Upgrade to tcpdump 4.9.0.

From CHANGES:

  Wednesday January 18, 2017 devel.fx.lebail@orange.fr
  Summary for 4.9.0 tcpdump release
    General updates:
    Improve separation frontend/backend (tcpdump/libnetdissect)
    Don't require IPv6 library support in order to support IPv6 addresses
    Introduce data types to use for integral values in packet structures
    Fix display of timestamps with -tt, -ttt and -ttttt options
    Fix some heap overflows found with American Fuzzy Lop by Hanno Boeck and others
        (More information in the log with CVE-2016-* and CVE-2017-*)
    Change the way protocols print link-layer addresses (Fix heap overflows
        in CALM-FAST and GeoNetworking printers)
    Pass correct caplen value to ether_print() and some other functions
    Fix lookup_nsap() to match what isonsap_string() expects
    Clean up relative time stamp printing (Fix an array overflow)
    Fix some alignment issues with GCC on Solaris 10 SPARC
    Add some ND_TTEST_/ND_TCHECK_ macros to simplify writing bounds checks
    Add a fn_printztn() which returns the number of bytes processed
    Add nd_init() and nd_cleanup() functions. Improve libsmi support
    Add CONTRIBUTING file
    Add a summary comment in all printers
    Compile with more warning options in devel mode if supported (-Wcast-qual, ...)
    Fix some leaks found by Valgrind/Memcheck
    Fix a bunch of de-constifications
    Squelch some Coverity warnings and some compiler warnings
    Update Coverity and Travis-CI setup
    Update Visual Studio files

    Frontend:
    Fix capsicum support to work with zerocopy buffers in bpf
    Try opening interfaces by name first, then by name-as-index
    Work around pcap_create() failures fetching time stamp type lists
    Fix a segmentation fault with 'tcpdump -J'
    Improve addrtostr6() bounds checking
    Add exit_tcpdump() function
    Don't drop CAP_SYS_CHROOT before chrooting
    Fixes issue where statistics not reported when -G and -W options used

    New printers supporting:
    Generic Protocol Extension for VXLAN (VXLAN-GPE)
    Home Networking Control Protocol (HNCP), RFCs 7787 and 7788
    Locator/Identifier Separation Protocol (LISP), type 3 and type 4 packets
    Marvell Extended Distributed Switch Architecture header (MEDSA)
    Network Service Header (NSH)
    REdis Serialization Protocol (RESP)

