Fix truncated pings results when packets are too small. Also check for packet maximum...

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@6443 3c298f89-4303-0410-b956-a3cf2f4a3e73

diff --git a/package/busybox/patches/450-truncated_ping_results.patch b/package/busybox/patches/450-truncated_ping_results.patch
new file mode 100644 (file)
index 0000000..30e8670
--- /dev/null
+++ b/package/busybox/patches/450-truncated_ping_results.patch
@@ -0,0 +1,42 @@
+--- busybox-1.4.1/networking/ping.c    2007-01-24 22:34:34.000000000 +0100
++++ busybox-1.4.1.new/networking/ping.c        2007-02-28 20:35:59.000000000 +0100
+@@ -70,7 +70,7 @@
+       struct sockaddr_in pingaddr;
+       struct icmp *pkt;
+       int pingsock, c;
+-      char packet[DEFDATALEN + MAXIPLEN + MAXICMPLEN];
++      char packet[datalen + MAXIPLEN + MAXICMPLEN];
+ 
+       pingsock = create_icmp_socket();
+ 
+@@ -86,7 +86,7 @@
+       pkt->icmp_type = ICMP_ECHO;
+       pkt->icmp_cksum = in_cksum((unsigned short *) pkt, sizeof(packet));
+ 
+-      c = sendto(pingsock, packet, DEFDATALEN + ICMP_MINLEN, 0,
++      c = sendto(pingsock, packet, datalen + ICMP_MINLEN, 0,
+                          (struct sockaddr *) &pingaddr, sizeof(struct sockaddr_in));
+ 
+       if (c < 0) {
+@@ -257,8 +257,8 @@
+ 
+       gettimeofday(&tv, NULL);
+ 
+-      /* discard if too short */
+-      if (sz < (datalen + ICMP_MINLEN))
++      /* discard if too short / long */
++      if (sz < (datalen + ICMP_MINLEN) || sz > (MAXICMPLEN))
+               return;
+ 
+       /* check IP header */
+@@ -274,6 +274,10 @@
+               ++nreceived;
+               tp = (struct timeval *) icmppkt->icmp_data;
+ 
++              /* If packet is too short, results will be truncated */
++              if (sz < (ICMP_MINLEN + sizeof(tv.tv_sec) + sizeof(tv.tv_usec)))
++                      return;
++
+               if ((tv.tv_usec -= tp->tv_usec) < 0) {
+                       --tv.tv_sec;
+                       tv.tv_usec += 1000000;