From 211b634b7f1ebc3436d5e8a34810a8eaa1f269d9 Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Tue, 13 Mar 2018 19:18:52 +0100 Subject: [PATCH] net: socket: add __sys_sendto() helper; remove in-kernel call to syscall Using the net-internal helper __sys_sendto() allows us to avoid the internal calls to the sys_sendto() 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 | 3 +++ net/compat.c | 3 ++- net/socket.c | 19 ++++++++++++------- 3 files changed, 17 insertions(+), 8 deletions(-) diff --git a/include/linux/socket.h b/include/linux/socket.h index 40cc93b91628..54b85abc7265 100644 --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -358,5 +358,8 @@ extern int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg, extern int __sys_recvfrom(int fd, void __user *ubuf, size_t size, unsigned int flags, struct sockaddr __user *addr, int __user *addr_len); +extern int __sys_sendto(int fd, void __user *buff, size_t len, + unsigned int flags, struct sockaddr __user *addr, + int addr_len); #endif /* _LINUX_SOCKET_H */ diff --git a/net/compat.c b/net/compat.c index 2d8186c277b2..fc82982d9b84 100644 --- a/net/compat.c +++ b/net/compat.c @@ -838,7 +838,8 @@ COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args) ret = sys_send(a0, compat_ptr(a1), a[2], a[3]); break; case SYS_SENDTO: - ret = sys_sendto(a0, compat_ptr(a1), a[2], a[3], compat_ptr(a[4]), a[5]); + ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3], + compat_ptr(a[4]), a[5]); break; case SYS_RECV: ret = compat_sys_recv(a0, compat_ptr(a1), a[2], a[3]); diff --git a/net/socket.c b/net/socket.c index 712d99d8680f..3f037a21ba5e 100644 --- a/net/socket.c +++ b/net/socket.c @@ -1711,10 +1711,8 @@ SYSCALL_DEFINE3(getpeername, int, fd, struct sockaddr __user *, usockaddr, * space and check the user space data area is readable before invoking * the protocol. */ - -SYSCALL_DEFINE6(sendto, int, fd, void __user *, buff, size_t, len, - unsigned int, flags, struct sockaddr __user *, addr, - int, addr_len) +int __sys_sendto(int fd, void __user *buff, size_t len, unsigned int flags, + struct sockaddr __user *addr, int addr_len) { struct socket *sock; struct sockaddr_storage address; @@ -1752,6 +1750,13 @@ out: return err; } +SYSCALL_DEFINE6(sendto, int, fd, void __user *, buff, size_t, len, + unsigned int, flags, struct sockaddr __user *, addr, + int, addr_len) +{ + return __sys_sendto(fd, buff, len, flags, addr, addr_len); +} + /* * Send a datagram down a socket. */ @@ -1759,7 +1764,7 @@ out: SYSCALL_DEFINE4(send, int, fd, void __user *, buff, size_t, len, unsigned int, flags) { - return sys_sendto(fd, buff, len, flags, NULL, 0); + return __sys_sendto(fd, buff, len, flags, NULL, 0); } /* @@ -2484,8 +2489,8 @@ SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args) err = sys_send(a0, (void __user *)a1, a[2], a[3]); break; case SYS_SENDTO: - err = sys_sendto(a0, (void __user *)a1, a[2], a[3], - (struct sockaddr __user *)a[4], a[5]); + err = __sys_sendto(a0, (void __user *)a1, a[2], a[3], + (struct sockaddr __user *)a[4], a[5]); break; case SYS_RECV: err = sys_recv(a0, (void __user *)a1, a[2], a[3]); -- 2.30.2