    Updated printers:
    802.11: Beginnings of 11ac radiotap support
    802.11: Check the Protected bit for management frames
    802.11: Do bounds checking on last_presentp before dereferencing it (Fix a heap overflow)
    802.11: Fix the radiotap printer to handle the special bits correctly
    802.11: If we have the MCS field, it's 11n
    802.11: Only print unknown frame type or subtype messages once
    802.11: Radiotap dBm values get printed as dB; Update a test output accordingly
    802.11: Source and destination addresses were backwards
    AH: Add a bounds check
    AH: Report to our caller that dissection failed if a bounds check fails
    AP1394: Print src > dst, not dst > src
    ARP: Don't assume the target hardware address is <= 6 octets long (Fix a heap overflow)
    ATALK: Add bounds and length checks (Fix heap overflows)
    ATM: Add some bounds checks (Fix a heap overflow)
    ATM: Fix an incorrect bounds check
    BFD: Update specification from draft to RFC 5880
    BFD: Update to print optional authentication field
    BGP: Add decoding of ADD-PATH capability
    BGP: Add support for the AIGP attribute (RFC7311)
    BGP: Print LARGE_COMMUNITY Path Attribute
    BGP: Update BGP numbers from IANA; Print minor values for FSM notification
    BOOTP: Add a bounds check
    Babel: Add decoder for source-specific extension
    CDP: Filter out non-printable characters
    CFM: Fixes to match the IEEE standard, additional bounds and length checks
    CSLIP: Add more bounds checks (Fix a heap overflow)
    ClassicalIPoATM: Add a bounds check on LLC+SNAP header (Fix a heap overflow)
    DHCP: Fix MUDURL and TZ options
    DHCPv6: Process MUDURL and TZ options
    DHCPv6: Update Status Codes with RFCs/IANA names
    DNS: Represent the "DNSSEC OK" bit as "DO" instead of "OK". Add a test case
    DTP: Improve packet integrity checks
    EGP: Fix bounds checks
    ESP: Don't use OpenSSL_add_all_algorithms() in OpenSSL 1.1.0 or later
    ESP: Handle OpenSSL 1.1.x
    Ethernet: Add some bounds checking before calling isoclns_print (Fix a heap overflow)
    Ethernet: Print the Length/Type field as length when needed
    FDDI: Fix -e output for FDDI
    FR: Add some packet-length checks and improve Q.933 printing (Fix heap overflows)
    GRE: Add some bounds checks (Fix heap overflows)
    Geneve: Fix error message with invalid option length; Update list option classes
    HNCP: Fix incorrect time interval format. Fix handling of IPv4 prefixes
    ICMP6: Fetch a 32-bit big-endian quantity with EXTRACT_32BITS()
    ICMP6: dagid is always an IPv6 address, not an opaque 128-bit string
    IGMP: Add a length check
    IP: Add a bounds check (Fix a heap overflow)
    IP: Check before fetching the protocol version (Fix a heap overflow)
    IP: Don't try to dissect if IP version != 4 (Fix a heap overflow)
    IP: Stop processing IPPROTO_ values once we hit IPPROTO_IPCOMP
    IPComp: Check whether we have the CPI before we fetch it (Fix a heap overflow)
    IPoFC: Fix -e output (IP-over-Fibre Channel)
    IPv6: Don't overwrite the destination IPv6 address for routing headers
    IPv6: Fix header printing
    IPv6: Stop processing IPPROTO_ values once we hit IPPROTO_IPCOMP
    ISAKMP: Clean up parsing of IKEv2 Security Associations
    ISOCLNS/IS-IS: Add support for Purge Originator Identifier (RFC6232) and test cases
    ISOCLNS/IS-IS: Don't overwrite packet data when checking the signature
    ISOCLNS/IS-IS: Filter out non-printable characters
    ISOCLNS/IS-IS: Fix segmentation faults
    ISOCLNS/IS-IS: Have signature_verify() do the copying and clearing
    ISOCLNS: Add some bounds checks
    Juniper: Make sure a Juniper header TLV isn't bigger than what's left in the packet (Fix a heap overflow)
    LLC/SNAP: With -e, print the LLC header before the SNAP header; without it, cut the SNAP header
    LLC: Add a bounds check (Fix a heap overflow)
    LLC: Clean up printing of LLC packets
    LLC: Fix the printing of RFC 948-style IP packets
    LLC: Skip the LLC and SNAP headers with -x for 802.11 and some other protocols
    LLDP: Implement IANA OUI and LLDP MUD option
    MPLS LSP ping: Update printing for RFC 4379, bug fixes, more bounds checks
    MPLS: "length" is now the *remaining* packet length
    MPLS: Add bounds and length checks (Fix a heap overflow)
    NFS: Add a test that makes unaligned accesses
    NFS: Don't assume the ONC RPC header is nicely aligned
    NFS: Don't overflow the Opaque_Handle buffer (Fix a segmentation fault)
    NFS: Don't run past the end of an NFSv3 file handle
    OLSR: Add a test to cover a HNA sgw case
    OLSR: Fix 'Advertised networks' count
    OLSR: Fix printing of smart-gateway HNAs in IPv4
    OSPF: Add a bounds check for the Hello packet options
    OSPF: Do more bounds checking
    OSPF: Fix a segmentation fault
    OSPF: Fix printing 'ospf_topology_values' default
    OTV: Add missing bounds checks
    PGM: Print the formatted IP address, not the raw binary address, as a string
    PIM: Add some bounds checking (Fix a heap overflow)
    PIMv2: Fix checksumming of Register messages
    PPI: Pass an adjusted struct pcap_pkthdr to the sub-printer
    PPP: Add some bounds checks (Fix a heap overflow)
    PPP: Report invalid PAP AACK/ANAK packets
    Q.933: Add a missing bounds check
    RADIUS: Add Value 13 "VLAN" to Tunnel-Type attribute
    RADIUS: Filter out non-printable characters
    RADIUS: Translate UDP/1700 as RADIUS
    RESP: Do better checking of RESP packets
    RPKI-RTR: Add a return value check for "fn_printn" call
    RPKI-RTR: Remove printing when truncated condition already detected
    RPL: Fix 'Consistency Check' control code
    RPL: Fix suboption print
    RSVP: An INTEGRITY object in a submessage covers only the submessage
    RSVP: Fix an infinite loop; Add bounds and length checks
    RSVP: Fix some if statements missing brackets
    RSVP: Have signature_verify() do the copying and clearing
    RTCP: Add some bounds checks
    RTP: Add some bounds checks, fix two segmentation faults
    SCTP: Do more bounds checking
    SFLOW: Fix bounds checking
    SLOW: Fix bugs, add checks
    SMB: Before fetching the flags2 field, make sure we have it
    SMB: Do bounds checks on NBNS resource types and resource data lengths
    SNMP: Clean up the "have libsmi but no modules loaded" case
    SNMP: Clean up the object abbreviation list and fix the code to match them
    SNMP: Do bounds checks when printing character and octet strings
    SNMP: Improve ASN.1 bounds checks
    SNMP: More bounds and length checks
    STP: Add a bunch of bounds checks, and fix some printing (Fix heap overflows)
    STP: Filter out non-printable characters
    TCP: Add bounds and length checks for packets with TCP option 20
    TCP: Correct TCP option Kind value for TCP Auth and add SCPS-TP
    TCP: Fix two bounds checks (Fix heap overflows)
    TCP: Make sure we have the data offset field before fetching it (Fix a heap overflow)
    TCP: Put TCP-AO option decoding right
    TFTP: Don't use strchr() to scan packet data (Fix a heap overflow)
    Telnet: Add some bounds checks
    TokenRing: Fix -e output
    UDLD: Fix an infinite loop
    UDP: Add a bounds check (Fix a heap overflow)
    UDP: Check against the packet length first
    UDP: Don't do the DDP-over-UDP heuristic check up front
    VAT: Add some bounds checks
    VTP: Add a test on Mgmt Domain Name length
    VTP: Add bounds checks and filter out non-printable characters
    VXLAN: Add a bound check and a test case
    ZeroMQ: Fix an infinite loop

