[PATCH 027/109] net: socket: add __compat_sys_getsockopt() helper; remove in-kernel call to compat syscall
From: Dominik Brodowski <linux@dominikbrodowski.net>
Date: 2018-03-29 11:48:40
Also in:
lkml, netdev
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Using the net-internal helper __compat_sys_getsockopt() allows us to avoid the internal calls to the compat_sys_getsockopt() 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 <davem@davemloft.net> Cc: netdev@vger.kernel.org Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> --- net/compat.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/net/compat.c b/net/compat.c
index 75bfcbbb2e3e..cdf5b0c1b962 100644
--- a/net/compat.c
+++ b/net/compat.c@@ -509,8 +509,9 @@ int compat_sock_get_timestampns(struct sock *sk, struct timespec __user *usersta } EXPORT_SYMBOL(compat_sock_get_timestampns); -COMPAT_SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname, - char __user *, optval, int __user *, optlen) +static int __compat_sys_getsockopt(int fd, int level, int optname, + char __user *optval, + int __user *optlen) { int err; struct socket *sock = sockfd_lookup(fd, &err);
@@ -536,6 +537,12 @@ COMPAT_SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname, return err; } +COMPAT_SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname, + char __user *, optval, int __user *, optlen) +{ + return __compat_sys_getsockopt(fd, level, optname, optval, optlen); +} + struct compat_group_req { __u32 gr_interface; struct __kernel_sockaddr_storage gr_group
@@ -874,8 +881,9 @@ COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args) compat_ptr(a[3]), a[4]); break; case SYS_GETSOCKOPT: - ret = compat_sys_getsockopt(a0, a1, a[2], - compat_ptr(a[3]), compat_ptr(a[4])); + ret = __compat_sys_getsockopt(a0, a1, a[2], + compat_ptr(a[3]), + compat_ptr(a[4])); break; case SYS_SENDMSG: ret = compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
--
2.16.3