On Sat, Apr 5, 2025 at 4:04 PM Akihiko Odaki <akihiko.od...@daynix.com> wrote:
>
> The goal of commit 7987d2be5a8b ("virtio-net: Copy received header to
> buffer") was to remove the need to patch the (const) input buffer with a
> recomputed UDP checksum by copying headers to a RW region and inject the
> checksum there. The patch computed the checksum only from the header
> fields (missing the rest of the payload) producing an invalid one
> and making guests fail to acquire a DHCP lease.
>
> Fix the issue by copying the entire packet instead of only copying the
> headers.
>
> Fixes: 7987d2be5a8b ("virtio-net: Copy received header to buffer")
> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2727
> Cc: qemu-sta...@nongnu.org
> Signed-off-by: Akihiko Odaki <akihiko.od...@daynix.com>
> ---
> This patch aims to resolves the issue the following one also does:
> https://lore.kernel.org/qemu-devel/20250404151835.328368-1-adam...@scaleway.com
>
> The difference from the mentioned patch is that this patch also
> preserves that the original intent of regressing change, which is to
> remove the need to patch the (const) input buffer with a recomputed UDP
> checksum.
>
> To Antoine Damhet:
> I confirmed that DHCP is currently not working and this patch fixes the
> issue, but I would appreciate if you also confirm the fix as I already
> have done testing badly for the regressing patch.Considering we are about to release, I'd prefer to do the reverting first and refine on the next version. Thanks
