From 25e290eed9c653cc90ac675d64b30b66cffce82f Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Tue, 13 Mar 2018 19:36:54 +0100 Subject: [PATCH] net: socket: add __sys_listen() helper; remove in-kernel call to syscall Using the net-internal helper __sys_listen() allows us to avoid the internal calls to the sys_listen() 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 | 1 + net/compat.c | 2 +- net/socket.c | 9 +++++++-- 3 files changed, 9 insertions(+), 3 deletions(-) diff --git a/include/linux/socket.h b/include/linux/socket.h index 7daa344..7e37af2 100644 --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -367,5 +367,6 @@ 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); +extern int __sys_listen(int fd, int backlog); #endif /* _LINUX_SOCKET_H */ diff --git a/net/compat.c b/net/compat.c index 7ab6352..c80cb97 100644 --- a/net/compat.c +++ b/net/compat.c @@ -820,7 +820,7 @@ COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args) ret = __sys_connect(a0, compat_ptr(a1), a[2]); break; case SYS_LISTEN: - ret = sys_listen(a0, a1); + ret = __sys_listen(a0, a1); break; case SYS_ACCEPT: ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0); diff --git a/net/socket.c b/net/socket.c index 64bdfdf..67d9d70 100644 --- a/net/socket.c +++ b/net/socket.c @@ -1496,7 +1496,7 @@ SYSCALL_DEFINE3(bind, int, fd, struct sockaddr __user *, umyaddr, int, addrlen) * ready for listening. */ -SYSCALL_DEFINE2(listen, int, fd, int, backlog) +int __sys_listen(int fd, int backlog) { struct socket *sock; int err, fput_needed; @@ -1517,6 +1517,11 @@ SYSCALL_DEFINE2(listen, int, fd, int, backlog) return err; } +SYSCALL_DEFINE2(listen, int, fd, int, backlog) +{ + return __sys_listen(fd, backlog); +} + /* * For accept, we attempt to create a new socket, set up the link * with the client, wake up the client, then return the new @@ -2487,7 +2492,7 @@ SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args) err = __sys_connect(a0, (struct sockaddr __user *)a1, a[2]); break; case SYS_LISTEN: - err = sys_listen(a0, a1); + err = __sys_listen(a0, a1); break; case SYS_ACCEPT: err = __sys_accept4(a0, (struct sockaddr __user *)a1, -- 2.7.4