udhcp[cd]: fix binding to network aliases. Closes 5432, 5438

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 9 insertions, 1 deletions

diff --git a/networking/udhcp/socket.c b/networking/udhcp/socket.c
index a5220ba74..a42106960 100644
--- a/networking/udhcp/socket.c
+++ b/networking/udhcp/socket.c
@@ -80,6 +80,7 @@ int FAST_FUNC udhcp_listen_socket(/*uint32_t ip,*/ int port, const char *inf)
 {
         int fd;
         struct sockaddr_in addr;
+        char *colon;
 
         log1("Opening listen socket on *:%d %s", port, inf);
         fd = xsocket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
@@ -88,10 +89,17 @@ int FAST_FUNC udhcp_listen_socket(/*uint32_t ip,*/ int port, const char *inf)
         if (setsockopt_broadcast(fd) == -1)
                 bb_perror_msg_and_die("SO_BROADCAST");
 
-        /* NB: bug 1032 says this doesn't work on ethernet aliases (ethN:M) */
+        /* SO_BINDTODEVICE doesn't work on ethernet aliases (ethN:M) */
+        colon = strrchr(inf, ':');
+        if (colon)
+                *colon = '\0';
+
         if (setsockopt_bindtodevice(fd, inf))
                 xfunc_die(); /* warning is already printed */
 
+        if (colon)
+                *colon = ':';
+
         memset(&addr, 0, sizeof(addr));
         addr.sin_family = AF_INET;
         addr.sin_port = htons(port);