Re: [PATCH v2 net] mptcp: fix data stream corruption

[Mat Martineau <mathew.j.martineau@linux.intel.com>]

On Tue, 11 May 2021, Paolo Abeni wrote:

> Maxim reported several issues when forcing a TCP transparent proxy
> to use the MPTCP protocol for the inbound connections. He also
> provided a clean reproducer.
>
> The problem boils down to 'mptcp_frag_can_collapse_to()' assuming
> that only MPTCP will use the given page_frag.
>
> If others - e.g. the plain TCP protocol - allocate page fragments,
> we can end-up re-using already allocated memory for mptcp_data_frag.
>
> Fix the issue ensuring that the to-be-expanded data fragment is
> located at the current page frag end.
>
> v1 -> v2:
> - added missing fixes tag (Mat)
>
> Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/178
> Reported-and-tested-by: Maxim Galaganov <max@internet.ru>
> Fixes: 18b683bff89d ("mptcp: queue data for mptcp level retransmission")
> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
> ---
> net/mptcp/protocol.c | 6 ++++++
> 1 file changed, 6 insertions(+)

Paolo -

Thanks for the tag fix. Patch looks good to me:

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>


--
Mat Martineau
Intel