From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 00F6CC433F5 for ; Wed, 30 Mar 2022 08:47:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244452AbiC3ItO (ORCPT ); Wed, 30 Mar 2022 04:49:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55568 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242167AbiC3ItE (ORCPT ); Wed, 30 Mar 2022 04:49:04 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B3CB2AC07E; Wed, 30 Mar 2022 01:47:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=wPfcvGoaLqJ0U7znxncjuzYbekQGXK1v+c9yOMjO0Nc=; b=iQO/dpFuFZOMpAC6r3kZDkXiFD gCOsI18AXPCMCis0vlOOS0XOvexSlJNElluMqSL7om/xPbOY+LWG6qGEg0v+BUDT1Reu8d73c0W3i EUw7bTwnVOozHuDLYbKS8tNSAtt1xdoAa03reNvqw6V43sAVgQPv7eMmBVTScyS92r08O+w1LT3rF EqOeJleHn+0orGRolOkd+dM4uURIKkJJynd1Z0i5zllZMm+yf8M8hUOMYOlsXhMVhhpSwlIxCLA43 cuCuY4Fv3onFkpXyYuzQvU/33VcxnOfRK8mWRqnh9V8XCYY0Hw4ootxLPAe9UTIhDO7kuqj39Uy77 UlDuZxFw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=worktop.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nZTy5-006AXR-PI; Wed, 30 Mar 2022 08:46:18 +0000 Received: by worktop.programming.kicks-ass.net (Postfix, from userid 1000) id C0B01986215; Wed, 30 Mar 2022 10:46:15 +0200 (CEST) Date: Wed, 30 Mar 2022 10:46:15 +0200 From: Peter Zijlstra To: Alexander Potapenko Cc: Alexander Viro , Andrew Morton , Andrey Konovalov , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Christoph Hellwig , Christoph Lameter , David Rientjes , Dmitry Vyukov , Eric Dumazet , Greg Kroah-Hartman , Herbert Xu , Ilya Leoshkevich , Ingo Molnar , Jens Axboe , Joonsoo Kim , Kees Cook , Marco Elver , Mark Rutland , Matthew Wilcox , "Michael S. Tsirkin" , Pekka Enberg , Petr Mladek , Steven Rostedt , Thomas Gleixner , Vasily Gorbik , Vegard Nossum , Vlastimil Babka , linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 38/48] objtool: kmsan: list KMSAN API functions as uaccess-safe Message-ID: <20220330084615.GH8939@worktop.programming.kicks-ass.net> References: <20220329124017.737571-1-glider@google.com> <20220329124017.737571-39-glider@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220329124017.737571-39-glider@google.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 29, 2022 at 02:40:07PM +0200, Alexander Potapenko wrote: > KMSAN inserts API function calls in a lot of places (function entries > and exits, local variables, memory accesses), so they may get called > from the uaccess regions as well. That's insufficient. Explain how you did the right thing and made these functions actually safe to be called in this context. > Signed-off-by: Alexander Potapenko > --- > Link: https://linux-review.googlesource.com/id/I242bc9816273fecad4ea3d977393784396bb3c35 > --- > tools/objtool/check.c | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) > > diff --git a/tools/objtool/check.c b/tools/objtool/check.c > index 7c33ec67c4a95..8518eaf05bff0 100644 > --- a/tools/objtool/check.c > +++ b/tools/objtool/check.c > @@ -943,6 +943,25 @@ static const char *uaccess_safe_builtin[] = { > "__sanitizer_cov_trace_cmp4", > "__sanitizer_cov_trace_cmp8", > "__sanitizer_cov_trace_switch", > + /* KMSAN */ > + "kmsan_copy_to_user", > + "kmsan_report", > + "kmsan_unpoison_memory", > + "__msan_chain_origin", > + "__msan_get_context_state", > + "__msan_instrument_asm_store", > + "__msan_metadata_ptr_for_load_1", > + "__msan_metadata_ptr_for_load_2", > + "__msan_metadata_ptr_for_load_4", > + "__msan_metadata_ptr_for_load_8", > + "__msan_metadata_ptr_for_load_n", > + "__msan_metadata_ptr_for_store_1", > + "__msan_metadata_ptr_for_store_2", > + "__msan_metadata_ptr_for_store_4", > + "__msan_metadata_ptr_for_store_8", > + "__msan_metadata_ptr_for_store_n", > + "__msan_poison_alloca", > + "__msan_warning", > /* UBSAN */ > "ubsan_type_mismatch_common", > "__ubsan_handle_type_mismatch", > -- > 2.35.1.1021.g381101b075-goog >