linux-ext4 - Re: [PATCH 1/1] ext4: fix potential negative array index in do

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, 29 Jul 2020 21:48:35 -0400
From:   tytso@....edu
To:     Eric Sandeen <sandeen@...hat.com>
Cc:     "linux-ext4@...r.kernel.org" <linux-ext4@...r.kernel.org>
Subject: Re: [PATCH 1/1] ext4: fix potential negative array index in
 do_split()

On Wed, Jun 17, 2020 at 02:19:04PM -0500, Eric Sandeen wrote:
> If for any reason a directory passed to do_split() does not have enough
> active entries to exceed half the size of the block, we can end up
> iterating over all "count" entries without finding a split point.
> 
> In this case, count == move, and split will be zero, and we will
> attempt a negative index into map[].
> 
> Guard against this by detecting this case, and falling back to
> split-to-half-of-count instead; in this case we will still have
> plenty of space (> half blocksize) in each split block.
> 
> Fixes: ef2b02d3e617 ("ext34: ensure do_split leaves enough free space in both blocks")
> Signed-off-by: Eric Sandeen <sandeen@...hat.com>

Thanks, applied.

						- Ted