CVE-2017-13006/L2TP: Check whether an AVP's content exceeds the AVP length.

It's not good enough to check whether all the data specified by the AVP
length was captured - you also have to check whether that length is
large enough for all the required data in the AVP.

This fixes a buffer over-read discovered by Yannick Formaggio.

Add a test using the capture file supplied by the reporter(s).

diff --git a/print-l2tp.c b/print-l2tp.c
index 42ae39107372188f368885c992f063f31d596c9a..d70d434f7a5af8a16830c4f5a2b703ae8227880b 100644 (file)
--- a/print-l2tp.c
+++ b/print-l2tp.c
@@ -297,10 +297,14 @@ print_32bits_val(netdissect_options *ndo, const uint32_t *dat)
 /* AVP-specific print out routines */
 /***********************************/
 static void
-l2tp_msgtype_print(netdissect_options *ndo, const u_char *dat)
+l2tp_msgtype_print(netdissect_options *ndo, const u_char *dat, u_int length)
 {
        const uint16_t *ptr = (const uint16_t *)dat;
 
+       if (length < 2) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
        ND_PRINT((ndo, "%s", tok2str(l2tp_msgtype2str, "MSGTYPE-#%u",
            EXTRACT_16BITS(ptr))));
 }
@@ -310,28 +314,53 @@ l2tp_result_code_print(netdissect_options *ndo, const u_char *dat, u_int length)
 {
        const uint16_t *ptr = (const uint16_t *)dat;
 
-       ND_PRINT((ndo, "%u", EXTRACT_16BITS(ptr))); ptr++;      /* Result Code */
-       if (length > 2) {                               /* Error Code (opt) */
-               ND_PRINT((ndo, "/%u", EXTRACT_16BITS(ptr))); ptr++;
+       /* Result Code */
+       if (length < 2) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
        }
-       if (length > 4) {                               /* Error Message (opt) */
-               ND_PRINT((ndo, " "));
-               print_string(ndo, (const u_char *)ptr, length - 4);
+       ND_PRINT((ndo, "%u", EXTRACT_16BITS(ptr)));
+       ptr++;
+       length -= 2;
+
+       /* Error Code (opt) */
+       if (length == 0)
+               return;
+       if (length < 2) {
+               ND_PRINT((ndo, " AVP too short"));
+               return;
        }
+       ND_PRINT((ndo, "/%u", EXTRACT_16BITS(ptr)));
+       ptr++;
+       length -= 2;
+
+       /* Error Message (opt) */
+       if (length == 0)
+               return;
+       ND_PRINT((ndo, " "));
+       print_string(ndo, (const u_char *)ptr, length);
 }
 
 static void
-l2tp_proto_ver_print(netdissect_options *ndo, const uint16_t *dat)
+l2tp_proto_ver_print(netdissect_options *ndo, const uint16_t *dat, u_int length)
 {
+       if (length < 2) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
        ND_PRINT((ndo, "%u.%u", (EXTRACT_16BITS(dat) >> 8),
            (EXTRACT_16BITS(dat) & 0xff)));
 }
 
 static void
-l2tp_framing_cap_print(netdissect_options *ndo, const u_char *dat)
+l2tp_framing_cap_print(netdissect_options *ndo, const u_char *dat, u_int length)
 {
        const uint32_t *ptr = (const uint32_t *)dat;
 
+       if (length < 4) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
        if (EXTRACT_32BITS(ptr) &  L2TP_FRAMING_CAP_ASYNC_MASK) {
                ND_PRINT((ndo, "A"));
        }
@@ -341,10 +370,14 @@ l2tp_framing_cap_print(netdissect_options *ndo, const u_char *dat)
 }
 
 static void
-l2tp_bearer_cap_print(netdissect_options *ndo, const u_char *dat)
+l2tp_bearer_cap_print(netdissect_options *ndo, const u_char *dat, u_int length)
 {
        const uint32_t *ptr = (const uint32_t *)dat;
 
