NBAP: avoid dereferencing a NULL pointer

Bug: 11602
Change-Id: I56b9db19eca416c288f36c1f3a4faa7e22b38c8f
Reviewed-on: https://code.wireshark.org/review/11109
Reviewed-by: Pascal Quantin <pascal.quantin@gmail.com>
Petri-Dish: Pascal Quantin <pascal.quantin@gmail.com>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Alexis La Goutte <alexis.lagoutte@gmail.com>

1 files changed, 37 insertions, 34 deletions

diff --git a/epan/dissectors/packet-nbap.c b/epan/dissectors/packet-nbap.c
index 5055a53b5d..49dc4a700a 100644
--- a/epan/dissectors/packet-nbap.c
+++ b/epan/dissectors/packet-nbap.c
@@ -10027,7 +10027,7 @@ dissect_nbap_AddorDeleteIndicator(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t
 
 static int
 dissect_nbap_CFN(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 2143 "../../asn1/nbap/nbap.cnf"
+#line 2146 "../../asn1/nbap/nbap.cnf"
   offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
                                                             0U, 255U, &cfn, FALSE);
 
@@ -10280,7 +10280,7 @@ dissect_nbap_AvailabilityStatus(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *a
 
 static int
 dissect_nbap_HSDSCH_RNTI(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 2108 "../../asn1/nbap/nbap.cnf"
+#line 2111 "../../asn1/nbap/nbap.cnf"
 umts_fp_conversation_info_t *umts_fp_conversation_info = NULL;
 address     null_addr;
 conversation_t   *conversation = NULL;
@@ -11502,7 +11502,7 @@ dissect_nbap_Common_E_DCH_Resource_Combination_InfoList(tvbuff_t *tvb _U_, int o
 
 static int
 dissect_nbap_Common_MACFlow_ID(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1967 "../../asn1/nbap/nbap.cnf"
+#line 1970 "../../asn1/nbap/nbap.cnf"
 
   offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
                                                             0U, maxNrOfCommonMACFlows_1, &common_macdflow_id, FALSE);
@@ -11636,7 +11636,7 @@ dissect_nbap_E_DCH_MACdFlow_Multiplexing_List(tvbuff_t *tvb _U_, int offset _U_,
 
 static int
 dissect_nbap_LogicalChannelID(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1620 "../../asn1/nbap/nbap.cnf"
+#line 1623 "../../asn1/nbap/nbap.cnf"
     /* Set logical channel id for this entry*/
   offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
                                                             1U, 15U, &logical_channel_id, FALSE);
@@ -11655,7 +11655,7 @@ dissect_nbap_LogicalChannelID(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *act
 
 static int
 dissect_nbap_MAC_PDU_SizeExtended(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1723 "../../asn1/nbap/nbap.cnf"
+#line 1726 "../../asn1/nbap/nbap.cnf"
   offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
                                                             1U, 1504U, NULL, TRUE);
 
@@ -12078,7 +12078,7 @@ static const per_sequence_t CommonMACFlow_Specific_InfoItem_sequence[] = {
 
 static int
 dissect_nbap_CommonMACFlow_Specific_InfoItem(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1974 "../../asn1/nbap/nbap.cnf"
+#line 1977 "../../asn1/nbap/nbap.cnf"
     address     dst_addr;
     transportLayerAddress_ipv4 = 0;
     BindingID_port = 0;
@@ -12123,7 +12123,7 @@ dissect_nbap_CommonMACFlow_Specific_InfoList(tvbuff_t *tvb _U_, int offset _U_,
 
 static int
 dissect_nbap_MACdPDU_Size(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1611 "../../asn1/nbap/nbap.cnf"
+#line 1614 "../../asn1/nbap/nbap.cnf"
   offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
                                                             1U, 5000U, &MACdPDU_Size, TRUE);
 
@@ -13343,7 +13343,7 @@ dissect_nbap_CriticalityDiagnostics(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_
 
 static int
 dissect_nbap_CRNC_CommunicationContextID(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 2082 "../../asn1/nbap/nbap.cnf"
+#line 2085 "../../asn1/nbap/nbap.cnf"
   offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
                                                             0U, 1048575U, &com_context_id, FALSE);
 
