ipv6 equivalent of "ipv4: Avoid reading user iov twice after raw_probe_proto_opt"

[cascardo/linux.git] / net / packet / af_packet.c

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 07ac950..efa8445 100644 (file)
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -378,7 +378,7 @@ static void unregister_prot_hook(struct sock *sk, bool sync)
                __unregister_prot_hook(sk, sync);
 }
 
-static inline __pure struct page *pgv_to_page(void *addr)
+static inline struct page * __pure pgv_to_page(void *addr)
 {
        if (is_vmalloc_addr(addr))
                return vmalloc_to_page(addr);
@@ -2408,6 +2408,10 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
        unsigned short gso_type = 0;
        int hlen, tlen;
        int extra_len = 0;
+       struct iov_iter from;
+       ssize_t n;
+
+       iov_iter_init(&from, WRITE, msg->msg_iov, msg->msg_iovlen, len);
 
        /*
         *      Get and verify the address.
@@ -2446,8 +2450,9 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
 
                len -= vnet_hdr_len;
 
-               err = memcpy_from_msg((void *)&vnet_hdr, msg, vnet_hdr_len);
-               if (err < 0)
+               err = -EFAULT;
+               n = copy_from_iter(&vnet_hdr, vnet_hdr_len, &from);
+               if (n != vnet_hdr_len)
                        goto out_unlock;
 
                if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
@@ -2517,7 +2522,7 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
        }
 
        /* Returns -EFAULT on error */
-       err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
+       err = skb_copy_datagram_from_iter(skb, offset, &from, len);
        if (err)
                goto out_free;
 
@@ -2949,8 +2954,7 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
                        vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
                } /* else everything is zero */
 
-               err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
-                                    vnet_hdr_len);
+               err = memcpy_to_msg(msg, (void *)&vnet_hdr, vnet_hdr_len);
                if (err < 0)
                        goto out_free;
        }