net: recvmmsg: Strip MSG_WAITFORONE when calling recvmsg

recvmmsg fails on a raw socket with EINVAL. The reason for this is
packet_recvmsg checks the incoming flags:

        err = -EINVAL;
        if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
                goto out;

This patch strips out MSG_WAITFORONE when calling recvmmsg which
fixes the issue.

Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: stable@kernel.org [2.6.34+]
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 2 deletions

diff --git a/net/socket.c b/net/socket.c
index 310d16b1b3c9..65b2310a2cb2 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -2122,14 +2122,16 @@ int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
                  */
                 if (MSG_CMSG_COMPAT & flags) {
                         err = __sys_recvmsg(sock, (struct msghdr __user *)compat_entry,
-                                            &msg_sys, flags, datagrams);
+                                            &msg_sys, flags & ~MSG_WAITFORONE,
+                                            datagrams);
                         if (err < 0)
                                 break;
                         err = __put_user(err, &compat_entry->msg_len);
                         ++compat_entry;
                 } else {
                         err = __sys_recvmsg(sock, (struct msghdr __user *)entry,
-                                            &msg_sys, flags, datagrams);
+                                            &msg_sys, flags & ~MSG_WAITFORONE,
+                                            datagrams);
                         if (err < 0)
                                 break;
                         err = put_user(err, &entry->msg_len);