net: more accurate checksumming in validate_xmit_skb()
skb_csum_hwoffload_help() uses netdev features and skb->csum_not_inet to
determine if skb needs software computation of Internet Checksum or crc32c
(or nothing, if this computation can be done by the hardware). Use it in
place of skb_checksum_help() in validate_xmit_skb() to avoid corruption
of non-GSO SCTP packets having skb->ip_summed equal to CHECKSUM_PARTIAL.
While at it, remove references to skb_csum_off_chk* functions, since they
are not present anymore in Linux _ see commit cf53b1da73bd ("Revert
"net: Add driver helper functions to determine checksum offloadability"").
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/dev.c b/net/core/dev.c
index 71107d1..bb136f7 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2996,6 +2996,17 @@ static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb,
return skb;
}
+int skb_csum_hwoffload_help(struct sk_buff *skb,
+ const netdev_features_t features)
+{
+ if (unlikely(skb->csum_not_inet))
+ return !!(features & NETIF_F_SCTP_CRC) ? 0 :
+ skb_crc32c_csum_help(skb);
+
+ return !!(features & NETIF_F_CSUM_MASK) ? 0 : skb_checksum_help(skb);
+}
+EXPORT_SYMBOL(skb_csum_hwoffload_help);
+
static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev)
{
netdev_features_t features;
@@ -3034,8 +3045,7 @@ static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device
else
skb_set_transport_header(skb,
skb_checksum_start_offset(skb));
- if (!(features & NETIF_F_CSUM_MASK) &&
- skb_checksum_help(skb))
+ if (skb_csum_hwoffload_help(skb, features))
goto out_kfree_skb;
}
}