@@ -18027,7 +18027,7 @@ dissect_nbap_E_DCH_HARQ_Combining_Capability(tvbuff_t *tvb _U_, int offset _U_,
 
 static int
 dissect_nbap_E_DCH_DDI_Value(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1601 "../../asn1/nbap/nbap.cnf"
+#line 1604 "../../asn1/nbap/nbap.cnf"
 
   offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
                                                             0U, 62U, &e_dch_ddi_value, FALSE);
@@ -18161,7 +18161,7 @@ static const per_sequence_t E_DCH_LogicalChannelInformationItem_sequence[] = {
 
 static int
 dissect_nbap_E_DCH_LogicalChannelInformationItem(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1598 "../../asn1/nbap/nbap.cnf"
+#line 1601 "../../asn1/nbap/nbap.cnf"
     num_items++;
 
 
@@ -18178,7 +18178,7 @@ static const per_sequence_t E_DCH_LogicalChannelInformation_sequence_of[1] = {
 
 static int
 dissect_nbap_E_DCH_LogicalChannelInformation(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1591 "../../asn1/nbap/nbap.cnf"
+#line 1594 "../../asn1/nbap/nbap.cnf"
     num_items = 0;
 
   offset = dissect_per_constrained_sequence_of(tvb, offset, actx, tree, hf_index,
@@ -18211,7 +18211,7 @@ static const per_sequence_t E_DCH_MACdFlow_Specific_InfoItem_sequence[] = {
 
 static int
 dissect_nbap_E_DCH_MACdFlow_Specific_InfoItem(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1353 "../../asn1/nbap/nbap.cnf"
+#line 1356 "../../asn1/nbap/nbap.cnf"
 umts_fp_conversation_info_t *p_conv_data = NULL;
 address     null_addr;
 conversation_t   *p_conv;
@@ -18394,7 +18394,7 @@ static const per_sequence_t E_DCH_LogicalChannelToModifyItem_sequence[] = {
 
 static int
 dissect_nbap_E_DCH_LogicalChannelToModifyItem(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1586 "../../asn1/nbap/nbap.cnf"
+#line 1589 "../../asn1/nbap/nbap.cnf"
 
   offset = dissect_per_sequence(tvb, offset, actx, tree, hf_index,
                                    ett_nbap_E_DCH_LogicalChannelToModifyItem, E_DCH_LogicalChannelToModifyItem_sequence);
@@ -18469,7 +18469,7 @@ static const per_sequence_t E_DCH_MACdFlow_Specific_InfoItem_to_Modify_sequence[
 
 static int
 dissect_nbap_E_DCH_MACdFlow_Specific_InfoItem_to_Modify(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1494 "../../asn1/nbap/nbap.cnf"
+#line 1497 "../../asn1/nbap/nbap.cnf"
 guint32 no_ddi_entries, i;
 address     null_addr;
 nbap_edch_port_info_t *old_info;
@@ -18611,7 +18611,7 @@ static const per_sequence_t E_DCH_FDD_Information_to_Modify_sequence[] = {
 
 static int
 dissect_nbap_E_DCH_FDD_Information_to_Modify(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1406 "../../asn1/nbap/nbap.cnf"
+#line 1409 "../../asn1/nbap/nbap.cnf"
 
 address     dst_addr, null_addr;
 conversation_t *conversation,*old_conversation = NULL;
@@ -23303,7 +23303,7 @@ static const per_sequence_t HSDSCH_Common_System_InformationFDD_sequence[] = {
 
 static int
 dissect_nbap_HSDSCH_Common_System_InformationFDD(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1994 "../../asn1/nbap/nbap.cnf"
+#line 1997 "../../asn1/nbap/nbap.cnf"
 /*
  * 5.1.6 High Speed Downlink Shared Channels
  * The Data Transfer procedure is used to transfer a HS-DSCH DATA FRAME (TYPE 1, TYPE 2 [FDD and 1.28Mcps
@@ -23464,7 +23464,7 @@ static const per_sequence_t HSDSCH_MACdFlow_Specific_InfoItem_sequence[] = {
 
