet-dsp.c
index 6a6cd16996..9c8d52429b 100644
--- a/epan/dissectors/packet-dsp.c
+++ b/epan/dissectors/packet-dsp.c
@@ -1803,18 +1803,12 @@ dissect_dsp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void* da
 	const char *dsp_op_name;
 	asn1_ctx_t asn1_ctx;
 
-	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
-
-	/* do we have operation information from the ROS dissector?  */
-	if( data == NULL ){
-		if(parent_tree){
-			proto_tree_add_text(parent_tree, tvb, offset, -1,
-				"Internal error: can't get operation information from ROS dissector.");
-		}
-		return  0;
-	}
+	/* do we have operation information from the ROS dissector? */
+	if (data == NULL)
+		return 0;
+	session  = (struct SESSION_DATA_STRUCTURE*)data;
 
-	session  = ( (struct SESSION_DATA_STRUCTURE*)data);
+	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
 
 	item = proto_tree_add_item(parent_tree, proto_dsp, tvb, 0, -1, ENC_NA);
 	tree = proto_item_add_subtree(item, ett_dsp);
@@ -2548,7 +2542,7 @@ void proto_register_dsp(void) {
         "EXTERNAL", HFILL }},
 
 /*--- End of included file: packet-dsp-hfarr.c ---*/
-#line 277 "../../asn1/dsp/packet-dsp-template.c"
+#line 271 "../../asn1/dsp/packet-dsp-template.c"
   };
 
   /* List of subtrees */
@@ -2630,7 +2624,7 @@ void proto_register_dsp(void) {
     &ett_dsp_T_basicLevels,
 
 /*--- End of included file: packet-dsp-ettarr.c ---*/
-#line 283 "../../asn1/dsp/packet-dsp-template.c"
+#line 277 "../../asn1/dsp/packet-dsp-template.c"
   };
   module_t *dsp_module;
 
@@ -2671,7 +2665,7 @@ void proto_reg_handoff_dsp(void) {
 
 
 /*--- End of included file: packet-dsp-dis-tab.c ---*/
-#line 313 "../../asn1/dsp/packet-dsp-template.c"
+#line 307 "../../asn1/dsp/packet-dsp-template.c"
 
   /* APPLICATION CONTEXT */
 
diff --git a/epan/dissectors/packet-hci_usb.c b/epan/dissectors/packet-hci_usb.c
index 6fdf2c08de..37be9330e6 100644
--- a/epan/dissectors/packet-hci_usb.c
+++ b/epan/dissectors/packet-hci_usb.c
@@ -106,13 +106,18 @@ dissect_hci_usb(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
     proto_tree     *titem = NULL;
     proto_item     *pitem = NULL;
     gint            offset = 0;
-    usb_conv_info_t *usb_conv_info = (usb_conv_info_t *)data;
+    usb_conv_info_t *usb_conv_info;
     tvbuff_t       *next_tvb = NULL;
     hci_data_t     *hci_data;
     gint            p2p_dir_save;
     guint32         session_id;
     fragment_head  *reassembled;
 
+    /* Reject the packet if data is NULL */
+    if (data == NULL)
+        return 0;
+    usb_conv_info = (usb_conv_info_t *)data;
+
     if (tvb_length_remaining(tvb, offset) <= 0)
         return 0;
 
@@ -121,8 +126,6 @@ dissect_hci_usb(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
 
     col_set_str(pinfo->cinfo, COL_PROTOCOL, "HCI_USB");
 
-    DISSECTOR_ASSERT(usb_conv_info);
-
     p2p_dir_save = pinfo->p2p_dir;
     pinfo->p2p_dir = usb_conv_info->direction;
 
diff --git a/epan/dissectors/packet-p1.c b/epan/dissectors/packet-p1.c
index 58b7d64aab..4881fe39a3 100644
--- a/epan/dissectors/packet-p1.c
+++ b/epan/dissectors/packet-p1.c
@@ -8356,19 +8356,13 @@ dissect_p1(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void* dat
 	asn1_ctx_t asn1_ctx;
 	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
 
-	/* save parent_tree so subdissectors can create new top nodes */
-	p1_initialize_content_globals (&asn1_ctx, parent_tree, TRUE);
-
-	/* do we have operation information from the ROS dissector?  */
-	if( data == NULL ){
-		if(parent_tree){
-			proto_tree_add_text(parent_tree, tvb, offset, -1,
-				"Internal error: can't get operation information from ROS dissector.");
-		}
+	/* do we have operation information from the ROS dissector? */
+	if (data == NULL)
 		return 0;
-	}
+	session  = (struct SESSION_DATA_STRUCTURE*)data;
 
-	session  = ( (struct SESSION_DATA_STRUCTURE*)data );
+	/* save parent_tree so subdissectors can create new top nodes */
+	p1_initialize_content_globals (&asn1_ctx, parent_tree, TRUE);
 
 	asn1_ctx.private_data = session;
 
@@ -10704,7 +10698,7 @@ void proto_register_p1(void) {
         NULL, HFILL }},
 
 /*--- End of included file: packet-p1-hfarr.c ---*/
-#line 326 "../../asn1/p1/packet-p1-template.c"
+#line 320 "../../asn1/p1/packet-p1-template.c"
   };
 
