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

From: Ben Hutchings
Date: Tue Jun 19 2018 - 09:15:40 EST


On Tue, 2018-06-12 at 18:52 +0200, Greg Kroah-Hartman wrote:
> 4.4-stable review patch.ÂÂIf anyone has any objections, please let me know.
>
> ------------------
>
> From: Eric Dumazet <edumazet@xxxxxxxxxx>
>
> [ 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,
> Â if (val == TCP_CA_UNSPEC)
> Â return -EINVAL;
> Â } 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.

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

--
Ben Hutchings, Software Developer  Codethink Ltd
https://www.codethink.co.uk/ Dale House, 35 Dale Street
Manchester, M1 2HF, United Kingdom