From: Willem de Bruijn <willemdebruijn.ker...@gmail.com>
Date: Fri, 19 Jan 2018 09:29:18 -0500
> From: Willem de Bruijn <will...@google.com>
>
> Validate gso_type during segmentation as SKB_GSO_DODGY sources
> may pass packets where the gso_type does not match the contents.
>
> Syzkaller was able to enter the SCTP gso handler with a packet of
> gso_type SKB_GSO_TCPV4.
>
> On entry of transport layer gso handlers, verify that the gso_type
> matches the transport protocol.
>
> Fixes: 90017accff61 ("sctp: Add GSO support")
> Link: http://lkml.kernel.org/r/<001a1137452496ffc305617e5...@google.com>
> Reported-by: syzbot+fee64147a25aecd48...@syzkaller.appspotmail.com
> Signed-off-by: Willem de Bruijn <will...@google.com>
>
> ---
> Similar checks existed until removed in commit 5c7cdf339af5 ("gso:
> Remove arbitrary checks for unsupported GSO"). But those were limited
> to the TSO path, not software GSO. I believe that this issue goes
> back further, hence the Fixes at the first user of virtio_net_hdr.
Applied and queued up for -stable, thanks Willem.