+       if (length < 4) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
        if (EXTRACT_32BITS(ptr) &  L2TP_BEARER_CAP_ANALOG_MASK) {
                ND_PRINT((ndo, "A"));
        }
@@ -356,19 +389,29 @@ l2tp_bearer_cap_print(netdissect_options *ndo, const u_char *dat)
 static void
 l2tp_q931_cc_print(netdissect_options *ndo, const u_char *dat, u_int length)
 {
+       if (length < 3) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
        print_16bits_val(ndo, (const uint16_t *)dat);
        ND_PRINT((ndo, ", %02x", dat[2]));
-       if (length > 3) {
+       dat += 3;
+       length -= 3;
+       if (length != 0) {
                ND_PRINT((ndo, " "));
-               print_string(ndo, dat+3, length-3);
+               print_string(ndo, dat, length);
        }
 }
 
 static void
-l2tp_bearer_type_print(netdissect_options *ndo, const u_char *dat)
+l2tp_bearer_type_print(netdissect_options *ndo, const u_char *dat, u_int length)
 {
        const uint32_t *ptr = (const uint32_t *)dat;
 
+       if (length < 4) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
        if (EXTRACT_32BITS(ptr) &  L2TP_BEARER_TYPE_ANALOG_MASK) {
                ND_PRINT((ndo, "A"));
        }
@@ -378,10 +421,14 @@ l2tp_bearer_type_print(netdissect_options *ndo, const u_char *dat)
 }
 
 static void
-l2tp_framing_type_print(netdissect_options *ndo, const u_char *dat)
+l2tp_framing_type_print(netdissect_options *ndo, const u_char *dat, u_int length)
 {
        const uint32_t *ptr = (const uint32_t *)dat;
 
+       if (length < 4) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
        if (EXTRACT_32BITS(ptr) &  L2TP_FRAMING_TYPE_ASYNC_MASK) {
                ND_PRINT((ndo, "A"));
        }
@@ -397,67 +444,117 @@ l2tp_packet_proc_delay_print(netdissect_options *ndo)
 }
 
 static void
-l2tp_proxy_auth_type_print(netdissect_options *ndo, const u_char *dat)
+l2tp_proxy_auth_type_print(netdissect_options *ndo, const u_char *dat, u_int length)
 {
        const uint16_t *ptr = (const uint16_t *)dat;
 
+       if (length < 2) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
        ND_PRINT((ndo, "%s", tok2str(l2tp_authentype2str,
                             "AuthType-#%u", EXTRACT_16BITS(ptr))));
 }
 
 static void
-l2tp_proxy_auth_id_print(netdissect_options *ndo, const u_char *dat)
+l2tp_proxy_auth_id_print(netdissect_options *ndo, const u_char *dat, u_int length)
 {
        const uint16_t *ptr = (const uint16_t *)dat;
 
+       if (length < 2) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
        ND_PRINT((ndo, "%u", EXTRACT_16BITS(ptr) & L2TP_PROXY_AUTH_ID_MASK));
 }
 
 static void
-l2tp_call_errors_print(netdissect_options *ndo, const u_char *dat)
+l2tp_call_errors_print(netdissect_options *ndo, const u_char *dat, u_int length)
 {
        const uint16_t *ptr = (const uint16_t *)dat;
        uint16_t val_h, val_l;
 
+       if (length < 2) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
        ptr++;          /* skip "Reserved" */
+       length -= 2;
 
-       val_h = EXTRACT_16BITS(ptr); ptr++;
-       val_l = EXTRACT_16BITS(ptr); ptr++;
+       if (length < 4) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
+       val_h = EXTRACT_16BITS(ptr); ptr++; length -= 2;
+       val_l = EXTRACT_16BITS(ptr); ptr++; length -= 2;
        ND_PRINT((ndo, "CRCErr=%u ", (val_h<<16) + val_l));
 
-       val_h = EXTRACT_16BITS(ptr); ptr++;
-       val_l = EXTRACT_16BITS(ptr); ptr++;
+       if (length < 4) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
+       val_h = EXTRACT_16BITS(ptr); ptr++; length -= 2;
+       val_l = EXTRACT_16BITS(ptr); ptr++; length -= 2;
        ND_PRINT((ndo, "FrameErr=%u ", (val_h<<16) + val_l));
 
