linux-kernel - Re: [AppArmor 01/41] Pass struct vfsmount to the inode

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sat, 26 May 2007 01:20:50 -0400
From:	Kyle Moffett <mrmacman_g4@....com>
To:	casey@...aufler-ca.com
Cc:	Andreas Gruenbacher <agruen@...e.de>,
	James Morris <jmorris@...ei.org>, linux-kernel@...r.kernel.org,
	linux-security-module@...r.kernel.org,
	linux-fsdevel@...r.kernel.org
Subject: Re: [AppArmor 01/41] Pass struct vfsmount to the inode_create LSM hook

On May 24, 2007, at 14:58:41, Casey Schaufler wrote:
> On Fedora zcat, gzip and gunzip are all links to the same file.  I  
> can imagine (although it is a bit of a stretch) allowing a set of  
> users access to gunzip but not gzip (or the other way around).

That is a COMPLETE straw-man argument.  I can override your "check"  
with this absolutely trivial perl code:

exec { "/usr/bin/gunzip" } "gzip", "-9", "some/file/to.gz";

Pathname-based checks are pretty fundamentally insecure.  If you want  
to protect a "name", then you should tag the "name" with security  
attributes (IE: AppArmor).  On the other hand, if you actually want  
to protect the _data_, then tagging the _name_ is flawed; tag the  
*DATA* instead.

Cheers,
Kyle Moffett

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/