net: simplify cBPF setsockopt compat handling

Add a helper that copies either a native or compat bpf_fprog from
userspace after verifying the length, and remove the compat setsockopt
handlers that now aren't required.

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

1 files changed, 1 insertions, 44 deletions

diff --git a/net/compat.c b/net/compat.c
index 5e3041a2c37d..3e6c2c5ff260 100644
--- a/net/compat.c
+++ b/net/compat.c
@@ -335,49 +335,6 @@ void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm)
 	__scm_destroy(scm);
 }
 
-/* allocate a 64-bit sock_fprog on the user stack for duration of syscall. */
-struct sock_fprog __user *get_compat_bpf_fprog(char __user *optval)
-{
-	struct compat_sock_fprog __user *fprog32 = (struct compat_sock_fprog __user *)optval;
-	struct sock_fprog __user *kfprog = compat_alloc_user_space(sizeof(struct sock_fprog));
-	struct compat_sock_fprog f32;
-	struct sock_fprog f;
-
-	if (copy_from_user(&f32, fprog32, sizeof(*fprog32)))
-		return NULL;
-	memset(&f, 0, sizeof(f));
-	f.len = f32.len;
-	f.filter = compat_ptr(f32.filter);
-	if (copy_to_user(kfprog, &f, sizeof(struct sock_fprog)))
-		return NULL;
-
-	return kfprog;
-}
-EXPORT_SYMBOL_GPL(get_compat_bpf_fprog);
-
-static int do_set_attach_filter(struct socket *sock, int level, int optname,
-				char __user *optval, unsigned int optlen)
-{
-	struct sock_fprog __user *kfprog;
-
-	kfprog = get_compat_bpf_fprog(optval);
-	if (!kfprog)
-		return -EFAULT;
-
-	return sock_setsockopt(sock, level, optname, (char __user *)kfprog,
-			      sizeof(struct sock_fprog));
-}
-
-static int compat_sock_setsockopt(struct socket *sock, int level, int optname,
-				char __user *optval, unsigned int optlen)
-{
-	if (optname == SO_ATTACH_FILTER ||
-	    optname == SO_ATTACH_REUSEPORT_CBPF)
-		return do_set_attach_filter(sock, level, optname,
-					    optval, optlen);
-	return sock_setsockopt(sock, level, optname, optval, optlen);
-}
-
 static int __compat_sys_setsockopt(int fd, int level, int optname,
 				   char __user *optval, unsigned int optlen)
 {
@@ -396,7 +353,7 @@ static int __compat_sys_setsockopt(int fd, int level, int optname,
 		}
 
 		if (level == SOL_SOCKET)
-			err = compat_sock_setsockopt(sock, level,
+			err = sock_setsockopt(sock, level,
 					optname, optval, optlen);
 		else if (sock->ops->compat_setsockopt)
 			err = sock->ops->compat_setsockopt(sock, level,