   /* List of subtrees */
@@ -10903,7 +10897,7 @@ void proto_register_p1(void) {
     &ett_p1_SEQUENCE_SIZE_1_ub_recipients_OF_PerRecipientProbeSubmissionFields,
 
 /*--- End of included file: packet-p1-ettarr.c ---*/
-#line 339 "../../asn1/p1/packet-p1-template.c"
+#line 333 "../../asn1/p1/packet-p1-template.c"
   };
 
   static ei_register_info ei[] = {
@@ -11106,7 +11100,7 @@ void proto_reg_handoff_p1(void) {
 
 
 /*--- End of included file: packet-p1-dis-tab.c ---*/
-#line 385 "../../asn1/p1/packet-p1-template.c"
+#line 379 "../../asn1/p1/packet-p1-template.c"
 
   /* APPLICATION CONTEXT */
 
diff --git a/epan/dissectors/packet-pw-atm.c b/epan/dissectors/packet-pw-atm.c
index 605559613b..89329f06ac 100644
--- a/epan/dissectors/packet-pw-atm.c
+++ b/epan/dissectors/packet-pw-atm.c
@@ -1145,8 +1145,12 @@ proto_item_append_text_cwb3_fields(proto_item * item, const pwatm_private_data_t
 static int
 dissect_control_word(tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree, void* data)
 {
-	pwatm_private_data_t* pd = (pwatm_private_data_t *)data;
-	DISSECTOR_ASSERT(pd != NULL);
+	pwatm_private_data_t* pd;
+
+	/* Reject the packet if data is NULL */
+	if (data == NULL)
+		return 0;
+	pd = (pwatm_private_data_t *)data;
 
 	/*
 	 * NB: do not touch columns -- keep info from previous dissector
@@ -1334,11 +1338,15 @@ dissect_control_word(tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree, voi
 static int
 dissect_cell_header(tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree, void * data)
 {
-	pwatm_private_data_t * pd = (pwatm_private_data_t *)data;
+	pwatm_private_data_t * pd;
 	gboolean               is_enough_data;
 	int                    dissect_size;
 
-	DISSECTOR_ASSERT (NULL != pd);
+	/* Reject the packet if data is NULL */
+	if (data == NULL)
+		return 0;
+	pd = (pwatm_private_data_t *)data;
+
 	pd->vpi	     = pd->vci = pd->pti = -1;
 	pd->cwb3.clp = pd->cwb3.m = pd->cwb3.v = pd->cwb3.rsv = pd->cwb3.u = pd->cwb3.e = -1;
 
diff --git a/epan/dissectors/packet-rfid-pn532-hci.c b/epan/dissectors/packet-rfid-pn532-hci.c
index d0ebef57c1..a5b8a50010 100644
--- a/epan/dissectors/packet-rfid-pn532-hci.c
+++ b/epan/dissectors/packet-rfid-pn532-hci.c
@@ -1,5 +1,5 @@
 /* packet-pn532_hci.c
- * Routines for NXP PN532 HCI Protocol 
+ * Routines for NXP PN532 HCI Protocol
  *
  * http://www.nxp.com/documents/user_manual/141520.pdf
  *
@@ -76,9 +76,12 @@ dissect_pn532_hci(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *dat
     guint16          packet_code;
     guint16          length;
     guint8           checksum;
-    usb_conv_info_t *usb_conv_info = (usb_conv_info_t *)data;
+    usb_conv_info_t *usb_conv_info;
 
-    DISSECTOR_ASSERT(usb_conv_info);
+    /* Reject the packet if data is NULL */
+    if (data == NULL)
+        return 0;
+    usb_conv_info = (usb_conv_info_t *)data;
 
     length = tvb_length_remaining(tvb, offset);
     if (length < 6) return offset;
diff --git a/epan/dissectors/packet-rfid-pn532.c b/epan/dissectors/packet-rfid-pn532.c
index 86c80d4bb0..83edbe701a 100644
--- a/epan/dissectors/packet-rfid-pn532.c
+++ b/epan/dissectors/packet-rfid-pn532.c
@@ -633,7 +633,7 @@ dissect_pn532(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
     tvbuff_t   *next_tvb;
     gint        offset = 0;
     command_data_t  *command_data = NULL;
-    usb_conv_info_t *usb_conv_info = (usb_conv_info_t *)data;
+    usb_conv_info_t *usb_conv_info;
     wmem_tree_key_t  key[5];
     guint32          bus_id;
     guint32          device_address;
@@ -643,6 +643,11 @@ dissect_pn532(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
     guint32          k_endpoint;
     guint32          k_frame_number;
 
+    /* Reject the packet if data is NULL */
+    if (data == NULL)
+        return 0;
+    usb_conv_info = (usb_conv_info_t *)data;
+
     col_set_str(pinfo->cinfo, COL_PROTOCOL, "PN532");
 
     item = proto_tree_add_item(tree, proto_pn532, tvb, 0, -1, ENC_NA);
@@ -657,8 +662,6 @@ dissect_pn532(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
 
     col_set_str(pinfo->cinfo, COL_INFO, val_to_str_ext_const(cmd, &pn532_commands_ext, "Unknown command"));
 
