2020-11-20 23:25:41

by Heiner Kallweit

Subject: [PATCH net-next] net: warn if gso_type isn't set for a GSO SKB

In bug report [0] a warning in r8169 driver was reported that was
caused by an invalid GSO SKB (gso_type was 0). See [1] for a discussion
about this issue. Still the origin of the invalid GSO SKB isn't clear.

It shouldn't be a network drivers task to check for invalid GSO SKB's.
Also, even if issue [0] can be fixed, we can't be sure that a
similar issue doesn't pop up again at another place.
Therefore let gso_features_check() check for such invalid GSO SKB's.

[0] https://bugzilla.kernel.org/show_bug.cgi?id=209423
[1] https://www.spinics.net/lists/netdev/msg690794.html

Signed-off-by: Heiner Kallweit <[email protected]>
---
net/core/dev.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/net/core/dev.c b/net/core/dev.c
index 4bfdcd6b2..3c3070d9d 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3495,6 +3495,11 @@ static netdev_features_t gso_features_check(const struct sk_buff *skb,
if (gso_segs > dev->gso_max_segs)
return features & ~NETIF_F_GSO_MASK;

+ if (!skb_shinfo(skb)->gso_type) {
+ skb_warn_bad_offload(skb);
+ return features & ~NETIF_F_GSO_MASK;
+ }
+
/* Support for GSO partial features requires software
* intervention before we can actually process the packets
* so we need to strip support for any partial features now
--
2.29.2

2020-11-25 00:04:29

by Jakub Kicinski

Subject: Re: [PATCH net-next] net: warn if gso_type isn't set for a GSO SKB

On Sat, 21 Nov 2020 00:22:20 +0100 Heiner Kallweit wrote:
> In bug report [0] a warning in r8169 driver was reported that was
> caused by an invalid GSO SKB (gso_type was 0). See [1] for a discussion
> about this issue. Still the origin of the invalid GSO SKB isn't clear.
>
> It shouldn't be a network drivers task to check for invalid GSO SKB's.
> Also, even if issue [0] can be fixed, we can't be sure that a
> similar issue doesn't pop up again at another place.
> Therefore let gso_features_check() check for such invalid GSO SKB's.
>
> [0] https://bugzilla.kernel.org/show_bug.cgi?id=209423
> [1] https://www.spinics.net/lists/netdev/msg690794.html
>
> Signed-off-by: Heiner Kallweit <[email protected]>

Applied, thanks!