net: Fix possible wrong checksum generation.
Patch cef401de7be8c4e (net: fix possible wrong checksum
generation) fixed wrong checksum calculation but it broke TSO by
defining new GSO type but not a netdev feature for that type.
net_gso_ok() would not allow hardware checksum/segmentation
offload of such packets without the feature.
Following patch fixes TSO and wrong checksum. This patch uses
same logic that Eric Dumazet used. Patch introduces new flag
SKBTX_SHARED_FRAG if at least one frag can be modified by
the user. but SKBTX_SHARED_FRAG flag is kept in skb shared
info tx_flags rather than gso_type.
tx_flags is better compared to gso_type since we can have skb with
shared frag without gso packet. It does not link SHARED_FRAG to
GSO, So there is no need to define netdev feature for this.
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 21a22cc..6c1ad09 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -2326,8 +2326,7 @@
{
int pos = skb_headlen(skb);
- skb_shinfo(skb1)->gso_type = skb_shinfo(skb)->gso_type;
-
+ skb_shinfo(skb)->tx_flags = skb_shinfo(skb1)->tx_flags & SKBTX_SHARED_FRAG;
if (len < pos) /* Split line is inside header. */
skb_split_inside_header(skb, skb1, len, pos);
else /* Second chunk has no header, nothing to copy. */
@@ -2833,7 +2832,7 @@
skb_copy_from_linear_data_offset(skb, offset,
skb_put(nskb, hsize), hsize);
- skb_shinfo(nskb)->gso_type = skb_shinfo(skb)->gso_type;
+ skb_shinfo(nskb)->tx_flags = skb_shinfo(skb)->tx_flags & SKBTX_SHARED_FRAG;
while (pos < offset + len && i < nfrags) {
*frag = skb_shinfo(skb)->frags[i];