netdev - Re: [PATCH net] ethtool: fix missing NLM_F

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Wed, 5 May 2021 23:09:19 +0200
From:   Michal Kubecek <mkubecek@...e.cz>
To:     Fernando Fernandez Mancera <ffmancera@...eup.net>
Cc:     netdev@...r.kernel.org, atenart@...nel.org
Subject: Re: [PATCH net] ethtool: fix missing NLM_F_MULTI flag when dumping

On Wed, May 05, 2021 at 12:47:14AM +0200, Fernando Fernandez Mancera wrote:
> When dumping the ethtool information from all the interfaces, the
> netlink reply should contain the NLM_F_MULTI flag. This flag allows
> userspace tools to identify that multiple messages are expected.
> 
> Link: https://bugzilla.redhat.com/1953847
> Fixes: 365f9ae ("ethtool: fix genlmsg_put() failure handling in ethnl_default_dumpit()")

For the record, the issue was not introduced by this commit, this commit
only moved the genlmsg_put() call from ethnl_default_dumpit() into
ethnl_default_dump_one() but genlmsg_put() was called with zero flags
since the code was introduced by commit 728480f12442 ("ethtool: default
handlers for GET requests").

But as the patch has been applied already, it doesn't matter any more.

Michal

> Signed-off-by: Fernando Fernandez Mancera <ffmancera@...eup.net>
> ---
>  net/ethtool/netlink.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
> index 290012d0d11d..88d8a0243f35 100644
> --- a/net/ethtool/netlink.c
> +++ b/net/ethtool/netlink.c
> @@ -387,7 +387,8 @@ static int ethnl_default_dump_one(struct sk_buff *skb, struct net_device *dev,
>  	int ret;
>  
>  	ehdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
> -			   &ethtool_genl_family, 0, ctx->ops->reply_cmd);
> +			   &ethtool_genl_family, NLM_F_MULTI,
> +			   ctx->ops->reply_cmd);
>  	if (!ehdr)
>  		return -EMSGSIZE;
>  
> -- 
> 2.20.1
>