Commit 8770cf4a authored by Dominik Brodowski's avatar Dominik Brodowski
Browse files

net: socket: add __compat_sys_getsockopt() helper; remove in-kernel call to compat syscall 

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: default avatarDominik Brodowski <linux@dominikbrodowski.net>
parent 73ee3eaf

net/compat.c

+12 −4
Original line number Diff line number Diff line
@@ -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]);