  Tuesday April 14, 2015 guy@alum.mit.edu
  Summary for 4.8.0 tcpdump release
        Fix "-x" for Apple PKTAP and PPI packets

Bug: N/A
Test: "adb shell tcpdump"
Change-Id: I81df72cf1ebdbe61c5b6069d8532ae817570f23f
diff --git a/print-stp.c b/print-stp.c
index 93bb600..2f5c917 100644
--- a/print-stp.c
+++ b/print-stp.c
@@ -5,20 +5,20 @@
  * BSD-style license that accompanies tcpdump or the GNU General
  * Public License
  *
- * Format and print IEEE 802.1d spanning tree protocol packets.
  * Contributed by Lennert Buytenhek <buytenh@gnu.org>
  */
 
-#define NETDISSECT_REWORKED
+/* \summary: IEEE 802.1d Spanning Tree Protocol (STP) printer */
+
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
-#include <tcpdump-stdinc.h>
+#include <netdissect-stdinc.h>
 
 #include <stdio.h>
 
-#include "interface.h"
+#include "netdissect.h"
 #include "extract.h"
 
 #define	RSTP_EXTRACT_PORT_ROLE(x) (((x)&0x0C)>>2)
@@ -84,6 +84,8 @@
     { 0, NULL}
 };
 
+#define ND_TCHECK_BRIDGE_ID(p) ND_TCHECK2(*(p), 8)
+
 static char *
 stp_print_bridge_id(const u_char *p)
 {
@@ -96,22 +98,25 @@
     return bridge_id_str;
 }
 
-static void
+static int
 stp_print_config_bpdu(netdissect_options *ndo, const struct stp_bpdu_ *stp_bpdu,
                       u_int length)
 {
+    ND_TCHECK(stp_bpdu->flags);
     ND_PRINT((ndo, ", Flags [%s]",
            bittok2str(stp_bpdu_flag_values, "none", stp_bpdu->flags)));
 
+    ND_TCHECK(stp_bpdu->port_id);
     ND_PRINT((ndo, ", bridge-id %s.%04x, length %u",
            stp_print_bridge_id((const u_char *)&stp_bpdu->bridge_id),
            EXTRACT_16BITS(&stp_bpdu->port_id), length));
 
     /* in non-verbose mode just print the bridge-id */
     if (!ndo->ndo_vflag) {
-        return;
+        return 1;
     }
 
