Re: [PATCH 4.4 24/24] net: metrics: add proper netlink validation

Ben Hutchings
2018-06-19T13:15:38Z

On Tue, 2018-06-12 at 18:52 +0200, Greg Kroah-Hartman wrote:
> 4.4-stable review patch.  If anyone has any objections, please let me know.
>
> ------------------
>
> From: Eric Dumazet <edumazet@google.com>
>
> [ Upstream commit 5b5e7a0de2bbf2a1afcd9f49e940010e9fb80d53 ]
[...]
> --- a/net/ipv4/fib_semantics.c
> +++ b/net/ipv4/fib_semantics.c
> @@ -979,6 +979,8 @@ fib_convert_metrics(struct fib_info *fi,
>   if (val == TCP_CA_UNSPEC)
>   return -EINVAL;
>   } else {
> + if (nla_len(nla) != sizeof(u32))
> + return false;

For 4.4 and 4.9, the return value on error needs to be -EINVAL.

Ben.

>   val = nla_get_u32(nla);
>   }
>   if (type == RTAX_ADVMSS && val > 65535 - 40)

--
Ben Hutchings, Software Developer   Codethink Ltd
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