Re: [PATCH net-next 1/3] net: warn about attempts to register negative ifindex

[Leon Romanovsky <leon@kernel.org>]

On Mon, Aug 14, 2023 at 01:56:25PM -0700, Jakub Kicinski wrote:
> Since the xarray changes we mix returning valid ifindex and negative
> errno in a single int returned from dev_index_reserve(). This depends
> on the fact that ifindexes can't be negative. Otherwise we may insert
> into the xarray and return a very large negative value. This in turn
> may break ERR_PTR().
> 
> OvS is susceptible to this problem and lacking validation (fix posted
> separately for net).
> 
> Reject negative ifindex explicitly. Add a warning because the input
> validation is better handled by the caller.
> 
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> ---
> Turns out concerns from reviewers that callers may not check bounds on
> ifindex were legit...
> ---
>  net/core/dev.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 

Thanks,
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>