+    ND_TCHECK(stp_bpdu->forward_delay);
     ND_PRINT((ndo, "\n\tmessage-age %.2fs, max-age %.2fs"
            ", hello-time %.2fs, forwarding-delay %.2fs",
            (float)EXTRACT_16BITS(&stp_bpdu->message_age) / STP_TIME_BASE,
@@ -129,6 +134,10 @@
                tok2str(rstp_obj_port_role_values, "Unknown",
                        RSTP_EXTRACT_PORT_ROLE(stp_bpdu->flags))));
     }
+    return 1;
+
+trunc:
+    return 0;
 }
 
 /*
@@ -226,8 +235,7 @@
 #define SPB_BPDU_AGREEMENT_RES2_OFFSET    SPB_BPDU_AGREEMENT_RES1_OFFSET + 4
 #define SPB_BPDU_AGREEMENT_DIGEST_OFFSET  SPB_BPDU_AGREEMENT_RES2_OFFSET + 4
 
-
-static void
+static int
 stp_print_mstp_bpdu(netdissect_options *ndo, const struct stp_bpdu_ *stp_bpdu,
                     u_int length)
 {
@@ -245,22 +253,26 @@
      * in non-verbose mode just print the flags.
      */
     if (!ndo->ndo_vflag) {
-        return;
+        return 1;
     }
 
     ND_PRINT((ndo, "\n\tport-role %s, ",
            tok2str(rstp_obj_port_role_values, "Unknown",
                    RSTP_EXTRACT_PORT_ROLE(stp_bpdu->flags))));
 
-    ND_PRINT((ndo, "CIST root-id %s, CIST ext-pathcost %u ",
+    ND_TCHECK(stp_bpdu->root_path_cost);
+    ND_PRINT((ndo, "CIST root-id %s, CIST ext-pathcost %u",
            stp_print_bridge_id((const u_char *)&stp_bpdu->root_id),
            EXTRACT_32BITS(&stp_bpdu->root_path_cost)));
 
+    ND_TCHECK(stp_bpdu->bridge_id);
     ND_PRINT((ndo, "\n\tCIST regional-root-id %s, ",
            stp_print_bridge_id((const u_char *)&stp_bpdu->bridge_id)));
 
-    ND_PRINT((ndo, "CIST port-id %04x, ", EXTRACT_16BITS(&stp_bpdu->port_id)));
+    ND_TCHECK(stp_bpdu->port_id);
+    ND_PRINT((ndo, "CIST port-id %04x,", EXTRACT_16BITS(&stp_bpdu->port_id)));
 
+    ND_TCHECK(stp_bpdu->forward_delay);
     ND_PRINT((ndo, "\n\tmessage-age %.2fs, max-age %.2fs"
            ", hello-time %.2fs, forwarding-delay %.2fs",
            (float)EXTRACT_16BITS(&stp_bpdu->message_age) / STP_TIME_BASE,
@@ -268,30 +280,40 @@
            (float)EXTRACT_16BITS(&stp_bpdu->hello_time) / STP_TIME_BASE,
            (float)EXTRACT_16BITS(&stp_bpdu->forward_delay) / STP_TIME_BASE));
 
+    ND_TCHECK_16BITS(ptr + MST_BPDU_VER3_LEN_OFFSET);
     ND_PRINT((ndo, "\n\tv3len %d, ", EXTRACT_16BITS(ptr + MST_BPDU_VER3_LEN_OFFSET)));
-    ND_PRINT((ndo, "MCID Name %s, rev %u, "
+    ND_TCHECK_32BITS(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 12);
+    ND_PRINT((ndo, "MCID Name "));
+    if (fn_printzp(ndo, ptr + MST_BPDU_CONFIG_NAME_OFFSET, 32, ndo->ndo_snapend))
+	goto trunc;
+    ND_PRINT((ndo, ", rev %u,"
             "\n\t\tdigest %08x%08x%08x%08x, ",
-            ptr + MST_BPDU_CONFIG_NAME_OFFSET,
 	          EXTRACT_16BITS(ptr + MST_BPDU_CONFIG_NAME_OFFSET + 32),
-      	    EXTRACT_32BITS(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET),
-        	  EXTRACT_32BITS(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 4),
+	          EXTRACT_32BITS(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET),
+	          EXTRACT_32BITS(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 4),
 	          EXTRACT_32BITS(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 8),
 	          EXTRACT_32BITS(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 12)));
 
