From 005a1aeac46666e2805f316596893ebd2a3c12e7 Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Tue, 13 Mar 2018 20:07:05 +0100 Subject: [PATCH] net: socket: add __sys_shutdown() helper; remove in-kernel call to syscall Using the net-internal helper __sys_shutdown() allows us to avoid the internal calls to the sys_shutdown() 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 dbdddf0d079e..b205138b69f1 100644 --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -374,5 +374,6 @@ 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); +extern int __sys_shutdown(int fd, int how); #endif /* _LINUX_SOCKET_H */ diff --git a/net/compat.c b/net/compat.c index 04db26316438..f1ec23e9dfce 100644 --- a/net/compat.c +++ b/net/compat.c @@ -849,7 +849,7 @@ COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args) compat_ptr(a[4]), compat_ptr(a[5])); break; case SYS_SHUTDOWN: - ret = sys_shutdown(a0, a1); + ret = __sys_shutdown(a0, a1); break; case SYS_SETSOCKOPT: ret = compat_sys_setsockopt(a0, a1, a[2], diff --git a/net/socket.c b/net/socket.c index 5861821f46f5..ad5dfd6a1d59 100644 --- a/net/socket.c +++ b/net/socket.c @@ -1942,7 +1942,7 @@ out_put: * Shutdown a socket. */ -SYSCALL_DEFINE2(shutdown, int, fd, int, how) +int __sys_shutdown(int fd, int how) { int err, fput_needed; struct socket *sock; @@ -1957,6 +1957,11 @@ SYSCALL_DEFINE2(shutdown, int, fd, int, how) return err; } +SYSCALL_DEFINE2(shutdown, int, fd, int, how) +{ + return __sys_shutdown(fd, how); +} + /* A couple of helpful macros for getting the address of the 32/64 bit * fields which are the same type (int / unsigned) on our platforms. */ @@ -2544,7 +2549,7 @@ SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args) (int __user *)a[5]); break; case SYS_SHUTDOWN: - err = sys_shutdown(a0, a1); + err = __sys_shutdown(a0, a1); break; case SYS_SETSOCKOPT: err = sys_setsockopt(a0, a1, a[2], (char __user *)a[3], a[4]);