llc: convert to getsockopt_iter

Convert LLC socket's getsockopt implementation to use the new
getsockopt_iter callback with sockopt_t.

Key changes:
- Replace (char __user *optval, int __user *optlen) with sockopt_t *opt
- Use opt->optlen for buffer length (input) and returned size (output)
- Use copy_to_iter() instead of put_user()/copy_to_user()
- Add linux/uio.h for copy_to_iter()

Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260507-getsock_two-v2-2-5873111d9c12@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/llc/af_llc.c b/net/llc/af_llc.c
index 1b210db3119e8ecf155f44f4945da5e83bdf013c..35278c519a3050cb75558d58bbee8425a2df50bd 100644 (file)
--- a/net/llc/af_llc.c
+++ b/net/llc/af_llc.c
@@ -27,6 +27,7 @@
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/sched/signal.h>
+#include <linux/uio.h>
 
 #include <net/llc.h>
 #include <net/llc_sap.h>
@@ -1166,25 +1167,21 @@ out:
  *     @sock: Socket to get information from.
  *     @level: Socket level user is requesting operations on.
  *     @optname: Operation name.
- *     @optval: Variable to return operation data in.
- *     @optlen: Length of optval.
+ *     @opt: sockopt context with iterator and length for returning data.
  *
  *     Get connection specific socket information.
  */
 static int llc_ui_getsockopt(struct socket *sock, int level, int optname,
-                            char __user *optval, int __user *optlen)
+                            sockopt_t *opt)
 {
        struct sock *sk = sock->sk;
        struct llc_sock *llc = llc_sk(sk);
-       int val = 0, len = 0, rc = -EINVAL;
+       int val = 0, len, rc = -EINVAL;
 
        lock_sock(sk);
        if (unlikely(level != SOL_LLC))
                goto out;
-       rc = get_user(len, optlen);
-       if (rc)
-               goto out;
-       rc = -EINVAL;
+       len = opt->optlen;
        if (len != sizeof(int))
                goto out;
        switch (optname) {
@@ -1212,7 +1209,8 @@ static int llc_ui_getsockopt(struct socket *sock, int level, int optname,
                goto out;
        }
        rc = 0;
-       if (put_user(len, optlen) || copy_to_user(optval, &val, len))
+       opt->optlen = len;
+       if (copy_to_iter(&val, len, &opt->iter_out) != len)
                rc = -EFAULT;
 out:
        release_sock(sk);
@@ -1239,7 +1237,7 @@ static const struct proto_ops llc_ui_ops = {
        .listen      = llc_ui_listen,
        .shutdown    = llc_ui_shutdown,
        .setsockopt  = llc_ui_setsockopt,
-       .getsockopt  = llc_ui_getsockopt,
+       .getsockopt_iter = llc_ui_getsockopt,
        .sendmsg     = llc_ui_sendmsg,
        .recvmsg     = llc_ui_recvmsg,
        .mmap        = sock_no_mmap,