-    ND_PRINT((ndo, "CIST int-root-pathcost %u, ",
+    ND_TCHECK_32BITS(ptr + MST_BPDU_CIST_INT_PATH_COST_OFFSET);
+    ND_PRINT((ndo, "CIST int-root-pathcost %u,",
             EXTRACT_32BITS(ptr + MST_BPDU_CIST_INT_PATH_COST_OFFSET)));
 
+    ND_TCHECK_BRIDGE_ID(ptr + MST_BPDU_CIST_BRIDGE_ID_OFFSET);
     ND_PRINT((ndo, "\n\tCIST bridge-id %s, ",
            stp_print_bridge_id(ptr + MST_BPDU_CIST_BRIDGE_ID_OFFSET)));
 
+    ND_TCHECK(ptr[MST_BPDU_CIST_REMAIN_HOPS_OFFSET]);
     ND_PRINT((ndo, "CIST remaining-hops %d", ptr[MST_BPDU_CIST_REMAIN_HOPS_OFFSET]));
 
     /* Dump all MSTI's */
+    ND_TCHECK_16BITS(ptr + MST_BPDU_VER3_LEN_OFFSET);
     v3len = EXTRACT_16BITS(ptr + MST_BPDU_VER3_LEN_OFFSET);
     if (v3len > MST_BPDU_CONFIG_INFO_LENGTH) {
         len = v3len - MST_BPDU_CONFIG_INFO_LENGTH;
         offset = MST_BPDU_MSTI_OFFSET;
         while (len >= MST_BPDU_MSTI_LENGTH) {
+            ND_TCHECK2(*(ptr + offset), MST_BPDU_MSTI_LENGTH);
+
             msti = EXTRACT_16BITS(ptr + offset +
                                   MST_BPDU_MSTI_ROOT_PRIO_OFFSET);
             msti = msti & 0x0FFF;
@@ -314,9 +336,13 @@
             offset += MST_BPDU_MSTI_LENGTH;
         }
     }
+    return 1;
+
+trunc:
+    return 0;
 }
 
-static void
+static int
 stp_print_spb_bpdu(netdissect_options *ndo, const struct stp_bpdu_ *stp_bpdu,
                    u_int offset)
 {
@@ -326,13 +352,18 @@
      * in non-verbose mode don't print anything.
      */
     if (!ndo->ndo_vflag) {
-        return;
+        return 1;
     }
 
     ptr = (const u_char *)stp_bpdu;
-    ND_PRINT((ndo, "\n\tv4len %d AUXMCID Name %s, Rev %u, \n\t\tdigest %08x%08x%08x%08x",
-            EXTRACT_16BITS (ptr + offset),
-            ptr + offset + SPB_BPDU_CONFIG_NAME_OFFSET,
+    ND_TCHECK_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET + 16);
+
+    ND_PRINT((ndo, "\n\tv4len %d, ", EXTRACT_16BITS (ptr + offset)));
+    ND_PRINT((ndo, "AUXMCID Name "));
+    if (fn_printzp(ndo, ptr + offset + SPB_BPDU_CONFIG_NAME_OFFSET, 32,
+		   ndo->ndo_snapend))
+	goto trunc;
+    ND_PRINT((ndo, ", Rev %u,\n\t\tdigest %08x%08x%08x%08x",
             EXTRACT_16BITS(ptr + offset + SPB_BPDU_CONFIG_REV_OFFSET),
             EXTRACT_32BITS(ptr + offset + SPB_BPDU_CONFIG_DIGEST_OFFSET),
             EXTRACT_32BITS(ptr + offset + SPB_BPDU_CONFIG_DIGEST_OFFSET + 4),
@@ -340,8 +371,8 @@
             EXTRACT_32BITS(ptr + offset + SPB_BPDU_CONFIG_DIGEST_OFFSET + 12)));
 
