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 07B07C433FE for ; Wed, 27 Apr 2022 07:16:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1358717AbiD0HSv (ORCPT ); Wed, 27 Apr 2022 03:18:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51998 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1358692AbiD0HSi (ORCPT ); Wed, 27 Apr 2022 03:18:38 -0400 Received: from mout.kundenserver.de (mout.kundenserver.de [212.227.126.134]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4CABB18361; Wed, 27 Apr 2022 00:15:17 -0700 (PDT) Received: from mail-yb1-f180.google.com ([209.85.219.180]) by mrelayeu.kundenserver.de (mreue010 [213.165.67.97]) with ESMTPSA (Nemesis) id 1MJVU0-1nPjat3wIS-00JqT6; Wed, 27 Apr 2022 09:15:16 +0200 Received: by mail-yb1-f180.google.com with SMTP id w17so1715863ybh.9; Wed, 27 Apr 2022 00:15:15 -0700 (PDT) X-Gm-Message-State: AOAM533E2K1UKjQFKhxNn/wdImyAEmBaafMaXYWOvCMulOdDVFdC9ijE Zm/D+8CvgAwimat2r9gkZmpVLphVqGAuYeO5QqQ= X-Google-Smtp-Source: ABdhPJwaD1kOWmwPG8YXCJoPZvqoD54e+nnssat4O6xYNRUCaG64TDt/4SOl6wpW8DE+BePexx2QnPchQt4gdqTD0N8= X-Received: by 2002:a25:c604:0:b0:645:d969:97a7 with SMTP id k4-20020a25c604000000b00645d96997a7mr20381066ybf.134.1651043704287; Wed, 27 Apr 2022 00:15:04 -0700 (PDT) MIME-Version: 1.0 References: <20220426164315.625149-1-glider@google.com> <20220426164315.625149-6-glider@google.com> In-Reply-To: <20220426164315.625149-6-glider@google.com> From: Arnd Bergmann Date: Wed, 27 Apr 2022 09:14:48 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v3 05/46] x86: asm: instrument usercopy in get_user() and __put_user_size() 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 , Peter Zijlstra , Petr Mladek , Steven Rostedt , Thomas Gleixner , Vasily Gorbik , Vegard Nossum , Vlastimil Babka , kasan-dev , Linux-MM , linux-arch , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" X-Provags-ID: V03:K1:X825Nodsp/CILpTFtsaUc0WqmlMiOdJWzevNH4xFQGBXKufG+O9 DShGp8pTm7eRlyTooBJO8zwF/De5Wf7IvyAFn0Gog4gPQ0f+3onWS2ZWVKVgf1sP3OD7cjc aaGMv0hF/PZbLWkRZ+lSqMbnh+dJqCqfF2O0Zlas+maOkYQrJJO0FBS8VcUi3fAQEkvtJFo jetBEutOri6z3WtTCzMPA== X-UI-Out-Filterresults: notjunk:1;V03:K0:12eyt6cQDXI=:8QIbwNy4LP8WPQWFVHlWHU e/YPQYO3s12X/fDA6oxZ3hCKFlp8qR04u+RkK57XAvRjtYAEq517/fuEjA4PCWy1Hwwvl1F6c ++XWcZLbnjCh7SXkZ1SJ3iUME/7yBmjptkHCKmJQ+5pepHcGs2eDvI+Cqqaegt2fxRw4XZCHt D2vyr62TtToYwOeSUI02/gf859OzVFMs4Az960I4nFiYQrP1DdlePOVR5XFy1QRdRTSU1M7cT 0db8mDjL1z8ZStXuQOrYp3JXkTDwzXHC6TnyEQR7krnmLXHANvfvncE3TGk8DocG+3dtovCEZ cfIj+mcbeDgsqmS3LeW9VX19CBY5QYrZxbEJWIeL+UyizIEGAPjAOcexTrgVP2Z8NBen2JaDs A120nq7iJmfagKAeaATAF414EqqkCHiUlIPFaEdyXPN+F4HL13k+iRfkyw4zf0HGYUI0oQuCR 6nuVEiKFHVgXMH41Gq8711UNohSjWfVr853Csiz6D9HW30zTrqMD4p5cCCGAX2/LnpdJE+rT6 1ZsVA46LEeQo4k2wIcpvjnkpUqGcxwJLj+Fk+GxkTFrORaFqQJcYes/QsTFO+AcOo3wQBoxEC wYGAdehiyGui/UMvXkU5MB55PlzlytpjDsH0XxsRs5me29OsZKqPqxWXOSO7/okvPpiiQtpD+ b514fgcGooNVehZcW1LGBXB4I+Gz9e4Q8HiunEueeWS72w/ZmmGPLjbiebCsmmDzx+X8Mdz7U 0DY8Kb1oboqDlOAtOCtqF8b/fELc0/AgA/QjMacS0u8Lp/ZrFQIyhfcE95l0AwVs7octblUmf XjfsqZIGo0NeODzJASPK3SVFrhg6R4kjIloqCIVOOzAHHAvGD0= Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 26, 2022 at 6:42 PM Alexander Potapenko wrote: > @@ -99,11 +100,13 @@ extern int __get_user_bad(void); > int __ret_gu; \ > register __inttype(*(ptr)) __val_gu asm("%"_ASM_DX); \ > __chk_user_ptr(ptr); \ > + instrument_copy_from_user_before((void *)&(x), ptr, sizeof(*(ptr))); \ > asm volatile("call __" #fn "_%P4" \ > : "=a" (__ret_gu), "=r" (__val_gu), \ > ASM_CALL_CONSTRAINT \ > : "0" (ptr), "i" (sizeof(*(ptr)))); \ > (x) = (__force __typeof__(*(ptr))) __val_gu; \ > + instrument_copy_from_user_after((void *)&(x), ptr, sizeof(*(ptr)), 0); \ Isn't "ptr" the original pointer here? I think what happened with the reported warning is that you get one output line for every instance this is used in. There should probably be a __auto_type __ptr = (ptr); at the beginning of the macro to ensure that 'ptr' is only evaluated once. >>> arch/x86/kernel/signal.c:360:9: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected void [noderef] __user *to @@ got unsigned long long [usertype] * @@ It would also make sense to add the missing __user annotation in this line, but I suspect there are others like it in drivers. Arnd