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

Using the net-internal helper __sys_socketpair() allows us to avoid the
internal calls to the sys_socketpair() 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>
This commit is contained in:
Dominik Brodowski 2018-03-13 19:49:23 +01:00
parent b21c8f838a
commit 6debc8d834
3 changed files with 11 additions and 4 deletions

View File

@ -372,5 +372,7 @@ extern int __sys_getsockname(int fd, struct sockaddr __user *usockaddr,
int __user *usockaddr_len); int __user *usockaddr_len);
extern int __sys_getpeername(int fd, struct sockaddr __user *usockaddr, extern int __sys_getpeername(int fd, struct sockaddr __user *usockaddr,
int __user *usockaddr_len); int __user *usockaddr_len);
extern int __sys_socketpair(int family, int type, int protocol,
int __user *usockvec);
#endif /* _LINUX_SOCKET_H */ #endif /* _LINUX_SOCKET_H */

View File

@ -832,7 +832,7 @@ COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args)
ret = __sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2])); ret = __sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2]));
break; break;
case SYS_SOCKETPAIR: case SYS_SOCKETPAIR:
ret = sys_socketpair(a0, a1, a[2], compat_ptr(a[3])); ret = __sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
break; break;
case SYS_SEND: case SYS_SEND:
ret = sys_send(a0, compat_ptr(a1), a[2], a[3]); ret = sys_send(a0, compat_ptr(a1), a[2], a[3]);

View File

@ -1368,8 +1368,7 @@ SYSCALL_DEFINE3(socket, int, family, int, type, int, protocol)
* Create a pair of connected sockets. * Create a pair of connected sockets.
*/ */
SYSCALL_DEFINE4(socketpair, int, family, int, type, int, protocol, int __sys_socketpair(int family, int type, int protocol, int __user *usockvec)
int __user *, usockvec)
{ {
struct socket *sock1, *sock2; struct socket *sock1, *sock2;
int fd1, fd2, err; int fd1, fd2, err;
@ -1454,6 +1453,12 @@ out:
return err; return err;
} }
SYSCALL_DEFINE4(socketpair, int, family, int, type, int, protocol,
int __user *, usockvec)
{
return __sys_socketpair(family, type, protocol, usockvec);
}
/* /*
* Bind a name to a socket. Nothing much to do here since it's * Bind a name to a socket. Nothing much to do here since it's
* the protocol's responsibility to handle the local address. * the protocol's responsibility to handle the local address.
@ -2521,7 +2526,7 @@ SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args)
(int __user *)a[2]); (int __user *)a[2]);
break; break;
case SYS_SOCKETPAIR: case SYS_SOCKETPAIR:
err = sys_socketpair(a0, a1, a[2], (int __user *)a[3]); err = __sys_socketpair(a0, a1, a[2], (int __user *)a[3]);
break; break;
case SYS_SEND: case SYS_SEND:
err = sys_send(a0, (void __user *)a1, a[2], a[3]); err = sys_send(a0, (void __user *)a1, a[2], a[3]);