Subject: Re: [PATCH] devlink: fix potential memort leak
To: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jiri Pirko <jiri@mellanox.com>
References: <1496580592-13659-1-git-send-email-yanhaishuang@cmss.chinamobile.com>
Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org
From: Arkadi Sharshevsky <arkadis@mellanox.com>
Message-ID: <1c80b8da-3f00-48de-f89b-75cf18eebf5d@mellanox.com>
Date: Sun, 4 Jun 2017 16:07:43 +0300
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101
 Thunderbird/45.8.0
MIME-Version: 1.0
In-Reply-To: <1496580592-13659-1-git-send-email-yanhaishuang@cmss.chinamobile.com>
Content-Type: text/plain; charset=windows-1252
Content-Transfer-Encoding: 7bit
SpamDiagnosticOutput: 1:99
SpamDiagnosticMetadata: NSPM
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Jun 2017 13:08:00.8294 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB6PR0501MB2455
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 987
Lines: 32


On 06/04/2017 03:49 PM, Haishuang Yan wrote:
> We must free allocated skb when genlmsg_put() return fails.
> 
> Fixes: 1555d204e743 ("devlink: Support for pipeline debug (dpipe)")
> Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
> ---
>  net/core/devlink.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/net/core/devlink.c b/net/core/devlink.c
> index b0b87a2..70b69c6 100644
> --- a/net/core/devlink.c
> +++ b/net/core/devlink.c
> @@ -1680,8 +1680,10 @@ static int devlink_dpipe_tables_fill(struct genl_info *info,
>  
>  	hdr = genlmsg_put(skb, info->snd_portid, info->snd_seq,
>  			  &devlink_nl_family, NLM_F_MULTI, cmd);
> -	if (!hdr)
> +	if (!hdr) {
> +		nlmsg_free(skb);
>  		return -EMSGSIZE;
> +	}
>  
>  	if (devlink_nl_put_handle(skb, devlink))
>  		goto nla_put_failure;
> 

Thanks! I think it a bit better to set the err and goto
down the error path below (only nlmsg_free()). Headrs_fill()
also suffers from this problem.