[PATCH net-next 5/7] phonet: pep: convert getsockopt to sockopt_t

[Breno Leitao]

Continue converting the proto-layer getsockopt callbacks to the
sockopt_t interface, splitting pep_getsockopt() into a
do_pep_getsockopt() helper that takes a sockopt_t.

The thin pep_getsockopt() wrapper keeps its __user signature for now:
it builds a user-backed sockopt_t with sockopt_init_user(), calls the
helper, and writes the returned length back to optlen. The helper uses
copy_to_iter() instead of copy_to_user(). No functional change.

Signed-off-by: Breno Leitao <leitao@xxxxxxxxxx>
---
 net/phonet/pep.c | 36 ++++++++++++++++++++++++++----------
 1 file changed, 26 insertions(+), 10 deletions(-)

diff --git a/net/phonet/pep.c b/net/phonet/pep.c
index 60d1a5375725b..c7f4ce894af56 100644
--- a/net/phonet/pep.c
+++ b/net/phonet/pep.c
@@ -1078,17 +1078,11 @@ static int pep_setsockopt(struct sock *sk, int level, int optname,
 	return err;
 }
 
-static int pep_getsockopt(struct sock *sk, int level, int optname,
-				char __user *optval, int __user *optlen)
+static int do_pep_getsockopt(struct sock *sk, int optname, sockopt_t *opt)
 {
 	struct pep_sock *pn = pep_sk(sk);
 	int len, val;
 
-	if (level != SOL_PNPIPE)
-		return -ENOPROTOOPT;
-	if (get_user(len, optlen))
-		return -EFAULT;
-
 	switch (optname) {
 	case PNPIPE_ENCAP:
 		val = pn->ifindex ? PNPIPE_ENCAP_IP : PNPIPE_ENCAP_NONE;
@@ -1112,11 +1106,33 @@ static int pep_getsockopt(struct sock *sk, int level, int optname,
 		return -ENOPROTOOPT;
 	}
 
-	len = min_t(unsigned int, sizeof(int), len);
-	if (put_user(len, optlen))
+	len = min_t(unsigned int, sizeof(int), opt->optlen);
+	opt->optlen = len;
+	if (copy_to_iter(&val, len, &opt->iter_out) != len)
 		return -EFAULT;
-	if (copy_to_user(optval, &val, len))
+	return 0;
+}
+
+static int pep_getsockopt(struct sock *sk, int level, int optname,
+			  char __user *optval, int __user *optlen)
+{
+	sockopt_t opt;
+	int err;
+
+	if (level != SOL_PNPIPE)
+		return -ENOPROTOOPT;
+
+	err = sockopt_init_user(&opt, optval, optlen);
+	if (err)
+		return err;
+
+	err = do_pep_getsockopt(sk, optname, &opt);
+	if (err)
+		return err;
+
+	if (put_user(opt.optlen, optlen))
 		return -EFAULT;
+
 	return 0;
 }
 

-- 
2.53.0-Meta