af_packet: packet_getsockopt() cleanup

Factorize code, since most fetched values are int type.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 8 insertions, 38 deletions

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 40053a08f00..0f661745df0 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -3224,10 +3224,10 @@ static int packet_getsockopt(struct socket *sock, int level, int optname,
                              char __user *optval, int __user *optlen)
 {
         int len;
-        int val;
+        int val, lv = sizeof(val);
         struct sock *sk = sock->sk;
         struct packet_sock *po = pkt_sk(sk);
-        void *data;
+        void *data = &val;
         struct tpacket_stats st;
         union tpacket_stats_u st_u;
 
@@ -3242,21 +3242,17 @@ static int packet_getsockopt(struct socket *sock, int level, int optname,
 
         switch (optname) {
         case PACKET_STATISTICS:
-                if (po->tp_version == TPACKET_V3) {
-                        len = sizeof(struct tpacket_stats_v3);
-                } else {
-                        if (len > sizeof(struct tpacket_stats))
-                                len = sizeof(struct tpacket_stats);
-                }
                 spin_lock_bh(&sk->sk_receive_queue.lock);
                 if (po->tp_version == TPACKET_V3) {
+                        lv = sizeof(struct tpacket_stats_v3);
                         memcpy(&st_u.stats3, &po->stats,
-                        sizeof(struct tpacket_stats));
+                               sizeof(struct tpacket_stats));
                         st_u.stats3.tp_freeze_q_cnt =
-                        po->stats_u.stats3.tp_freeze_q_cnt;
+                                        po->stats_u.stats3.tp_freeze_q_cnt;
                         st_u.stats3.tp_packets += po->stats.tp_drops;
                         data = &st_u.stats3;
                 } else {
+                        lv = sizeof(struct tpacket_stats);
                         st = po->stats;
                         st.tp_packets += st.tp_drops;
                         data = &st;
@@ -3265,31 +3261,16 @@ static int packet_getsockopt(struct socket *sock, int level, int optname,
                 spin_unlock_bh(&sk->sk_receive_queue.lock);
                 break;
         case PACKET_AUXDATA:
-                if (len > sizeof(int))
-                        len = sizeof(int);
                 val = po->auxdata;
-
-                data = &val;
                 break;
         case PACKET_ORIGDEV:
-                if (len > sizeof(int))
-                        len = sizeof(int);
                 val = po->origdev;
-
-                data = &val;
                 break;
         case PACKET_VNET_HDR:
-                if (len > sizeof(int))
-                        len = sizeof(int);
                 val = po->has_vnet_hdr;
-
-                data = &val;
                 break;
         case PACKET_VERSION:
-                if (len > sizeof(int))
-                        len = sizeof(int);
                 val = po->tp_version;
-                data = &val;
                 break;
         case PACKET_HDRLEN:
                 if (len > sizeof(int))
@@ -3309,39 +3290,28 @@ static int packet_getsockopt(struct socket *sock, int level, int optname,
                 default:
                         return -EINVAL;
                 }
-                data = &val;
                 break;
         case PACKET_RESERVE:
-                if (len > sizeof(unsigned int))
-                        len = sizeof(unsigned int);
                 val = po->tp_reserve;
-                data = &val;
                 break;
         case PACKET_LOSS:
-                if (len > sizeof(unsigned int))
-                        len = sizeof(unsigned int);
                 val = po->tp_loss;
-                data = &val;
                 break;
         case PACKET_TIMESTAMP:
-                if (len > sizeof(int))
-                        len = sizeof(int);
                 val = po->tp_tstamp;
-                data = &val;
                 break;
         case PACKET_FANOUT:
-                if (len > sizeof(int))
-                        len = sizeof(int);
                 val = (po->fanout ?
                        ((u32)po->fanout->id |
                         ((u32)po->fanout->type << 16)) :
                        0);
-                data = &val;
                 break;
         default:
                 return -ENOPROTOOPT;
         }
 
+        if (len > lv)
+                len = lv;
         if (put_user(len, optlen))
                 return -EFAULT;
         if (copy_to_user(optval, data, len))