Re: [PATCH] gre6: Fix reception with IP6_TNL_F_RCV_DSCP_COPY

[David Miller]

From: Mark Tomlinson <mark.tomlinson@xxxxxxxxxxxxxxxxxxx>
Date: Wed, 19 Aug 2020 13:53:58 +1200

> When receiving an IPv4 packet inside an IPv6 GRE packet, and the
> IP6_TNL_F_RCV_DSCP_COPY flag is set on the tunnel, the IPv4 header would
> get corrupted. This is due to the common ip6_tnl_rcv() function assuming
> that the inner header is always IPv6. This patch checks the tunnel
> protocol for IPv4 inner packets, but still defaults to IPv6.
> 
> Fixes: 308edfdf1563 ("gre6: Cleanup GREv6 receive path, call common GRE functions")
> Signed-off-by: Mark Tomlinson <mark.tomlinson@xxxxxxxxxxxxxxxxxxx>

Applied and queued up for -stable, thank you.