net: filter: let unattached filters use sock_fprog_kern

The sk_unattached_filter_create() API is used by BPF filters that
are not directly attached or related to sockets, and are used in
team, ptp, xt_bpf, cls_bpf, etc. As such all users do their own
internal managment of obtaining filter blocks and thus already
have them in kernel memory and set up before calling into
sk_unattached_filter_create(). As a result, due to __user annotation
in sock_fprog, sparse triggers false positives (incorrect type in
assignment [different address space]) when filters are set up before
passing them to sk_unattached_filter_create(). Therefore, let
sk_unattached_filter_create() API use sock_fprog_kern to overcome
this issue.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/filter.c b/net/core/filter.c
index b3b0889..2c2d35d 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -1585,7 +1585,7 @@
  * a negative errno code is returned. On success the return is zero.
  */
 int sk_unattached_filter_create(struct sk_filter **pfp,
-				struct sock_fprog *fprog)
+				struct sock_fprog_kern *fprog)
 {
 	unsigned int fsize = sk_filter_proglen(fprog);
 	struct sk_filter *fp;
diff --git a/net/core/ptp_classifier.c b/net/core/ptp_classifier.c
index 37d8615..d3027a7 100644
--- a/net/core/ptp_classifier.c
+++ b/net/core/ptp_classifier.c
@@ -133,7 +133,7 @@
 		{ 0x16,  0,  0, 0x00000000 },
 		{ 0x06,  0,  0, 0x00000000 },
 	};
-	struct sock_fprog ptp_prog = {
+	struct sock_fprog_kern ptp_prog = {
 		.len = ARRAY_SIZE(ptp_filter), .filter = ptp_filter,
 	};