net: remove compat_sys_{get,set}sockopt

Now that the ->compat_{get,set}sockopt proto_ops methods are gone
there is no good reason left to keep the compat syscalls separate.

This fixes the odd use of unsigned int for the compat_setsockopt
optlen and the missing sock_use_custom_sol_socket.

It would also easily allow running the eBPF hooks for the compat
syscalls, but such a large change in behavior does not belong into
a consolidation patch like this one.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 17 insertions, 87 deletions

diff --git a/net/compat.c b/net/compat.c
index 3e6c2c5ff260..091875bd6210 100644
--- a/net/compat.c
+++ b/net/compat.c
@@ -335,77 +335,6 @@ void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm)
 	__scm_destroy(scm);
 }
 
-static int __compat_sys_setsockopt(int fd, int level, int optname,
-				   char __user *optval, unsigned int optlen)
-{
-	int err;
-	struct socket *sock;
-
-	if (optlen > INT_MAX)
-		return -EINVAL;
-
-	sock = sockfd_lookup(fd, &err);
-	if (sock) {
-		err = security_socket_setsockopt(sock, level, optname);
-		if (err) {
-			sockfd_put(sock);
-			return err;
-		}
-
-		if (level == SOL_SOCKET)
-			err = sock_setsockopt(sock, level,
-					optname, optval, optlen);
-		else if (sock->ops->compat_setsockopt)
-			err = sock->ops->compat_setsockopt(sock, level,
-					optname, optval, optlen);
-		else
-			err = sock->ops->setsockopt(sock, level,
-					optname, optval, optlen);
-		sockfd_put(sock);
-	}
-	return err;
-}
-
-COMPAT_SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
-		       char __user *, optval, unsigned int, optlen)
-{
-	return __compat_sys_setsockopt(fd, level, optname, optval, 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);
-
-	if (sock) {
-		err = security_socket_getsockopt(sock, level, optname);
-		if (err) {
-			sockfd_put(sock);
-			return err;
-		}
-
-		if (level == SOL_SOCKET)
-			err = sock_getsockopt(sock, level,
-					optname, optval, optlen);
-		else if (sock->ops->compat_getsockopt)
-			err = sock->ops->compat_getsockopt(sock, level,
-					optname, optval, optlen);
-		else
-			err = sock->ops->getsockopt(sock, level,
-					optname, optval, optlen);
-		sockfd_put(sock);
-	}
-	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);
-}
-
 /* Argument list sizes for compat_sys_socketcall */
 #define AL(x) ((x) * sizeof(u32))
 static unsigned char nas[21] = {
@@ -565,13 +494,11 @@ COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args)
 		ret = __sys_shutdown(a0, a1);
 		break;
 	case SYS_SETSOCKOPT:
-		ret = __compat_sys_setsockopt(a0, a1, a[2],
-					      compat_ptr(a[3]), a[4]);
+		ret = __sys_setsockopt(a0, a1, a[2], 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 = __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]);
diff --git a/net/socket.c b/net/socket.c
index b79376b17b45..dec345982abb 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -2094,9 +2094,8 @@ static bool sock_use_custom_sol_socket(const struct socket *sock)
  *	Set a socket option. Because we don't know the option lengths we have
  *	to pass the user mode parameter for the protocols to sort out.
  */
-
-static int __sys_setsockopt(int fd, int level, int optname,
-			    char __user *optval, int optlen)
+int __sys_setsockopt(int fd, int level, int optname, char __user *optval,
+		int optlen)
 {
 	mm_segment_t oldfs = get_fs();
 	char *kernel_optval = NULL;
@@ -2114,8 +2113,10 @@ static int __sys_setsockopt(int fd, int level, int optname,
 	if (err)
 		goto out_put;
 
-	err = BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock->sk, &level, &optname,
-					     optval, &optlen, &kernel_optval);
+	if (!in_compat_syscall())
+		err = BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock->sk, &level, &optname,
+						     optval, &optlen,
+						     &kernel_optval);
 	if (err < 0)
 		goto out_put;
 	if (err > 0) {
@@ -2154,9 +2155,8 @@ SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
  *	Get a socket option. Because we don't know the option lengths we have
  *	to pass a user mode parameter for the protocols to sort out.
  */
-
-static int __sys_getsockopt(int fd, int level, int optname,
-			    char __user *optval, int __user *optlen)
+int __sys_getsockopt(int fd, int level, int optname, char __user *optval,
+		int __user *optlen)
 {
 	int err, fput_needed;
 	struct socket *sock;
@@ -2170,7 +2170,8 @@ static int __sys_getsockopt(int fd, int level, int optname,
 	if (err)
 		goto out_put;
 
-	max_optlen = BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen);
+	if (!in_compat_syscall())
+		max_optlen = BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen);
 
 	if (level == SOL_SOCKET)
 		err = sock_getsockopt(sock, level, optname, optval, optlen);
@@ -2178,8 +2179,10 @@ static int __sys_getsockopt(int fd, int level, int optname,
 		err = sock->ops->getsockopt(sock, level, optname, optval,
 					    optlen);
 
-	err = BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock->sk, level, optname, optval,
-					     optlen, max_optlen, err);
+	if (!in_compat_syscall())
+		err = BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock->sk, level, optname,
+						     optval, optlen, max_optlen,
+						     err);
 out_put:
 	fput_light(sock->file, fput_needed);
 	return err;