ping: fix incorrect handling of -I (Iouri Kharon <bc-info@styx.cabel.net>)

1 files changed, 8 insertions, 5 deletions

diff --git a/networking/ping.c b/networking/ping.c
index c4a498cd8..6945abb4a 100644
--- a/networking/ping.c
+++ b/networking/ping.c
@@ -530,8 +530,12 @@ static void ping4(len_and_sockaddr *lsa)
 
         pingsock = create_icmp_socket();
         pingaddr.sin = lsa->sin;
-        if (source_lsa)
-                xbind(pingsock, &lsa->sa, lsa->len);
+        if (source_lsa) {
+                if (setsockopt(pingsock, IPPROTO_IP, IP_MULTICAST_IF,
+                                &source_lsa->sa, source_lsa->len))
+                        bb_error_msg_and_die("can't set multicast source interface");
+                xbind(pingsock, &source_lsa->sa, source_lsa->len);
+        }
 
         /* enable broadcast pings */
         setsockopt_broadcast(pingsock);
@@ -578,7 +582,7 @@ static void ping6(len_and_sockaddr *lsa)
         pingaddr.sin6 = lsa->sin6;
         /* untested whether "-I addr" really works for IPv6: */
         if (source_lsa)
-                xbind(pingsock, &lsa->sa, lsa->len);
+                xbind(pingsock, &source_lsa->sa, source_lsa->len);
 
 #ifdef ICMP6_FILTER
         {
@@ -659,7 +663,7 @@ static void ping(len_and_sockaddr *lsa)
         printf("PING %s (%s)", hostname, dotted);
         if (source_lsa) {
                 printf(" from %s",
-                        xmalloc_sockaddr2dotted_noport(&lsa->sa, lsa->len));
+                        xmalloc_sockaddr2dotted_noport(&source_lsa->sa, source_lsa->len));
         }
         printf(": %d data bytes\n", datalen);
 
@@ -691,7 +695,6 @@ int ping_main(int argc, char **argv)
                 if_index = if_nametoindex(opt_I);
                 if (!if_index) {
                         /* TODO: I'm not sure it takes IPv6 unless in [XX:XX..] format */
-                        /* (ping doesn't support source IPv6 addresses yet anyway) */
                         source_lsa = xdotted2sockaddr(opt_I, 0);
                 }
         }