Merge branch 'bnx2x-disable-GSO-on-too-large-packets'

Daniel Axtens says:

====================
bnx2x: disable GSO on too-large packets

We observed a case where a packet received on an ibmveth device had a
GSO size of around 10kB. This was forwarded by Open vSwitch to a bnx2x
device, where it caused a firmware assert. This is described in detail
at [0].

Ultimately we want a fix in the core, but that is very tricky to
backport. So for now, just stop the bnx2x driver from crashing.

When net-next re-opens I will send the fix to the core and a revert
for this.

v4 changes:
  - fix compilation error with EXPORTs (patch 1)
  - only do slow test if gso_size is greater than 9000 bytes (patch 2)

Thanks,
Daniel

[0]: https://patchwork.ozlabs.org/patch/859410/
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 16 insertions, 0 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index ac89a93b7c83..5ebc0f869720 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -3287,6 +3287,7 @@ int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen);
 void skb_scrub_packet(struct sk_buff *skb, bool xnet);
 unsigned int skb_gso_transport_seglen(const struct sk_buff *skb);
 bool skb_gso_validate_mtu(const struct sk_buff *skb, unsigned int mtu);
+bool skb_gso_validate_mac_len(const struct sk_buff *skb, unsigned int len);
 struct sk_buff *skb_segment(struct sk_buff *skb, netdev_features_t features);
 struct sk_buff *skb_vlan_untag(struct sk_buff *skb);
 int skb_ensure_writable(struct sk_buff *skb, int write_len);
@@ -4120,6 +4121,21 @@ static inline unsigned int skb_gso_network_seglen(const struct sk_buff *skb)
 	return hdr_len + skb_gso_transport_seglen(skb);
 }
 
+/**
+ * skb_gso_mac_seglen - Return length of individual segments of a gso packet
+ *
+ * @skb: GSO skb
+ *
+ * skb_gso_mac_seglen is used to determine the real size of the
+ * individual segments, including MAC/L2, Layer3 (IP, IPv6) and L4
+ * headers (TCP/UDP).
+ */
+static inline unsigned int skb_gso_mac_seglen(const struct sk_buff *skb)
+{
+	unsigned int hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
+	return hdr_len + skb_gso_transport_seglen(skb);
+}
+
 /* Local Checksum Offload.
  * Compute outer checksum based on the assumption that the
  * inner checksum will be offloaded later.