Bluetooth: L2CAP: convert to getsockopt_iter

Convert L2CAP 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 *sopt
- Use sopt->optlen for buffer length (input)
- Use copy_to_iter() instead of put_user()/copy_to_user()
- Add linux/uio.h for copy_to_iter()

The sockopt_t parameter is named sopt rather than opt to avoid
collision with the existing local u32 opt used by L2CAP_LM. The same
naming is reused for the new u32 helper in l2cap_sock_getsockopt(),
with mtu and mval helpers covering the u16 and u8 cases.

Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index c138aa4ae26690277b812a376835872aea7e3ddf..025329636353db4ad62a630948c1cb2319d499bb 100644 (file)
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -31,6 +31,7 @@
 #include <linux/export.h>
 #include <linux/filter.h>
 #include <linux/sched/signal.h>
+#include <linux/uio.h>
 
 #include <net/bluetooth/bluetooth.h>
 #include <net/bluetooth/hci_core.h>
@@ -438,7 +439,7 @@ static int l2cap_get_mode(struct l2cap_chan *chan)
 }
 
 static int l2cap_sock_getsockopt_old(struct socket *sock, int optname,
-                                    char __user *optval, int __user *optlen)
+                                    sockopt_t *sopt)
 {
        struct sock *sk = sock->sk;
        struct l2cap_chan *chan = l2cap_pi(sk)->chan;
@@ -450,8 +451,7 @@ static int l2cap_sock_getsockopt_old(struct socket *sock, int optname,
 
        BT_DBG("sk %p", sk);
 
-       if (get_user(len, optlen))
-               return -EFAULT;
+       len = sopt->optlen;
 
        lock_sock(sk);
 
@@ -493,7 +493,7 @@ static int l2cap_sock_getsockopt_old(struct socket *sock, int optname,
                BT_DBG("mode 0x%2.2x", chan->mode);
 
                len = min(len, sizeof(opts));
-               if (copy_to_user(optval, (char *) &opts, len))
+               if (copy_to_iter(&opts, len, &sopt->iter_out) != len)
                        err = -EFAULT;
 
                break;
@@ -525,7 +525,8 @@ static int l2cap_sock_getsockopt_old(struct socket *sock, int optname,
                if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
                        opt |= L2CAP_LM_RELIABLE;
 
-               if (put_user(opt, (u32 __user *) optval))
+               if (copy_to_iter(&opt, sizeof(opt), &sopt->iter_out) !=
+                   sizeof(opt))
                        err = -EFAULT;
 
                break;
@@ -543,7 +544,7 @@ static int l2cap_sock_getsockopt_old(struct socket *sock, int optname,
                memcpy(cinfo.dev_class, chan->conn->hcon->dev_class, 3);
 
                len = min(len, sizeof(cinfo));
-               if (copy_to_user(optval, (char *) &cinfo, len))
+               if (copy_to_iter(&cinfo, len, &sopt->iter_out) != len)
                        err = -EFAULT;
 
                break;
@@ -558,25 +559,26 @@ static int l2cap_sock_getsockopt_old(struct socket *sock, int optname,
 }
 
 static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname,
-                                char __user *optval, int __user *optlen)
+                                sockopt_t *sopt)
 {
        struct sock *sk = sock->sk;
        struct l2cap_chan *chan = l2cap_pi(sk)->chan;
        struct bt_security sec;
        struct bt_power pwr;
-       u32 phys;
        int len, mode, err = 0;
+       u32 opt;
+       u16 mtu;
+       u8 mval;
 
        BT_DBG("sk %p", sk);
 
        if (level == SOL_L2CAP)
-               return l2cap_sock_getsockopt_old(sock, optname, optval, optlen);
+               return l2cap_sock_getsockopt_old(sock, optname, sopt);
 
        if (level != SOL_BLUETOOTH)
                return -ENOPROTOOPT;
 
-       if (get_user(len, optlen))
-               return -EFAULT;
+       len = sopt->optlen;
 
        lock_sock(sk);
 
@@ -600,7 +602,7 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname,
                }
 
                len = min_t(unsigned int, len, sizeof(sec));
-               if (copy_to_user(optval, (char *) &sec, len))
+               if (copy_to_iter(&sec, len, &sopt->iter_out) != len)
                        err = -EFAULT;
 
                break;
@@ -611,15 +613,17 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname,
                        break;
                }
 
-               if (put_user(test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags),
-                            (u32 __user *) optval))
+               opt = test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
+               if (copy_to_iter(&opt, sizeof(opt), &sopt->iter_out) !=
+                   sizeof(opt))
                        err = -EFAULT;
 
                break;
 
        case BT_FLUSHABLE:
-               if (put_user(test_bit(FLAG_FLUSHABLE, &chan->flags),
-                            (u32 __user *) optval))
+               opt = test_bit(FLAG_FLUSHABLE, &chan->flags);
+               if (copy_to_iter(&opt, sizeof(opt), &sopt->iter_out) !=
+                   sizeof(opt))
                        err = -EFAULT;
 
                break;
@@ -634,13 +638,15 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname,
                pwr.force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
 
                len = min_t(unsigned int, len, sizeof(pwr));
-               if (copy_to_user(optval, (char *) &pwr, len))
+               if (copy_to_iter(&pwr, len, &sopt->iter_out) != len)
                        err = -EFAULT;
 
                break;
 
        case BT_CHANNEL_POLICY:
-               if (put_user(chan->chan_policy, (u32 __user *) optval))
+               opt = chan->chan_policy;
+               if (copy_to_iter(&opt, sizeof(opt), &sopt->iter_out) !=
+                   sizeof(opt))
                        err = -EFAULT;
                break;
 
@@ -655,7 +661,9 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname,
                        break;
                }
 
-               if (put_user(chan->omtu, (u16 __user *) optval))
+               mtu = chan->omtu;
+               if (copy_to_iter(&mtu, sizeof(mtu), &sopt->iter_out) !=
+                   sizeof(mtu))
                        err = -EFAULT;
                break;
 
@@ -665,7 +673,9 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname,
                        break;
                }
 
-               if (put_user(chan->imtu, (u16 __user *) optval))
+               mtu = chan->imtu;
+               if (copy_to_iter(&mtu, sizeof(mtu), &sopt->iter_out) !=
+                   sizeof(mtu))
                        err = -EFAULT;
                break;
 
@@ -675,9 +685,10 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname,
                        break;
                }
 
-               phys = hci_conn_get_phy(chan->conn->hcon);
+               opt = hci_conn_get_phy(chan->conn->hcon);
 
-               if (put_user(phys, (u32 __user *) optval))
+               if (copy_to_iter(&opt, sizeof(opt), &sopt->iter_out) !=
+                   sizeof(opt))
                        err = -EFAULT;
                break;
 
@@ -698,7 +709,9 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname,
                        break;
                }
 
-               if (put_user(mode, (u8 __user *) optval))
+               mval = mode;
+               if (copy_to_iter(&mval, sizeof(mval), &sopt->iter_out) !=
+                   sizeof(mval))
                        err = -EFAULT;
                break;
 
@@ -2039,7 +2052,7 @@ static const struct proto_ops l2cap_sock_ops = {
        .socketpair     = sock_no_socketpair,
        .shutdown       = l2cap_sock_shutdown,
        .setsockopt     = l2cap_sock_setsockopt,
-       .getsockopt     = l2cap_sock_getsockopt
+       .getsockopt_iter = l2cap_sock_getsockopt
 };
 
 static const struct net_proto_family l2cap_sock_family_ops = {