Re: [PATCH] rtnetlink: Fix an error handling path in rtnl_newlink()

[Kuniyuki Iwashima <kuniyu@amazon.com>]

From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Date: Sat, 26 Oct 2024 16:17:44 +0200
> When some code has been moved in the commit in Fixes, some "return err;"
> have correctly been changed in goto <some_where_in_the_error_handling_path>
> but this one was missed.
> 
> Should "ops->maxtype > RTNL_MAX_TYPE" happen, then some resources would
> leak.
> 
> Go through the error handling path to fix these leaks.
> 
> Fixes: 0d3008d1a9ae ("rtnetlink: Move ops->validate to rtnl_newlink().")
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>

Thanks for catching!

> ---
> Compile tested only
> ---
>  net/core/rtnetlink.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
> index 194a81e5f608..e269fae2b579 100644
> --- a/net/core/rtnetlink.c
> +++ b/net/core/rtnetlink.c
> @@ -3829,8 +3829,10 @@ static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
>  	}
>  
>  	if (ops) {
> -		if (ops->maxtype > RTNL_MAX_TYPE)
> -			return -EINVAL;
> +		if (ops->maxtype > RTNL_MAX_TYPE) {
> +			ret = -EINVAL;
> +			goto put_ops;
> +		}
>  
>  		if (ops->maxtype && linkinfo[IFLA_INFO_DATA]) {
>  			ret = nla_parse_nested_deprecated(tbs->attr, ops->maxtype,
> -- 
> 2.47.0