diff options
author | Sasha Levin <levinsasha928@gmail.com> | 2011-09-28 00:40:54 -0400 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2011-10-06 15:39:40 -0400 |
commit | e878d78b9a7403fabc89ecc93c56928b74d14f01 (patch) | |
tree | 669468cdee79d003f70321dcf6d1710b0b6bb852 /drivers/net/virtio_net.c | |
parent | 515853ccecc6987dfb8ed809dd8bf8900286f29e (diff) |
virtio-net: Verify page list size before fitting into skb
This patch verifies that the length of a buffer stored in a linked list
of pages is small enough to fit into a skb.
If the size is larger than a max size of a skb, it means that we shouldn't
go ahead building skbs anyway since we won't be able to send the buffer as
the user requested.
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: virtualization@lists.linux-foundation.org
Cc: netdev@vger.kernel.org
Cc: kvm@vger.kernel.org
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/virtio_net.c')
-rw-r--r-- | drivers/net/virtio_net.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index d6e93ba9ff47..b8225f3b31d1 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c | |||
@@ -195,6 +195,19 @@ static struct sk_buff *page_to_skb(struct virtnet_info *vi, | |||
195 | len -= copy; | 195 | len -= copy; |
196 | offset += copy; | 196 | offset += copy; |
197 | 197 | ||
198 | /* | ||
199 | * Verify that we can indeed put this data into a skb. | ||
200 | * This is here to handle cases when the device erroneously | ||
201 | * tries to receive more than is possible. This is usually | ||
202 | * the case of a broken device. | ||
203 | */ | ||
204 | if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) { | ||
205 | if (net_ratelimit()) | ||
206 | pr_debug("%s: too much data\n", skb->dev->name); | ||
207 | dev_kfree_skb(skb); | ||
208 | return NULL; | ||
209 | } | ||
210 | |||
198 | while (len) { | 211 | while (len) { |
199 | set_skb_frag(skb, page, offset, &len); | 212 | set_skb_frag(skb, page, offset, &len); |
200 | page = (struct page *)page->private; | 213 | page = (struct page *)page->private; |