package/utils/busybox/patches/002-libbb-send_to_from-do-not-require-that-to-should-hav.patch

   1 From 7cef4817d6d6d61a1166ed7dfc13537b95c65970 Mon Sep 17 00:00:00 2001
   2 From: Denys Vlasenko <vda.linux@googlemail.com>
   3 Date: Thu, 15 Sep 2016 13:20:51 +0200
   4 Subject: [PATCH] libbb:/send_to_from: do not require that "to" should have the
   5  same AF. Closes 9146
   6
   7 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
   8 ---
   9  libbb/udp_io.c | 10 ++++++++--
  10  1 file changed, 8 insertions(+), 2 deletions(-)
  11
  12 --- a/libbb/udp_io.c
  13 +++ b/libbb/udp_io.c
  14 @@ -70,7 +70,13 @@ send_to_from(int fd, void *buf, size_t l
  15         msg.msg_flags = flags;
  16
  17         cmsgptr = CMSG_FIRSTHDR(&msg);
  18 -       if (to->sa_family == AF_INET && from->sa_family == AF_INET) {
  19 +       /*
  20 +        * Users report that to->sa_family can be AF_INET6 too,
  21 +        * if "to" was acquired by recv_from_to(). IOW: recv_from_to()
  22 +        * was seen showing IPv6 "from" even when the destination
  23 +        * of received packet (our local address) was IPv4.
  24 +        */
  25 +       if (/* to->sa_family == AF_INET && */ from->sa_family == AF_INET) {
  26                 struct in_pktinfo *pktptr;
  27                 cmsgptr->cmsg_level = IPPROTO_IP;
  28                 cmsgptr->cmsg_type = IP_PKTINFO;
  29 @@ -86,7 +92,7 @@ send_to_from(int fd, void *buf, size_t l
  30                 pktptr->ipi_spec_dst = ((struct sockaddr_in*)from)->sin_addr;
  31         }
  32  # if ENABLE_FEATURE_IPV6 && defined(IPV6_PKTINFO)
  33 -       else if (to->sa_family == AF_INET6 && from->sa_family == AF_INET6) {
  34 +       else if (/* to->sa_family == AF_INET6 && */ from->sa_family == AF_INET6) {
  35                 struct in6_pktinfo *pktptr;
  36                 cmsgptr->cmsg_level = IPPROTO_IPV6;
  37                 cmsgptr->cmsg_type = IPV6_PKTINFO;