Re: [PATCH net-next] ethtool: strset: account for nesting in reply size

On Sat, 2021-06-19 at 01:37 +0200, Michal Kubecek wrote:

On Fri, Jun 18, 2021 at 03:55:02PM -0700, Saeed Mahameed wrote:

quoted

From: Saeed Mahameed <saeedm@nvidia.com>

The cited patch revealed a bug in strset reply size where the
calculation didn't include the 1st nla_nest_start(), a size of 4
Bytes in
strset_fill_reply().

To fix the issue we account for the missing nla_nest 4Bytes by
reporting
them in strset_reply_size()

Before this patch issuing "ethtool -k" command will produce the
following call trace:

[...]

Out of the three fixes, personally I liked most the one which applied
nla_total_len() to calculated length of the nest contents as it IMHO
reflects the message structure best; but adding nla_total_size(0)
also
provides the same result so either does the trick.

Michal

will go with the net fix, thanks for taking a look !