packet: fix race condition in packet_set_ring

[pandora-kernel.git] / net / packet / af_packet.c

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 0c21f06..dae9476 100644 (file)
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -1263,10 +1263,10 @@ static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
 
 bool match_fanout_group(struct packet_type *ptype, struct sock * sk)
 {
-       if (ptype->af_packet_priv == (void*)((struct packet_sock *)sk)->fanout)
-               return true;
+       if (sk->sk_family != PF_PACKET)
+               return false;
 
-       return false;
+       return ptype->af_packet_priv == pkt_sk(sk)->fanout;
 }
 
 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
@@ -3077,19 +3077,25 @@ packet_setsockopt(struct socket *sock, int level, int optname, char __user *optv
 
                if (optlen != sizeof(val))
                        return -EINVAL;
-               if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
-                       return -EBUSY;
                if (copy_from_user(&val, optval, sizeof(val)))
                        return -EFAULT;
                switch (val) {
                case TPACKET_V1:
                case TPACKET_V2:
                case TPACKET_V3:
-                       po->tp_version = val;
-                       return 0;
+                       break;
                default:
                        return -EINVAL;
                }
+               lock_sock(sk);
+               if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
+                       ret = -EBUSY;
+               } else {
+                       po->tp_version = val;
+                       ret = 0;
+               }
+               release_sock(sk);
+               return ret;
        }
        case PACKET_RESERVE:
        {
@@ -3560,6 +3566,7 @@ static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
        /* Added to avoid minimal code churn */
        struct tpacket_req *req = &req_u->req;
 
+       lock_sock(sk);
        /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
        if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
                WARN(1, "Tx-ring is not supported.\n");
@@ -3637,7 +3644,6 @@ static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
                        goto out;
        }
 
-       lock_sock(sk);
 
        /* Detach socket from network */
        spin_lock(&po->bind_lock);
@@ -3686,11 +3692,11 @@ static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
                if (!tx_ring)
                        prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
        }
-       release_sock(sk);
 
        if (pg_vec)
                free_pg_vec(pg_vec, order, req->tp_block_nr);
 out:
+       release_sock(sk);
        return err;
 }