net: socket: add __sys_connect() helper; remove in-kernel call to syscall

Using the net-internal helper __sys_connect() allows us to avoid the
internal calls to the sys_connect() syscall.

This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net

Cc: David S. Miller <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

diff --git a/include/linux/socket.h b/include/linux/socket.h
index e9cee272da1375ef4d1eb2269dd0eaf02d86cced..7daa344d73201d87e77e9788f1a6bc2d260573f9 100644 (file)
--- a/include/linux/socket.h
+++ b/include/linux/socket.h
@@ -365,5 +365,7 @@ extern int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr,
                         int __user *upeer_addrlen, int flags);
 extern int __sys_socket(int family, int type, int protocol);
 extern int __sys_bind(int fd, struct sockaddr __user *umyaddr, int addrlen);
+extern int __sys_connect(int fd, struct sockaddr __user *uservaddr,
+                        int addrlen);
 
 #endif /* _LINUX_SOCKET_H */

diff --git a/net/compat.c b/net/compat.c
index bba555b1d863e4048402f6d5462aea37acb09a59..7ab6352268f344d1cee5bb3a9bf84a1f30b94ed0 100644 (file)
--- a/net/compat.c
+++ b/net/compat.c
@@ -817,7 +817,7 @@ COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args)
                ret = __sys_bind(a0, compat_ptr(a1), a[2]);
                break;
        case SYS_CONNECT:
-               ret = sys_connect(a0, compat_ptr(a1), a[2]);
+               ret = __sys_connect(a0, compat_ptr(a1), a[2]);
                break;
        case SYS_LISTEN:
                ret = sys_listen(a0, a1);

diff --git a/net/socket.c b/net/socket.c
index 291cdae973411ba1596c1651c8a5abdda149c974..64bdfdf6c6e7d6c5f154d21a8d9697c86fa5552b 100644 (file)
--- a/net/socket.c
+++ b/net/socket.c
@@ -1633,8 +1633,7 @@ SYSCALL_DEFINE3(accept, int, fd, struct sockaddr __user *, upeer_sockaddr,
  *     include the -EINPROGRESS status for such sockets.
  */
 
-SYSCALL_DEFINE3(connect, int, fd, struct sockaddr __user *, uservaddr,
-               int, addrlen)
+int __sys_connect(int fd, struct sockaddr __user *uservaddr, int addrlen)
 {
        struct socket *sock;
        struct sockaddr_storage address;
@@ -1660,6 +1659,12 @@ out:
        return err;
 }
 
+SYSCALL_DEFINE3(connect, int, fd, struct sockaddr __user *, uservaddr,
+               int, addrlen)
+{
+       return __sys_connect(fd, uservaddr, addrlen);
+}
+
 /*
  *     Get the local address ('name') of a socket object. Move the obtained
  *     name to user space.
@@ -2479,7 +2484,7 @@ SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args)
                err = __sys_bind(a0, (struct sockaddr __user *)a1, a[2]);
                break;
        case SYS_CONNECT:
-               err = sys_connect(a0, (struct sockaddr __user *)a1, a[2]);
+               err = __sys_connect(a0, (struct sockaddr __user *)a1, a[2]);
                break;
        case SYS_LISTEN:
                err = sys_listen(a0, a1);