-       val_h = EXTRACT_16BITS(ptr); ptr++;
-       val_l = EXTRACT_16BITS(ptr); ptr++;
+       if (length < 4) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
+       val_h = EXTRACT_16BITS(ptr); ptr++; length -= 2;
+       val_l = EXTRACT_16BITS(ptr); ptr++; length -= 2;
        ND_PRINT((ndo, "HardOver=%u ", (val_h<<16) + val_l));
 
-       val_h = EXTRACT_16BITS(ptr); ptr++;
-       val_l = EXTRACT_16BITS(ptr); ptr++;
+       if (length < 4) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
+       val_h = EXTRACT_16BITS(ptr); ptr++; length -= 2;
+       val_l = EXTRACT_16BITS(ptr); ptr++; length -= 2;
        ND_PRINT((ndo, "BufOver=%u ", (val_h<<16) + val_l));
 
-       val_h = EXTRACT_16BITS(ptr); ptr++;
-       val_l = EXTRACT_16BITS(ptr); ptr++;
+       if (length < 4) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
+       val_h = EXTRACT_16BITS(ptr); ptr++; length -= 2;
+       val_l = EXTRACT_16BITS(ptr); ptr++; length -= 2;
        ND_PRINT((ndo, "Timeout=%u ", (val_h<<16) + val_l));
 
+       if (length < 4) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
        val_h = EXTRACT_16BITS(ptr); ptr++;
        val_l = EXTRACT_16BITS(ptr); ptr++;
        ND_PRINT((ndo, "AlignErr=%u ", (val_h<<16) + val_l));
 }
 
 static void
-l2tp_accm_print(netdissect_options *ndo, const u_char *dat)
+l2tp_accm_print(netdissect_options *ndo, const u_char *dat, u_int length)
 {
        const uint16_t *ptr = (const uint16_t *)dat;
        uint16_t val_h, val_l;
 
+       if (length < 2) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
        ptr++;          /* skip "Reserved" */
+       length -= 2;
 
-       val_h = EXTRACT_16BITS(ptr); ptr++;
-       val_l = EXTRACT_16BITS(ptr); ptr++;
+       if (length < 4) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
+       val_h = EXTRACT_16BITS(ptr); ptr++; length -= 2;
+       val_l = EXTRACT_16BITS(ptr); ptr++; length -= 2;
        ND_PRINT((ndo, "send=%08x ", (val_h<<16) + val_l));
 
+       if (length < 4) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
        val_h = EXTRACT_16BITS(ptr); ptr++;
        val_l = EXTRACT_16BITS(ptr); ptr++;
        ND_PRINT((ndo, "recv=%08x ", (val_h<<16) + val_l));
@@ -468,14 +565,27 @@ l2tp_ppp_discon_cc_print(netdissect_options *ndo, const u_char *dat, u_int lengt
 {
        const uint16_t *ptr = (const uint16_t *)dat;
 
-       ND_PRINT((ndo, "%04x, ", EXTRACT_16BITS(ptr))); ptr++;  /* Disconnect Code */
-       ND_PRINT((ndo, "%04x ",  EXTRACT_16BITS(ptr))); ptr++;  /* Control Protocol Number */
+       if (length < 5) {
+               ND_PRINT((ndo, "AVP too short"));
+               return;
+       }
+       /* Disconnect Code */
+       ND_PRINT((ndo, "%04x, ", EXTRACT_16BITS(dat)));
+       dat += 2;
+       length -= 2;
+       /* Control Protocol Number */
+       ND_PRINT((ndo, "%04x ",  EXTRACT_16BITS(dat)));
+       dat += 2;
+       length -= 2;
+       /* Direction */
        ND_PRINT((ndo, "%s", tok2str(l2tp_cc_direction2str,
-                            "Direction-#%u", *((const u_char *)ptr++))));
+                            "Direction-#%u", EXTRACT_8BITS(ptr))));
+       ptr++;
+       length--;
 
-       if (length > 5) {
+       if (length != 0) {
                ND_PRINT((ndo, " "));
-               print_string(ndo, (const u_char *)ptr, length-5);
+               print_string(ndo, (const u_char *)ptr, length);
        }
 }
 