 static int
 dissect_nbap_HSDSCH_MACdFlow_Specific_InfoItem(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1701 "../../asn1/nbap/nbap.cnf"
+#line 1704 "../../asn1/nbap/nbap.cnf"
 
 
     address     dst_addr;
@@ -23567,7 +23567,7 @@ static const value_string nbap_RLC_Mode_vals[] = {
 
 static int
 dissect_nbap_RLC_Mode(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1628 "../../asn1/nbap/nbap.cnf"
+#line 1631 "../../asn1/nbap/nbap.cnf"
     guint32 rlc_mode;
 
   offset = dissect_per_enumerated(tvb, offset, actx, tree, hf_index,
@@ -23608,7 +23608,7 @@ static const per_sequence_t PriorityQueue_InfoItem_sequence[] = {
 
 static int
 dissect_nbap_PriorityQueue_InfoItem(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1692 "../../asn1/nbap/nbap.cnf"
+#line 1695 "../../asn1/nbap/nbap.cnf"
     num_items++;
 
 
@@ -23642,7 +23642,7 @@ static const per_sequence_t HSDSCH_MACdFlows_Information_sequence[] = {
 
 static int
 dissect_nbap_HSDSCH_MACdFlows_Information(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1652 "../../asn1/nbap/nbap.cnf"
+#line 1655 "../../asn1/nbap/nbap.cnf"
 
     int protocol_ie_id;
     guint32 i;
@@ -23686,7 +23686,7 @@ dissect_nbap_HSDSCH_MACdFlows_Information(tvbuff_t *tvb _U_, int offset _U_, asn
 
 static int
 dissect_nbap_T_hSDSCH_Physical_Layer_Category(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1645 "../../asn1/nbap/nbap.cnf"
+#line 1648 "../../asn1/nbap/nbap.cnf"
     guint32 hsdsch_physical_layer_category;
 
   offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
@@ -23754,7 +23754,7 @@ static const per_sequence_t HSDSCH_FDD_Information_sequence[] = {
 
 static int
 dissect_nbap_HSDSCH_FDD_Information(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1753 "../../asn1/nbap/nbap.cnf"
+#line 1756 "../../asn1/nbap/nbap.cnf"
 /*
  * Collect the information about the HSDSCH MACdFlows set up conversation(s) and set the conversation data.
  */
@@ -23891,7 +23891,7 @@ static const per_sequence_t HSDSCH_MACdFlow_Specific_InfoItem_to_Modify_sequence
 
 static int
 dissect_nbap_HSDSCH_MACdFlow_Specific_InfoItem_to_Modify(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1842 "../../asn1/nbap/nbap.cnf"
+#line 1845 "../../asn1/nbap/nbap.cnf"
     address     dst_addr;
     transportLayerAddress_ipv4 = 0;
     BindingID_port = 0;
@@ -23949,7 +23949,7 @@ static const per_sequence_t PriorityQueue_InfoItem_to_Add_sequence[] = {
 
 static int
 dissect_nbap_PriorityQueue_InfoItem_to_Add(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1695 "../../asn1/nbap/nbap.cnf"
+#line 1698 "../../asn1/nbap/nbap.cnf"
     num_items = 1;
 
 
@@ -24084,7 +24084,7 @@ static const per_sequence_t HSDSCH_Information_to_Modify_sequence[] = {
 
 static int
 dissect_nbap_HSDSCH_Information_to_Modify(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1862 "../../asn1/nbap/nbap.cnf"
+#line 1865 "../../asn1/nbap/nbap.cnf"
 /*
  * This is pretty much the same like if we setup a previous flow
  */
@@ -24206,7 +24206,7 @@ static const value_string nbap_HSDSCH_MACdPDUSizeFormat_vals[] = {
 
 static int
 dissect_nbap_HSDSCH_MACdPDUSizeFormat(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1730 "../../asn1/nbap/nbap.cnf"
+#line 1733 "../../asn1/nbap/nbap.cnf"
 /*
  * Removed 10 Aug. 2012, I'm not sure if this was right, it wrongfully
  * set some packets as type 2 for HSDHCH modified items.
@@ -24317,7 +24317,7 @@ static const per_sequence_t HSDSCH_MACdFlow_Specific_InformationResp_Item_sequen
 
 static int
 dissect_nbap_HSDSCH_MACdFlow_Specific_InformationResp_Item(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1698 "../../asn1/nbap/nbap.cnf"
+#line 1701 "../../asn1/nbap/nbap.cnf"
     num_items++;
 
