From 6debc8d834ebc73566e5255c565c8fb307be22c5 Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Tue, 13 Mar 2018 19:49:23 +0100 Subject: [PATCH] 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 Cc: netdev@vger.kernel.org Signed-off-by: Dominik Brodowski --- include/linux/socket.h | 2 ++ net/compat.c | 2 +- net/socket.c | 11 ++++++++--- 3 files changed, 11 insertions(+), 4 deletions(-) diff --git a/include/linux/socket.h b/include/linux/socket.h index 9ba003e..dbdddf0 100644 --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -372,5 +372,7 @@ extern int __sys_getsockname(int fd, struct sockaddr __user *usockaddr, int __user *usockaddr_len); extern int __sys_getpeername(int fd, struct sockaddr __user *usockaddr, int __user *usockaddr_len); +extern int __sys_socketpair(int family, int type, int protocol, + int __user *usockvec); #endif /* _LINUX_SOCKET_H */ diff --git a/net/compat.c b/net/compat.c index 74017f6..04db263 100644 --- a/net/compat.c +++ b/net/compat.c @@ -832,7 +832,7 @@ COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args) ret = __sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2])); break; 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; case SYS_SEND: ret = sys_send(a0, compat_ptr(a1), a[2], a[3]); diff --git a/net/socket.c b/net/socket.c index 007fb94..5861821 100644 --- a/net/socket.c +++ b/net/socket.c @@ -1368,8 +1368,7 @@ SYSCALL_DEFINE3(socket, int, family, int, type, int, protocol) * Create a pair of connected sockets. */ -SYSCALL_DEFINE4(socketpair, int, family, int, type, int, protocol, - int __user *, usockvec) +int __sys_socketpair(int family, int type, int protocol, int __user *usockvec) { struct socket *sock1, *sock2; int fd1, fd2, err; @@ -1454,6 +1453,12 @@ out: 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 * 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]); break; 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; case SYS_SEND: err = sys_send(a0, (void __user *)a1, a[2], a[3]); -- 2.7.4