4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Willem de Bruijn <willemb@xxxxxxxxxx>
commit 8d74e9f88d65af8bb2e095aff506aa6eac755ada upstream.
skb_warn_bad_offload warns when packets enter the GSO stack that
require skb_checksum_help or vice versa. Do not warn on arbitrary
bad packets. Packet sockets can craft many. Syzkaller was able to
demonstrate another one with eth_type games.
In particular, suppress the warning when segmentation returns an
error, which is for reasons other than checksum offload.
See also commit 36c92474498a ("net: WARN if skb_checksum_help() is
called on skb requiring segmentation") for context on this warning.
Signed-off-by: Willem de Bruijn <willemb@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/core/dev.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2763,7 +2763,7 @@ struct sk_buff *__skb_gso_segment(struct
segs = skb_mac_gso_segment(skb, features);
- if (unlikely(skb_needs_check(skb, tx_path)))
+ if (unlikely(skb_needs_check(skb, tx_path) && !IS_ERR(segs)))
skb_warn_bad_offload(skb);
return segs;