releases/2.6.38.8/net-recvmmsg-strip-msg_waitforone-when-calling-recvmsg.patch

   1 From b9eb8b8752804cecbacdb4d24b52e823cf07f107 Mon Sep 17 00:00:00 2001
   2 From: Anton Blanchard <anton@samba.org>
   3 Date: Tue, 17 May 2011 15:38:57 -0400
   4 Subject: net: recvmmsg: Strip MSG_WAITFORONE when calling recvmsg
   5
   6 From: Anton Blanchard <anton@samba.org>
   7
   8 commit b9eb8b8752804cecbacdb4d24b52e823cf07f107 upstream.
   9
  10 recvmmsg fails on a raw socket with EINVAL. The reason for this is
  11 packet_recvmsg checks the incoming flags:
  12
  13         err = -EINVAL;
  14         if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
  15                 goto out;
  16
  17 This patch strips out MSG_WAITFORONE when calling recvmmsg which
  18 fixes the issue.
  19
  20 Signed-off-by: Anton Blanchard <anton@samba.org>
  21 Signed-off-by: David S. Miller <davem@davemloft.net>
  22 Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
  23
  24 ---
  25  net/socket.c |    6 ++++--
  26  1 file changed, 4 insertions(+), 2 deletions(-)
  27
  28 --- a/net/socket.c
  29 +++ b/net/socket.c
  30 @@ -2117,14 +2117,16 @@ int __sys_recvmmsg(int fd, struct mmsghd
  31                  */
  32                 if (MSG_CMSG_COMPAT & flags) {
  33                         err = __sys_recvmsg(sock, (struct msghdr __user *)compat_entry,
  34 -                                           &msg_sys, flags, datagrams);
  35 +                                           &msg_sys, flags & ~MSG_WAITFORONE,
  36 +                                           datagrams);
  37                         if (err < 0)
  38                                 break;
  39                         err = __put_user(err, &compat_entry->msg_len);
  40                         ++compat_entry;
  41                 } else {
  42                         err = __sys_recvmsg(sock, (struct msghdr __user *)entry,
  43 -                                           &msg_sys, flags, datagrams);
  44 +                                           &msg_sys, flags & ~MSG_WAITFORONE,
  45 +                                           datagrams);
  46                         if (err < 0)
  47                                 break;
  48                         err = put_user(err, &entry->msg_len);