net: socket: add __sys_getpeername() helper; remove in-kernel call to syscall
Using the net-internal helper __sys_getpeername() allows us to avoid the
internal calls to the sys_getpeername() 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/net/socket.c b/net/socket.c
index b61e0d2..007fb94 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -1712,8 +1712,8 @@ SYSCALL_DEFINE3(getsockname, int, fd, struct sockaddr __user *, usockaddr,
* name to user space.
*/
-SYSCALL_DEFINE3(getpeername, int, fd, struct sockaddr __user *, usockaddr,
- int __user *, usockaddr_len)
+int __sys_getpeername(int fd, struct sockaddr __user *usockaddr,
+ int __user *usockaddr_len)
{
struct socket *sock;
struct sockaddr_storage address;
@@ -1738,6 +1738,12 @@ SYSCALL_DEFINE3(getpeername, int, fd, struct sockaddr __user *, usockaddr,
return err;
}
+SYSCALL_DEFINE3(getpeername, int, fd, struct sockaddr __user *, usockaddr,
+ int __user *, usockaddr_len)
+{
+ return __sys_getpeername(fd, usockaddr, usockaddr_len);
+}
+
/*
* Send a datagram to a given address. We move the address into kernel
* space and check the user space data area is readable before invoking
@@ -2511,8 +2517,8 @@ SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args)
break;
case SYS_GETPEERNAME:
err =
- sys_getpeername(a0, (struct sockaddr __user *)a1,
- (int __user *)a[2]);
+ __sys_getpeername(a0, (struct sockaddr __user *)a1,
+ (int __user *)a[2]);
break;
case SYS_SOCKETPAIR:
err = sys_socketpair(a0, a1, a[2], (int __user *)a[3]);