From b21c8f838a0e5b84c0d78fd9ed6b9f2cf97afbe9 Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Tue, 13 Mar 2018 19:47:00 +0100 Subject: [PATCH] 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 Cc: netdev@vger.kernel.org Signed-off-by: Dominik Brodowski --- include/linux/socket.h | 2 ++ net/compat.c | 2 +- net/socket.c | 14 ++++++++++---- 3 files changed, 13 insertions(+), 5 deletions(-) diff --git a/include/linux/socket.h b/include/linux/socket.h index ef0226a61b03..9ba003e92fea 100644 --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -370,5 +370,7 @@ extern int __sys_connect(int fd, struct sockaddr __user *uservaddr, extern int __sys_listen(int fd, int backlog); 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); #endif /* _LINUX_SOCKET_H */ diff --git a/net/compat.c b/net/compat.c index efd28d02608c..74017f618eb1 100644 --- a/net/compat.c +++ b/net/compat.c @@ -829,7 +829,7 @@ COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args) ret = __sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2])); break; case SYS_GETPEERNAME: - ret = sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2])); + 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])); diff --git a/net/socket.c b/net/socket.c index b61e0d20f37b..007fb9483279 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]);