Re: [PATCH v2 3/5] signal: Add unsafe_copy_siginfo_to_user()

From: Christophe Leroy
Date: Mon Sep 13 2021 - 08:59:06 EST

Le 02/09/2021 à 08:54, Christoph Hellwig a écrit :
On Mon, Aug 23, 2021 at 03:35:53PM +0000, Christophe Leroy wrote:
In the same spirit as commit fb05121fd6a2 ("signal: Add
unsafe_get_compat_sigset()"), implement an 'unsafe' version of
copy_siginfo_to_user() in order to use it within user access blocks.

For that, also add an 'unsafe' version of clear_user().

I'm a little worried about all these unsafe helper in powerpc and the
ever increasing scope of the unsafe sections. Can you at least at
powerpc support to objtool to verify them? objtool verifications has
helped to find quite a few bugs in unsafe sections on x86.

Ok, I've started looking at it, I have not found any work at all on objtool for powerpc. I'll see if I can draft something from the ARM64 tentatives.