-    DISSECTOR_ASSERT(usb_conv_info);
-
     bus_id = usb_conv_info->bus_id;
     device_address = usb_conv_info->device_address;
     endpoint = usb_conv_info->endpoint;
diff --git a/epan/dissectors/packet-ros.c b/epan/dissectors/packet-ros.c
index 5048da771a..4aeefb72b9 100644
--- a/epan/dissectors/packet-ros.c
+++ b/epan/dissectors/packet-ros.c
@@ -1020,19 +1020,14 @@ dissect_ros(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void* da
 	asn1_ctx_t asn1_ctx;
 	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
 
+	/* do we have application context from the acse dissector? */
+	if (data == NULL)
+		return 0;
+	asn1_ctx.private_data = data;
+
 	/* save parent_tree so subdissectors can create new top nodes */
 	top_tree=parent_tree;
 
-	/* do we have application context from the acse dissector?  */
-	if( !data){
-		if(parent_tree){
-			proto_tree_add_text(parent_tree, tvb, offset, -1,
-				"Internal error:can't get application context from ACSE dissector.");
-		}
-		return 0;
-	}
-
-    asn1_ctx.private_data = data;
 	conversation = find_or_create_conversation(pinfo);
 
 	/*
@@ -1233,7 +1228,7 @@ void proto_register_ros(void) {
         "OBJECT_IDENTIFIER", HFILL }},
 
 /*--- End of included file: packet-ros-hfarr.c ---*/
-#line 488 "../../asn1/ros/packet-ros-template.c"
+#line 483 "../../asn1/ros/packet-ros-template.c"
   };
 
   /* List of subtrees */
@@ -1254,7 +1249,7 @@ void proto_register_ros(void) {
     &ett_ros_Code,
 
 /*--- End of included file: packet-ros-ettarr.c ---*/
-#line 495 "../../asn1/ros/packet-ros-template.c"
+#line 490 "../../asn1/ros/packet-ros-template.c"
   };
 
   static ei_register_info ei[] = {
diff --git a/epan/dissectors/packet-rtse.c b/epan/dissectors/packet-rtse.c
index 7e2607b816..2dd38cd793 100644
--- a/epan/dissectors/packet-rtse.c
+++ b/epan/dissectors/packet-rtse.c
@@ -763,19 +763,13 @@ dissect_rtse(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void* d
 	asn1_ctx_t asn1_ctx;
 	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
 
-	/* save parent_tree so subdissectors can create new top nodes */
-	top_tree=parent_tree;
-
-	/* do we have application context from the acse dissector?  */
-	if( data == NULL ){
-		if(parent_tree){
-			proto_tree_add_text(parent_tree, tvb, offset, -1,
-				"Internal error:can't get application context from ACSE dissector.");
-		}
+	/* do we have application context from the acse dissector? */
+	if (data == NULL)
 		return 0;
-	}
+	session  = (struct SESSION_DATA_STRUCTURE*)data;
 
-	session  = ( (struct SESSION_DATA_STRUCTURE*)data);
+	/* save parent_tree so subdissectors can create new top nodes */
+	top_tree=parent_tree;
 
 	asn1_ctx.private_data = session;
 
@@ -1010,7 +1004,7 @@ void proto_register_rtse(void) {
         NULL, HFILL }},
 
 /*--- End of included file: packet-rtse-hfarr.c ---*/
-#line 357 "../../asn1/rtse/packet-rtse-template.c"
+#line 351 "../../asn1/rtse/packet-rtse-template.c"
   };
 
   /* List of subtrees */
@@ -1032,7 +1026,7 @@ void proto_register_rtse(void) {
     &ett_rtse_CallingSSuserReference,
 
 /*--- End of included file: packet-rtse-ettarr.c ---*/
-#line 366 "../../asn1/rtse/packet-rtse-template.c"
+#line 360 "../../asn1/rtse/packet-rtse-template.c"
   };
 
   static ei_register_info ei[] = {
diff --git a/epan/dissectors/packet-usb-ccid.c b/epan/dissectors/packet-usb-ccid.c
index ce46a504ce..9431085afe 100644
--- a/epan/dissectors/packet-usb-ccid.c
+++ b/epan/dissectors/packet-usb-ccid.c
@@ -350,9 +350,12 @@ dissect_ccid(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
     proto_tree *ccid_tree;
     guint8      cmd;
     tvbuff_t   *next_tvb;
-    usb_conv_info_t  *usb_conv_info = (usb_conv_info_t *)data;
+    usb_conv_info_t  *usb_conv_info;
 
-    DISSECTOR_ASSERT(usb_conv_info);
+    /* Reject the packet if data is NULL */
+    if (data == NULL)
+        return 0;
+    usb_conv_info = (usb_conv_info_t *)data;
 
     col_set_str(pinfo->cinfo, COL_PROTOCOL, "USBCCID");
     col_set_str(pinfo->cinfo, COL_INFO,     "CCID Packet");