Re: [PATCH net-next] tcp: fix incorrect parameter validation in the do_tcp_getsockopt() function

[Jason Xing]

Hello Paolo,

On Wed, Mar 6, 2024 at 7:36 PM Paolo Abeni <pabeni@xxxxxxxxxx> wrote:
>
> On Wed, 2024-03-06 at 09:57 +0000, Gavrilov Ilia wrote:
> > The 'len' variable can't be negative because all 'min_t' parameters
> > cast to unsigned int, and then the minimum one is chosen.
>
> The above is incorrect, as the 'len' variable is a signed integer

The 'len' variable should be converted to the non-negative value as
this sentence:

len = min_t(unsigned int, len, sizeof(int));

See the comments of min_t(): return minimum of two values, using the
specified type.

After executing the above code, it doesn't make sense to test if 'len
< 0', I think.

Thanks,
Jason

>
>
> The same applies to the following patches.
>
> Cheers,
>
> Paolo
>
>