 
@@ -24733,7 +24733,7 @@ static const per_sequence_t HSDSCH_Paging_System_InformationFDD_sequence[] = {
 
 static int
 dissect_nbap_HSDSCH_Paging_System_InformationFDD(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 2072 "../../asn1/nbap/nbap.cnf"
+#line 2075 "../../asn1/nbap/nbap.cnf"
   /*
   g_warning("HS-DSCH Type 3 NOT Implemented!");
   */
@@ -24927,7 +24927,7 @@ static const per_sequence_t HSDSCH_MACdFlows_to_Delete_Item_sequence[] = {
 
 static int
 dissect_nbap_HSDSCH_MACdFlows_to_Delete_Item(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1689 "../../asn1/nbap/nbap.cnf"
+#line 1692 "../../asn1/nbap/nbap.cnf"
     num_items++;
 
 
@@ -24944,7 +24944,7 @@ static const per_sequence_t HSDSCH_MACdFlows_to_Delete_sequence_of[1] = {
 
 static int
 dissect_nbap_HSDSCH_MACdFlows_to_Delete(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1684 "../../asn1/nbap/nbap.cnf"
+#line 1687 "../../asn1/nbap/nbap.cnf"
     num_items = 0;
 
 
@@ -28046,7 +28046,7 @@ dissect_nbap_NI_Information(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx
 
 static int
 dissect_nbap_NodeB_CommunicationContextID(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 2086 "../../asn1/nbap/nbap.cnf"
+#line 2089 "../../asn1/nbap/nbap.cnf"
 /*Set up and map that maps Node-B ids to CRNC ids, since often you only have one of them present in nbap*/
 nbap_com_context_id_t *cur_val;
 
@@ -28780,7 +28780,7 @@ dissect_nbap_RL_Specific_E_DCH_Information_Item(tvbuff_t *tvb _U_, int offset _U
 #line 1244 "../../asn1/nbap/nbap.cnf"
 address     dst_addr, null_addr;
 conversation_t *conversation;
-umts_fp_conversation_info_t *umts_fp_conversation_info;
+umts_fp_conversation_info_t *umts_fp_conversation_info = NULL;
 nbap_edch_port_info_t *old_info = NULL;
 
 transportLayerAddress_ipv4 = 0;
@@ -28802,11 +28802,14 @@ BindingID_port = 0;
         conversation = find_conversation(actx->pinfo->fd->num,&dst_addr,
             &null_addr, PT_UDP, BindingID_port,
             0, NO_ADDR_B|NO_PORT_B);
+        if (conversation) {
+            umts_fp_conversation_info = (umts_fp_conversation_info_t*)conversation_get_proto_data(conversation, proto_fp);
+        }
 
         /* We must also check if this port is about to be overriden, if that's the case we
          * might already have a DCH entry on this port which should be overwritten
          */
-        if (conversation == NULL || ((umts_fp_conversation_info_t*)conversation_get_proto_data(conversation, proto_fp))->channel == CHANNEL_DCH) {
+        if ((conversation == NULL) || (umts_fp_conversation_info && umts_fp_conversation_info->channel == CHANNEL_DCH)) {
 
 
 
@@ -41060,7 +41063,7 @@ col_set_str(actx->pinfo->cinfo, COL_INFO,"RadioLinkReconfigurationCommit ");
 actx->pinfo->link_dir=P2P_DIR_DL;
 
 
-#line 2135 "../../asn1/nbap/nbap.cnf"
+#line 2138 "../../asn1/nbap/nbap.cnf"
 /*
  * Here we need to signal the CFN value, down to FP so
  * that lowert layers know when a reconfiguration becomes active