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  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Fri, 10 Dec 2021 13:05:03 -0500
From:   "Theodore Y. Ts'o" <tytso@....edu>
To:     Jia-Ju Bai <baijiaju1990@...il.com>
Cc:     adilger.kernel@...ger.ca, linux-ext4@...r.kernel.org,
        linux-kernel <linux-kernel@...r.kernel.org>
Subject: Re: [BUG] fs: ext4: possible ABBA deadlock in
 ext4_inline_data_truncate() and ext4_punch_hole()

On Fri, Dec 10, 2021 at 10:03:37AM +0800, Jia-Ju Bai wrote:
> 
> Thank you very much for the detailed explanation!
> I will improve my static analysis tool for this point.

I'm not sure it will be possible to programatically detect why the
ABBA deadlock isn't possible without having the static analyzer having
a semantic understanding how the code works (so it can understand that
that code path which leads to the ABBA deadlock won't get executed).

It may very well be that being able to understand why the ABBA
deadlock can't happen in that case is equivalent to solving the
halting problem.  But if you do come up with a clever way of improving
your static analysis tool, I'll be excited to see it!

Cheers,

					- Ted

Powered by blists - more mailing lists