netdev - Re: [net-next PATCH 0/6] ipv4/fib_trie: Cleanups to prepare for introduction of key vector

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: <54F74D74.1050002@redhat.com>
Date:	Wed, 04 Mar 2015 10:22:44 -0800
From:	Alexander Duyck <alexander.h.duyck@...hat.com>
To:	David Miller <davem@...emloft.net>
CC:	netdev@...r.kernel.org
Subject: Re: [net-next PATCH 0/6] ipv4/fib_trie: Cleanups to prepare for introduction
 of key vector

On 03/04/2015 09:53 AM, David Miller wrote:
> From: Alexander Duyck <alexander.h.duyck@...hat.com>
> Date: Wed, 04 Mar 2015 06:51:27 -0800
>
>> If bits can be 32 then idx should be an unsigned long which is 64
>> bits.
> unsigned long is 32-bit on 32-bit platforms

Right, but if unsigned long is 32 bits then usually a pointer is as 
well.  As a result we wouldn't be able to access the upper bits of a 
node with bits == 32 since the size of the tnode would be over 4 * 2^32.

The general idea is the vmalloc should fail when we attempt to allocate 
a bits == 32 tnode on a system w/ only 32b longs.  Then again I think we 
will probably cause a memory corruption on a 32b system since we are 
probably overflowing size_t on the allocation if bits ==32.  I'll have 
to take a look as I believe we are using the offsetof macro and I am not 
sure how that handles a 64b address on a 32b system.

- Alex
--
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