Re: [PATCH][net-next] nexthop: fix incorrect allocation failure on nhg->spare

From: Nikolay Aleksandrov
Date: Thu May 28 2020 - 10:53:31 EST


On 28/05/2020 17:51, Colin King wrote:
> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>
> The allocation failure check for nhg->spare is currently checking
> the pointer nhg rather than nhg->spare which is never false. Fix
> this by checking nhg->spare instead.
>
> Addresses-Coverity: ("Logically dead code")
> Fixes: 430a049190de ("nexthop: Add support for nexthop groups")
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> ---
> net/ipv4/nexthop.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c
> index ebafa5ed91ac..97423d6f2de9 100644
> --- a/net/ipv4/nexthop.c
> +++ b/net/ipv4/nexthop.c
> @@ -1185,7 +1185,7 @@ static struct nexthop *nexthop_create_group(struct net *net,
>
> /* spare group used for removals */
> nhg->spare = nexthop_grp_alloc(num_nh);
> - if (!nhg) {
> + if (!nhg->spare) {
> kfree(nhg);
> kfree(nh);
> return NULL;
>

Good catch, embarrassing copy paste error :-/
Acked-by: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx>