netdev - Re: [RFC][PATCH] ipv6: fix the check when handle RA

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:	Thu, 10 Jul 2014 11:26:50 +0200
From:	Hannes Frederic Sowa <hannes@...hat.com>
To:	roy.qing.li@...il.com
Cc:	netdev@...r.kernel.org, greearb@...delatech.com
Subject: Re: [RFC][PATCH] ipv6: fix the check when handle RA

Hi,

On Do, 2014-07-10 at 16:29 +0800, roy.qing.li@...il.com wrote:
> From: Li RongQing <roy.qing.li@...il.com>
> 
> d9333196572(ipv6:  Allow accepting RA from local IP addresses.) made
> ndisc_router_discovery to skip to handle RA when accept_ra_from_local
> is 0 and saddr of packet is not the device address, in fact, this
> condition should be handled
> 
> Fixes: d9333196572(ipv6:  Allow accepting RA from local IP addresses.)
> Cc: Ben Greear <greearb@...delatech.com>
> Signed-off-by: Li RongQing <roy.qing.li@...il.com>
>  net/ipv6/ndisc.c |    8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
> index a845e3d..e70e805 100644
> --- a/net/ipv6/ndisc.c
> +++ b/net/ipv6/ndisc.c
> @@ -1152,8 +1152,8 @@ static void ndisc_router_discovery(struct sk_buff *skb)
>  	 * accept_ra_from_local is set to true.
>  	 */
>  	if (!(in6_dev->cnf.accept_ra_from_local ||
> -	      ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr,
> -			    NULL, 0))) {
> +	      !ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr,
> +			     NULL, 0))) {

Uh!

Instead of double negotiation can you please write

if (!in6_dev->cnf.accept_ra_from_local &&
    ipv6_chk_addr(...)) {
	printk(...);
	goto skip;
}

Thanks for fixing this, good catch!

Thanks,
Hannes


--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html