- don't free user-supplied string (via -e)

[oweals/busybox.git] / libbb / udp_io.c

diff --git a/libbb/udp_io.c b/libbb/udp_io.c
index 689c39a828edb39a48d5635e858a02f004e0f8cf..b31f28416b6031cd91b372603bd870b14ac8c6a5 100644 (file)
--- a/libbb/udp_io.c
+++ b/libbb/udp_io.c
@@ -13,7 +13,7 @@
  * This asks kernel to let us know dst addr/port of incoming packets
  * We don't check for errors here. Not supported == won't be used
  */
-void
+void FAST_FUNC
 socket_want_pktinfo(int fd)
 {
 #ifdef IP_PKTINFO
@@ -25,7 +25,7 @@ socket_want_pktinfo(int fd)
 }
 
 
-ssize_t
+ssize_t FAST_FUNC
 send_to_from(int fd, void *buf, size_t len, int flags,
                const struct sockaddr *to,
                const struct sockaddr *from,
@@ -36,11 +36,12 @@ send_to_from(int fd, void *buf, size_t len, int flags,
 #else
        struct iovec iov[1];
        struct msghdr msg;
-       char cbuf[sizeof(struct in_pktinfo)
+       union {
+               char cmsg[CMSG_SPACE(sizeof(struct in_pktinfo))];
 #if ENABLE_FEATURE_IPV6 && defined(IPV6_PKTINFO)
-               | sizeof(struct in6_pktinfo) /* (a|b) is poor man's max(a,b) */
+               char cmsg6[CMSG_SPACE(sizeof(struct in6_pktinfo))];
 #endif
-       ];
+       } u;
        struct cmsghdr* cmsgptr;
 
        if (from->sa_family != AF_INET
@@ -57,15 +58,15 @@ send_to_from(int fd, void *buf, size_t len, int flags,
        iov[0].iov_base = buf;
        iov[0].iov_len = len;
 
-       memset(cbuf, 0, sizeof(cbuf));
+       memset(&u, 0, sizeof(u));
 
        memset(&msg, 0, sizeof(msg));
        msg.msg_name = (void *)(struct sockaddr *)to; /* or compiler will annoy us */
        msg.msg_namelen = tolen;
        msg.msg_iov = iov;
        msg.msg_iovlen = 1;
-       msg.msg_control = cbuf;
-       msg.msg_controllen = sizeof(cbuf);
+       msg.msg_control = &u;
+       msg.msg_controllen = sizeof(u);
        msg.msg_flags = flags;
 
        cmsgptr = CMSG_FIRSTHDR(&msg);
@@ -89,6 +90,8 @@ send_to_from(int fd, void *buf, size_t len, int flags,
                pktptr->ipi6_addr = ((struct sockaddr_in6*)from)->sin6_addr;
        }
 #endif
+       msg.msg_controllen = cmsgptr->cmsg_len;
+
        return sendmsg(fd, &msg, flags);
 #endif
 }
@@ -97,7 +100,7 @@ send_to_from(int fd, void *buf, size_t len, int flags,
  * _Only_ IP/IPv6 address part of 'to' is _maybe_ modified.
  * Typical usage is to preinit 'to' with "default" value
  * before calling recv_from_to(). */
-ssize_t
+ssize_t FAST_FUNC
 recv_from_to(int fd, void *buf, size_t len, int flags,
                struct sockaddr *from, struct sockaddr *to,
                socklen_t sa_size)
@@ -109,7 +112,9 @@ recv_from_to(int fd, void *buf, size_t len, int flags,
        struct iovec iov[1];
        union {
                char cmsg[CMSG_SPACE(sizeof(struct in_pktinfo))];
+#if ENABLE_FEATURE_IPV6 && defined(IPV6_PKTINFO)
                char cmsg6[CMSG_SPACE(sizeof(struct in6_pktinfo))];
+#endif
        } u;
        struct cmsghdr *cmsgptr;
        struct msghdr msg;