     ND_PRINT((ndo, "\n\tAgreement num %d, Discarded Agreement num %d, Agreement valid-"
-            "flag %d, \n\tRestricted role-flag: %d, Format id %d cap %d, "
-            "Convention id %d cap %d, \n\tEdge count %d, "
+            "flag %d,\n\tRestricted role-flag: %d, Format id %d cap %d, "
+            "Convention id %d cap %d,\n\tEdge count %d, "
             "Agreement digest %08x%08x%08x%08x%08x\n",
             ptr[offset + SPB_BPDU_AGREEMENT_OFFSET]>>6,
             ptr[offset + SPB_BPDU_AGREEMENT_OFFSET]>>4 & 0x3,
@@ -353,10 +384,14 @@
             ptr[offset + SPB_BPDU_AGREEMENT_CON_OFFSET]&0x00ff,
             EXTRACT_16BITS(ptr + offset + SPB_BPDU_AGREEMENT_EDGE_OFFSET),
             EXTRACT_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET),
-            EXTRACT_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET)+4,
-            EXTRACT_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET)+8,
-            EXTRACT_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET)+12,
-            EXTRACT_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET)+16));
+            EXTRACT_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET+4),
+            EXTRACT_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET+8),
+            EXTRACT_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET+12),
+            EXTRACT_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET+16)));
+    return 1;
+
+trunc:
+    return 0;
 }
 
 /*
@@ -369,17 +404,19 @@
     u_int                  mstp_len;
     u_int                  spb_len;
 
-    stp_bpdu = (struct stp_bpdu_*)p;
+    stp_bpdu = (const struct stp_bpdu_*)p;
 
     /* Minimum STP Frame size. */
     if (length < 4)
         goto trunc;
 
+    ND_TCHECK(stp_bpdu->protocol_id);
     if (EXTRACT_16BITS(&stp_bpdu->protocol_id)) {
         ND_PRINT((ndo, "unknown STP version, length %u", length));
         return;
     }
 
+    ND_TCHECK(stp_bpdu->protocol_version);
     ND_PRINT((ndo, "STP %s", tok2str(stp_proto_values, "Unknown STP protocol (0x%02x)",
                          stp_bpdu->protocol_version)));
 
@@ -393,6 +430,7 @@
         return;
     }
 
+    ND_TCHECK(stp_bpdu->bpdu_type);
     ND_PRINT((ndo, ", %s", tok2str(stp_bpdu_type_values, "Unknown BPDU Type (0x%02x)",
                            stp_bpdu->bpdu_type)));
 
@@ -401,7 +439,8 @@
         if (length < sizeof(struct stp_bpdu_) - 1) {
             goto trunc;
         }
-        stp_print_config_bpdu(ndo, stp_bpdu, length);
+        if (!stp_print_config_bpdu(ndo, stp_bpdu, length))
+            goto trunc;
         break;
 
     case STP_BPDU_TYPE_RSTP:
@@ -409,25 +448,29 @@
             if (length < sizeof(struct stp_bpdu_)) {
                 goto trunc;
             }
-            stp_print_config_bpdu(ndo, stp_bpdu, length);
+            if (!stp_print_config_bpdu(ndo, stp_bpdu, length))
+                goto trunc;
         } else if (stp_bpdu->protocol_version == STP_PROTO_MSTP ||
                    stp_bpdu->protocol_version == STP_PROTO_SPB) {
             if (length < STP_BPDU_MSTP_MIN_LEN) {
                 goto trunc;
             }
 
+            ND_TCHECK(stp_bpdu->v1_length);
             if (stp_bpdu->v1_length != 0) {
                 /* FIX ME: Emit a message here ? */
                 goto trunc;
             }
 
             /* Validate v3 length */
+            ND_TCHECK_16BITS(p + MST_BPDU_VER3_LEN_OFFSET);
             mstp_len = EXTRACT_16BITS(p + MST_BPDU_VER3_LEN_OFFSET);
             mstp_len += 2;  /* length encoding itself is 2 bytes */
             if (length < (sizeof(struct stp_bpdu_) + mstp_len)) {
                 goto trunc;
             }
-            stp_print_mstp_bpdu(ndo, stp_bpdu, length);
+            if (!stp_print_mstp_bpdu(ndo, stp_bpdu, length))
+                goto trunc;
 
             if (stp_bpdu->protocol_version == STP_PROTO_SPB)
             {
@@ -438,7 +481,8 @@
                   spb_len < SPB_BPDU_MIN_LEN) {
                 goto trunc;
               }
-              stp_print_spb_bpdu(ndo, stp_bpdu, (sizeof(struct stp_bpdu_) + mstp_len));
+              if (!stp_print_spb_bpdu(ndo, stp_bpdu, (sizeof(struct stp_bpdu_) + mstp_len)))
+                goto trunc;
             }
         }
         break;
@@ -452,7 +496,7 @@
     }
 
     return;
- trunc:
+trunc:
     ND_PRINT((ndo, "[|stp %d]", length));
 }