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/include/linux/skbuff.h b/include/linux/skbuff.h
index d7573c3..9da9952 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -230,6 +230,13 @@
/* generate wifi status information (where possible) */
SKBTX_WIFI_STATUS = 1 << 4,
+
+ /* This indicates at least one fragment might be overwritten
+ * (as in vmsplice(), sendfile() ...)
+ * If we need to compute a TX checksum, we'll need to copy
+ * all frags to avoid possible bad checksum
+ */
+ SKBTX_SHARED_FRAG = 1 << 5,
};
/*
@@ -307,13 +314,6 @@
SKB_GSO_TCPV6 = 1 << 4,
SKB_GSO_FCOE = 1 << 5,
-
- /* This indicates at least one fragment might be overwritten
- * (as in vmsplice(), sendfile() ...)
- * If we need to compute a TX checksum, we'll need to copy
- * all frags to avoid possible bad checksum
- */
- SKB_GSO_SHARED_FRAG = 1 << 6,
};
#if BITS_PER_LONG > 32
@@ -2220,7 +2220,8 @@
*/
static inline bool skb_has_shared_frag(const struct sk_buff *skb)
{
- return skb_shinfo(skb)->gso_type & SKB_GSO_SHARED_FRAG;
+ return skb_is_nonlinear(skb) &&
+ skb_shinfo(skb)->tx_flags & SKBTX_SHARED_FRAG;
}
/**