@@ -508,7 +618,12 @@ l2tp_avp_print(netdissect_options *ndo, const u_char *dat, int length)
        /* If it goes past the end of the remaining length of the captured
           data, we'll give up. */
        ND_TCHECK2(*ptr, len);
-       /* After this point, no need to worry about truncation */
+
+       /*
+        * After this point, we don't need to check whether we go past
+        * the length of the captured data; however, we *do* need to
+        * check whether we go past the end of the AVP.
+        */
 
        if (EXTRACT_16BITS(ptr) & L2TP_AVP_HDR_FLAG_MANDATORY) {
                ND_PRINT((ndo, "*"));
@@ -537,27 +652,35 @@ l2tp_avp_print(netdissect_options *ndo, const u_char *dat, int length)
                } else {
                        switch (attr_type) {
                        case L2TP_AVP_MSGTYPE:
-                               l2tp_msgtype_print(ndo, (const u_char *)ptr);
+                               l2tp_msgtype_print(ndo, (const u_char *)ptr, len-6);
                                break;
                        case L2TP_AVP_RESULT_CODE:
                                l2tp_result_code_print(ndo, (const u_char *)ptr, len-6);
                                break;
                        case L2TP_AVP_PROTO_VER:
-                               l2tp_proto_ver_print(ndo, ptr);
+                               l2tp_proto_ver_print(ndo, ptr, len-6);
                                break;
                        case L2TP_AVP_FRAMING_CAP:
-                               l2tp_framing_cap_print(ndo, (const u_char *)ptr);
+                               l2tp_framing_cap_print(ndo, (const u_char *)ptr, len-6);
                                break;
                        case L2TP_AVP_BEARER_CAP:
-                               l2tp_bearer_cap_print(ndo, (const u_char *)ptr);
+                               l2tp_bearer_cap_print(ndo, (const u_char *)ptr, len-6);
                                break;
                        case L2TP_AVP_TIE_BREAKER:
+                               if (len-6 < 8) {
+                                       ND_PRINT((ndo, "AVP too short"));
+                                       break;
+                               }
                                print_octets(ndo, (const u_char *)ptr, 8);
                                break;
                        case L2TP_AVP_FIRM_VER:
                        case L2TP_AVP_ASSND_TUN_ID:
                        case L2TP_AVP_RECV_WIN_SIZE:
                        case L2TP_AVP_ASSND_SESS_ID:
+                               if (len-6 < 2) {
+                                       ND_PRINT((ndo, "AVP too short"));
+                                       break;
+                               }
                                print_16bits_val(ndo, ptr);
                                break;
                        case L2TP_AVP_HOST_NAME:
@@ -582,6 +705,10 @@ l2tp_avp_print(netdissect_options *ndo, const u_char *dat, int length)
                                l2tp_q931_cc_print(ndo, (const u_char *)ptr, len-6);
                                break;
                        case L2TP_AVP_CHALLENGE_RESP:
+                               if (len-6 < 16) {
+                                       ND_PRINT((ndo, "AVP too short"));
+                                       break;
+                               }
                                print_octets(ndo, (const u_char *)ptr, 16);
                                break;
                        case L2TP_AVP_CALL_SER_NUM:
@@ -590,28 +717,32 @@ l2tp_avp_print(netdissect_options *ndo, const u_char *dat, int length)
                        case L2TP_AVP_TX_CONN_SPEED:
                        case L2TP_AVP_PHY_CHANNEL_ID:
                        case L2TP_AVP_RX_CONN_SPEED:
+                               if (len-6 < 4) {
+                                       ND_PRINT((ndo, "AVP too short"));
+                                       break;
+                               }
                                print_32bits_val(ndo, (const uint32_t *)ptr);
                                break;
                        case L2TP_AVP_BEARER_TYPE:
-                               l2tp_bearer_type_print(ndo, (const u_char *)ptr);
+                               l2tp_bearer_type_print(ndo, (const u_char *)ptr, len-6);
                                break;
                        case L2TP_AVP_FRAMING_TYPE:
-                               l2tp_framing_type_print(ndo, (const u_char *)ptr);
+                               l2tp_framing_type_print(ndo, (const u_char *)ptr, len-6);
                                break;
                        case L2TP_AVP_PACKET_PROC_DELAY:
                                l2tp_packet_proc_delay_print(ndo);
                                break;
                        case L2TP_AVP_PROXY_AUTH_TYPE:
-                               l2tp_proxy_auth_type_print(ndo, (const u_char *)ptr);
+                               l2tp_proxy_auth_type_print(ndo, (const u_char *)ptr, len-6);
                                break;
                        case L2TP_AVP_PROXY_AUTH_ID:
-                               l2tp_proxy_auth_id_print(ndo, (const u_char *)ptr);
+                               l2tp_proxy_auth_id_print(ndo, (const u_char *)ptr, len-6);
                                break;
                        case L2TP_AVP_CALL_ERRORS:
-                               l2tp_call_errors_print(ndo, (const u_char *)ptr);
+                               l2tp_call_errors_print(ndo, (const u_char *)ptr, len-6);
                                break;
                        case L2TP_AVP_ACCM:
-                               l2tp_accm_print(ndo, (const u_char *)ptr);
+                               l2tp_accm_print(ndo, (const u_char *)ptr, len-6);
                                break;
                        case L2TP_AVP_SEQ_REQUIRED:
                                break;  /* No Attribute Value */

