[NET]: Make sure ctl buffer is aligned properly in sys_sendmsg().

It's on the stack and declared as "unsigned char[]", but pointers
and similar can be in here thus we need to give it an explicit
alignment attribute.
Signed-off-by: NAlex Williamson <alex.williamson@hp.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/socket.c

@@ -1700,7 +1700,9 @@ asmlinkage long sys_sendmsg(int fd, struct msghdr __user *msg, unsigned flags)
 	struct socket *sock;
 	char address[MAX_SOCK_ADDR];
 	struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
-	unsigned char ctl[sizeof(struct cmsghdr) + 20];	/* 20 is size of ipv6_pktinfo */
+	unsigned char ctl[sizeof(struct cmsghdr) + 20]
+			__attribute__ ((aligned (sizeof(__kernel_size_t))));
+			/* 20 is size of ipv6_pktinfo */
 	unsigned char *ctl_buf = ctl;
 	struct msghdr msg_sys;
 	int err, ctl_len, iov_size, total_len;