netdev - Re: [PATCH net] net/route: remove ip route rtm_src_len, rtm_dst

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]

Message-ID: <20200113063900.GI2159@dhcp-12-139.nay.redhat.com>
Date:   Mon, 13 Jan 2020 14:39:00 +0800
From:   Hangbin Liu <liuhangbin@...il.com>
To:     David Ahern <dsahern@...il.com>
Cc:     netdev@...r.kernel.org,
        Jakub Kicinski <jakub.kicinski@...ronome.com>,
        "David S . Miller" <davem@...emloft.net>
Subject: Re: [PATCH net] net/route: remove ip route rtm_src_len, rtm_dst_len
 valid check

On Sat, Jan 11, 2020 at 10:38:23AM -0700, David Ahern wrote:
> On 1/10/20 6:18 PM, Hangbin Liu wrote:
> > On Fri, Jan 10, 2020 at 02:48:03PM -0700, David Ahern wrote:
> >> On 1/10/20 1:24 AM, Hangbin Liu wrote:
> >>> In patch set e266afa9c7af ("Merge branch
> >>> 'net-use-strict-checks-in-doit-handlers'") we added a check for
> >>> rtm_src_len, rtm_dst_len, which will cause cmds like
> >>> "ip route get 192.0.2.0/24" failed.
> >>
> >> kernel does not handle route gets for a range. Any output is specific to
> >> the prefix (192.0.2.0 in your example) so it seems to me the /24 request
> >> should fail.
> >>
> > 
> > OK, so we should check all the range field if NETLINK_F_STRICT_CHK supplied,
> > like the following patch, right?
> 
> a dst_len / src_len of 32 (or 128 for v6) is ok. It still means only the
> prefix is used for the route get. That's why it was coded this way as
> part of the change for stricter checking.
> 

Ah, I see now. Thanks for the interpretation.

Regards
Hangbin