diff --git a/tests/TESTLIST b/tests/TESTLIST
index 8ae6109955327e4f3be3dc6376778db25faff9d8..f9ae40dda945bc0d53dbd672400938d5c2e9cc3c 100644 (file)
--- a/tests/TESTLIST
+++ b/tests/TESTLIST
@@ -500,6 +500,9 @@ lmpv1_busyloop              lmpv1_busyloop.pcap             lmpv1_busyloop.out      -vvv -e
 juniper_atm1           juniper_atm1.pcap               juniper_atm1.out        -vvv -e
 juniper_es             juniper_es.pcap                 juniper_es.out  -vvv -e
 
+# bad packets from Yannick Formaggio
+l2tp-avp-overflow      l2tp-avp-overflow.pcap          l2tp-avp-overflow.out   -v
+
 # RTP tests
 # fuzzed pcap
 rtp-seg-fault-1  rtp-seg-fault-1.pcap  rtp-seg-fault-1.out  -v -T rtp

diff --git a/tests/l2tp-avp-overflow.out b/tests/l2tp-avp-overflow.out
new file mode 100644 (file)
index 0000000..a3b1db2
--- /dev/null
+++ b/tests/l2tp-avp-overflow.out
@@ -0,0 +1,39 @@
+IP (tos 0x30, ttl 48, id 12331, offset 0, flags [none], proto UDP (17), length 12336, bad cksum 1f51 (->ab7b)!)
+    127.0.0.229.12416 > 127.0.128.1.1701:  l2tp:[TL](560/2056) AVP-#60963() |...
+IP (tos 0x30, ttl 48, id 12336, offset 0, flags [none], proto UDP (17), length 12336, bad cksum 1f51 (->2a8b)!)
+    127.0.0.229.12416 > 127.236.0.1.1701:  l2tp:[TL](560/2056) AVP-#48() |...
+IP (tos 0x30, ttl 48, id 12331, offset 0, flags [none], proto UDP (17), length 8752, bad cksum 1f51 (->3890)!)
+    127.0.0.229.32767 > 127.236.0.1.1701:  l2tp:[TL](560/2056) ACCM(AVP too short) |...
+IP (tos 0x30, ttl 48, id 12336, offset 0, flags [none], proto UDP (17), length 12336, bad cksum 1f51 (->2a8b)!)
+    127.0.0.229.12416 > 127.236.0.1.1701:  l2tp:[TL](560/2056) ACCM(AVP too short) |...
+IP (tos 0x30, ttl 48, id 12331, offset 0, flags [none], proto UDP (17), length 12336, bad cksum 1f51 (->2a90)!)
+    127.0.0.229.12416 > 127.236.0.1.1701:  l2tp:[TL](560/2056) ACCM(AVP too short) |...
+IP (tos 0x30, ttl 48, id 12336, offset 0, flags [none], proto UDP (17), length 12336, bad cksum 1f51 (->ab5d)!)
+    127.0.0.0.0 > 0.0.0.0.2048: UDP, bad length 17704 > 12308
+[|ether]
+IP (tos 0x30, ttl 48, id 12336, offset 0, flags [none], proto UDP (17), length 12336, bad cksum 1f51 (->2a8b)!)
+    127.0.0.229.12416 > 127.236.0.1.1701:  l2tp:[TL](560/2056) AVP-#48() |...
+IP (tos 0x30, ttl 48, id 12331, offset 0, flags [none], proto UDP (17), length 8752, bad cksum 1f51 (->3890)!)
