X-Git-Url: https://git.stricted.de/?a=blobdiff_plain;f=net%2Fsocket.c;h=773ba3abb10b09c445f2e788a1b01461e5d31a40;hb=36805c5166899a5a013821d3e15b84409ae1ceb6;hp=4ca1526db7562ff7a1ae189a5b51bd6487c045ed;hpb=a2648ebb7ed69ef209d9c8a76fadeb3252d9a023;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git

diff --git a/net/socket.c b/net/socket.c
index 4ca1526db756..773ba3abb10b 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -215,12 +215,13 @@ static int move_addr_to_user(struct sockaddr_storage *kaddr, int klen,
 	int err;
 	int len;
 
+	BUG_ON(klen > sizeof(struct sockaddr_storage));
 	err = get_user(len, ulen);
 	if (err)
 		return err;
 	if (len > klen)
 		len = klen;
-	if (len < 0 || len > sizeof(struct sockaddr_storage))
+	if (len < 0)
 		return -EINVAL;
 	if (len) {
 		if (audit_sockaddr(klen, kaddr))
@@ -1832,8 +1833,10 @@ SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, ubuf, size_t, size,
 	msg.msg_iov = &iov;
 	iov.iov_len = size;
 	iov.iov_base = ubuf;
-	msg.msg_name = (struct sockaddr *)&address;
-	msg.msg_namelen = sizeof(address);
+	/* Save some cycles and don't copy the address if not needed */
+	msg.msg_name = addr ? (struct sockaddr *)&address : NULL;
+	/* We assume all kernel code knows the size of sockaddr_storage */
+	msg.msg_namelen = 0;
 	if (sock->file->f_flags & O_NONBLOCK)
 		flags |= MSG_DONTWAIT;
 	err = sock_recvmsg(sock, &msg, size, flags);
@@ -1956,6 +1959,20 @@ struct used_address {
 	unsigned int name_len;
 };
 
+static int copy_msghdr_from_user(struct msghdr *kmsg,
+				 struct msghdr __user *umsg)
+{
+	if (copy_from_user(kmsg, umsg, sizeof(struct msghdr)))
+		return -EFAULT;
+
+	if (kmsg->msg_namelen < 0)
+		return -EINVAL;
+
+	if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))
+		kmsg->msg_namelen = sizeof(struct sockaddr_storage);
+	return 0;
+}
+
 static int ___sys_sendmsg(struct socket *sock, struct msghdr __user *msg,
 			 struct msghdr *msg_sys, unsigned int flags,
 			 struct used_address *used_address)
@@ -1971,11 +1988,12 @@ static int ___sys_sendmsg(struct socket *sock, struct msghdr __user *msg,
 	int err, ctl_len, total_len;
 
 	err = -EFAULT;
-	if (MSG_CMSG_COMPAT & flags) {
-		if (get_compat_msghdr(msg_sys, msg_compat))
-			return -EFAULT;
-	} else if (copy_from_user(msg_sys, msg, sizeof(struct msghdr)))
-		return -EFAULT;
+	if (MSG_CMSG_COMPAT & flags)
+		err = get_compat_msghdr(msg_sys, msg_compat);
+	else
+		err = copy_msghdr_from_user(msg_sys, msg);
+	if (err)
+		return err;
 
 	if (msg_sys->msg_iovlen > UIO_FASTIOV) {
 		err = -EMSGSIZE;
@@ -2180,11 +2198,12 @@ static int ___sys_recvmsg(struct socket *sock, struct msghdr __user *msg,
 	struct sockaddr __user *uaddr;
 	int __user *uaddr_len;
 
-	if (MSG_CMSG_COMPAT & flags) {
-		if (get_compat_msghdr(msg_sys, msg_compat))
-			return -EFAULT;
-	} else if (copy_from_user(msg_sys, msg, sizeof(struct msghdr)))
-		return -EFAULT;
+	if (MSG_CMSG_COMPAT & flags)
+		err = get_compat_msghdr(msg_sys, msg_compat);
+	else
+		err = copy_msghdr_from_user(msg_sys, msg);
+	if (err)
+		return err;
 
 	if (msg_sys->msg_iovlen > UIO_FASTIOV) {
 		err = -EMSGSIZE;
@@ -2197,16 +2216,14 @@ static int ___sys_recvmsg(struct socket *sock, struct msghdr __user *msg,
 			goto out;
 	}
 
-	/*
-	 *      Save the user-mode address (verify_iovec will change the
-	 *      kernel msghdr to use the kernel address space)
+	/* Save the user-mode address (verify_iovec will change the
+	 * kernel msghdr to use the kernel address space)
 	 */
-
 	uaddr = (__force void __user *)msg_sys->msg_name;
 	uaddr_len = COMPAT_NAMELEN(msg);
-	if (MSG_CMSG_COMPAT & flags) {
+	if (MSG_CMSG_COMPAT & flags)
 		err = verify_compat_iovec(msg_sys, iov, &addr, VERIFY_WRITE);
-	} else
+	else
 		err = verify_iovec(msg_sys, iov, &addr, VERIFY_WRITE);
 	if (err < 0)
 		goto out_freeiov;
@@ -2215,6 +2232,9 @@ static int ___sys_recvmsg(struct socket *sock, struct msghdr __user *msg,
 	cmsg_ptr = (unsigned long)msg_sys->msg_control;
 	msg_sys->msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
 
+	/* We assume all kernel code knows the size of sockaddr_storage */
+	msg_sys->msg_namelen = 0;
+
 	if (sock->file->f_flags & O_NONBLOCK)
 		flags |= MSG_DONTWAIT;
 	err = (nosec ? sock_recvmsg_nosec : sock_recvmsg)(sock, msg_sys,
@@ -2306,8 +2326,10 @@ int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
 		return err;
 
 	err = sock_error(sock->sk);
-	if (err)
+	if (err) {
+		datagrams = err;
 		goto out_put;
+	}
 
 	entry = mmsg;
 	compat_entry = (struct compat_mmsghdr __user *)mmsg;
@@ -2361,31 +2383,31 @@ int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
 			break;
 	}
 
-out_put:
-	fput_light(sock->file, fput_needed);
-
 	if (err == 0)
-		return datagrams;
+		goto out_put;
 
-	if (datagrams != 0) {
+	if (datagrams == 0) {
+		datagrams = err;
+		goto out_put;
+	}
+
+	/*
+	 * We may return less entries than requested (vlen) if the
+	 * sock is non block and there aren't enough datagrams...
+	 */
+	if (err != -EAGAIN) {
 		/*
-		 * We may return less entries than requested (vlen) if the
-		 * sock is non block and there aren't enough datagrams...
+		 * ... or  if recvmsg returns an error after we
+		 * received some datagrams, where we record the
+		 * error to return on the next call or if the
+		 * app asks about it using getsockopt(SO_ERROR).
 		 */
-		if (err != -EAGAIN) {
-			/*
-			 * ... or  if recvmsg returns an error after we
-			 * received some datagrams, where we record the
-			 * error to return on the next call or if the
-			 * app asks about it using getsockopt(SO_ERROR).
-			 */
-			sock->sk->sk_err = -err;
-		}
-
-		return datagrams;
+		sock->sk->sk_err = -err;
 	}
+out_put:
+	fput_light(sock->file, fput_needed);
 
-	return err;
+	return datagrams;
 }
 
 SYSCALL_DEFINE5(recvmmsg, int, fd, struct mmsghdr __user *, mmsg,