[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <20090926204951.424e567e@infradead.org>
Date: Sat, 26 Sep 2009 20:49:51 +0200
From: Arjan van de Ven <arjan@...radead.org>
To: linux-kernel@...r.kernel.org
Cc: torvalds@...ux-foundation.org, mingo@...e.hu
Subject: [PATCH 0/9] Series to make copy_from_user to a stack slot provable
right
[PATCH 0/9] Series to make copy_from_user to a stack slot provable right
This series contains a series of patches that, when applied, make every
copy_from_user() in a make allyesconfig to a (direct) stack slot
provable-by-gcc to have a correct size.
This is useful because if we fix all of these, we can make the non-provable
case an error, as an indication of a possible security hole.
Now the series has 4 types of patches
1) changes where the original code really was missing checks
2) changes where the checks were coded so complex and games were played with
types, that I (and the compiler) couldn't be sure if it was correct or
not
3) changes where we're hitting a small gcc missing optimization, but where
a simplification of the code allows gcc to prove things anyway.
(http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41477 is filed for this)
4) a case in sys_socketcall where Dave Miller and co were very smart in
optimizing the code to the point where it's not reasonable for gcc
to realize the result is ok.
--
Arjan van de Ven Intel Open Source Technology Centre
For development, discussion and tips for power savings,
visit http://www.lesswatts.org
--
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/
Powered by blists - more mailing lists