+    127.0.0.229.12416 > 127.236.0.1.1701:  l2tp:[TL](560/2056) ACCM(AVP too short) |...
+IP (tos 0x30, ttl 48, id 12336, offset 0, flags [none], proto UDP (17), length 12336, bad cksum 1f51 (->2a8b)!)
+    127.0.0.229.12416 > 127.236.0.1.1701:  l2tp:[TL](560/2056) ACCM(AVP too short) |...
+IP (tos 0x30, ttl 48, id 12331, offset 0, flags [none], proto UDP (17), length 12336, bad cksum 1f51 (->2a90)!)
+    127.0.0.229.12416 > 127.236.0.1.1701:  l2tp:[TL](560/2056) ACCM(AVP too short) |...
+IP (tos 0x30, ttl 48, id 12336, offset 0, flags [none], proto UDP (17), length 12336, bad cksum 1f51 (->ab5d)!)
+    127.0.0.0.0 > 0.0.0.0.2048: UDP, bad length 17704 > 12308
+[|ether]
+IP (tos 0x30, ttl 48, id 12336, offset 0, flags [none], proto UDP (17), length 12336, bad cksum 1f51 (->2a8b)!)
+    127.0.0.229.12416 > 127.236.0.1.1701:  l2tp:[TL](560/2056) AVP-#48() |...
+IP (tos 0x30, ttl 48, id 12331, offset 0, flags [none], proto UDP (17), length 8752, bad cksum 1f51 (->3890)!)
+    127.0.0.229.12416 > 127.236.0.1.1701:  l2tp:[TL](560/2056) ACCM(AVP too short) |...
+IP (tos 0x30, ttl 48, id 12336, offset 0, flags [none], proto UDP (17), length 12336, bad cksum 1f51 (->2a8b)!)
+    127.0.0.229.12416 > 127.236.0.1.1701:  l2tp:[TL](560/2056) ACCM(AVP too short) |...
+IP (tos 0x30, ttl 48, id 12331, offset 0, flags [none], proto UDP (17), length 12336, bad cksum 1f51 (->2a90)!)
+    127.0.0.229.12416 > 127.236.0.1.1701:  l2tp:[TL](560/2056) ACCM(AVP too short) |...
+IP (tos 0x30, ttl 48, id 12336, offset 0, flags [none], proto UDP (17), length 12336, bad cksum 1f51 (->2a8b)!)
+    127.0.0.229.12416 > 127.236.0.1.1701:  l2tp:[TL](560/2056) AVP-#48() |...
+IP (tos 0x30, ttl 48, id 12331, offset 0, flags [none], proto UDP (17), length 8752, bad cksum 1f51 (->3890)!)
+    127.0.0.229.12416 > 127.236.0.1.1701:  l2tp:[TL](560/2056) VENDOR0001:ATTR0023(0530) |...
+IP (tos 0x30, ttl 48, id 12336, offset 0, flags [none], proto UDP (17), length 12336, bad cksum 1f51 (->2a8b)!)
+    127.0.0.229.12416 > 127.236.0.1.1701:  l2tp:[TL](560/2056) VENDOR0080:ATTR06a5(19e8) |...
+EXIT CODE 00000100

diff --git a/tests/l2tp-avp-overflow.pcap b/tests/l2tp-avp-overflow.pcap
new file mode 100644 (file)
index 0000000..5a6c406
Binary files /dev/null and b/tests/l2tp-avp-overflow.pcap differ