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 X-Spam-Level: X-Spam-Status: No, score=-23.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B5BECC433E0 for ; Fri, 5 Mar 2021 17:05:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8E66C64F51 for ; Fri, 5 Mar 2021 17:05:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231426AbhCERFM (ORCPT ); Fri, 5 Mar 2021 12:05:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39498 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231327AbhCEREj (ORCPT ); Fri, 5 Mar 2021 12:04:39 -0500 Received: from mail-pg1-x52f.google.com (mail-pg1-x52f.google.com [IPv6:2607:f8b0:4864:20::52f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0E0E9C061574 for ; Fri, 5 Mar 2021 09:04:39 -0800 (PST) Received: by mail-pg1-x52f.google.com with SMTP id x29so1792769pgk.6 for ; Fri, 05 Mar 2021 09:04:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=VCvImFx+wjxWiBbU2aABnmv0wEUTxntHCJc3sPTuzt0=; b=dXaqm+VxNg2RViHBaZ0HAsG7Ly1wCaEY1w/LvaKxbzoEWPkTUmsgeCynvu6OmZIeoy gNawnUoFWo84SIk7OsyslEzNAMqD9mTawzcbJcZUIibf+9FOhJ2RN7XwByJhlaFrJaaf VnRMSyLVTkrBlB3qRagyt263D71B8YXt7MAMiTTfTetWqMEbLqdsv5meS2q1KmsjTidz UCZcOWy16Uo7UB2JcmkQkFUA5d4BU5fhQWBN2LnyOgtXl9kPfg3a10BGFQt2wQBYwQbO gZyToCRDOjSZz+ZWolm3WfPAi0aFwfti1SHI1WehYDHKour6MlASvLR9WUc6XaH7e4H2 Yasg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=VCvImFx+wjxWiBbU2aABnmv0wEUTxntHCJc3sPTuzt0=; b=CDMSQb6h2s1btprzF216XnCQhOjYyi9us9WxhNPgMUU2HyTFMdcBv+fIwUNtODFasQ YFywf1ElCJkl2RyLZXMsYEgKDOs5G2WEzpkRFQmCVDt5Z9lTUyebqydbf6djMc76igoF DXCo2QJp9WcR/WCmgHACLZlvfzcv2oTSehogHqIO3r30ui6RbgmSS32+9oV8FIsIOR53 F8mXXDEm85Us7x9thDkfWbggdtyImuDSlp8EXOyCTAwjdbVuNaQEuyy6iW4okQTLx7EE FSpJpSJYiCbowqIUYGka/ll730OQQwixKTJPxrD0P5lk/9R3+q93MFZ4SOcL5RbhToBo B6qA== X-Gm-Message-State: AOAM531smfTjhQE19e/IYCYxZ3lTq3KC7RVi3xMKcNisDKLhjNGaXPzq Pk4Gy6D/T7/Oz3X87BQ6m//34Th4ehSlBJlYCnZmvQ== X-Google-Smtp-Source: ABdhPJxAX3ppZx/J43oBs600LSSxe6ehgcl1hfWycwnFOzRGOHGJWpPGSwRgxxf0J1SX3/CfsvapDRc/SDafh54WYOw= X-Received: by 2002:a62:38c8:0:b029:1ef:21ba:aba3 with SMTP id f191-20020a6238c80000b02901ef21baaba3mr8126629pfa.24.1614963878391; Fri, 05 Mar 2021 09:04:38 -0800 (PST) MIME-Version: 1.0 References: <1aa83e48627978de8068d5e3314185f3a0d7a849.1614302398.git.andreyknvl@google.com> In-Reply-To: <1aa83e48627978de8068d5e3314185f3a0d7a849.1614302398.git.andreyknvl@google.com> From: Andrey Konovalov Date: Fri, 5 Mar 2021 18:04:27 +0100 Message-ID: Subject: Re: [PATCH] kasan, mm: fix crash with HW_TAGS and DEBUG_PAGEALLOC To: Andrew Morton Cc: Catalin Marinas , Will Deacon , Vincenzo Frascino , Dmitry Vyukov , Andrey Ryabinin , Alexander Potapenko , Marco Elver , Peter Collingbourne , Evgenii Stepanov , Branislav Rankov , Kevin Brodsky , Christoph Hellwig , kasan-dev , Linux ARM , Linux Memory Management List , LKML Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 26, 2021 at 2:25 AM Andrey Konovalov wrote: > > Currently, kasan_free_nondeferred_pages()->kasan_free_pages() is called > after debug_pagealloc_unmap_pages(). This causes a crash when > debug_pagealloc is enabled, as HW_TAGS KASAN can't set tags on an > unmapped page. > > This patch puts kasan_free_nondeferred_pages() before > debug_pagealloc_unmap_pages(). > > Besides fixing the crash, this also makes the annotation order consistent > with debug_pagealloc_map_pages() preceding kasan_alloc_pages(). > > Signed-off-by: Andrey Konovalov > --- > mm/page_alloc.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index c89e7b107514..54bc237fd319 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -1311,10 +1311,14 @@ static __always_inline bool free_pages_prepare(struct page *page, > */ > arch_free_page(page, order); > > - debug_pagealloc_unmap_pages(page, 1 << order); > - > + /* > + * With hardware tag-based KASAN, memory tags must be set > + * before unmapping the page with debug_pagealloc. > + */ > kasan_free_nondeferred_pages(page, order, fpi_flags); Looking at this again, I think we need to move kasan_() callback above arch_free_page(), as that can also make the page unavailable. I'll send v2. 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Fri, 05 Mar 2021 09:04:38 -0800 (PST) MIME-Version: 1.0 References: <1aa83e48627978de8068d5e3314185f3a0d7a849.1614302398.git.andreyknvl@google.com> In-Reply-To: <1aa83e48627978de8068d5e3314185f3a0d7a849.1614302398.git.andreyknvl@google.com> From: Andrey Konovalov Date: Fri, 5 Mar 2021 18:04:27 +0100 Message-ID: Subject: Re: [PATCH] kasan, mm: fix crash with HW_TAGS and DEBUG_PAGEALLOC To: Andrew Morton Cc: Catalin Marinas , Will Deacon , Vincenzo Frascino , Dmitry Vyukov , Andrey Ryabinin , Alexander Potapenko , Marco Elver , Peter Collingbourne , Evgenii Stepanov , Branislav Rankov , Kevin Brodsky , Christoph Hellwig , kasan-dev , Linux ARM , Linux Memory Management List , LKML Content-Type: text/plain; charset="UTF-8" X-Stat-Signature: n3pt4jzhf1i8fact13hb7n9i8spbg4zh X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: C687FA0049C7 Received-SPF: none (google.com>: No applicable sender policy available) receiver=imf24; identity=mailfrom; envelope-from=""; helo=mail-pg1-f177.google.com; client-ip=209.85.215.177 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1614963877-722882 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Feb 26, 2021 at 2:25 AM Andrey Konovalov wrote: > > Currently, kasan_free_nondeferred_pages()->kasan_free_pages() is called > after debug_pagealloc_unmap_pages(). This causes a crash when > debug_pagealloc is enabled, as HW_TAGS KASAN can't set tags on an > unmapped page. > > This patch puts kasan_free_nondeferred_pages() before > debug_pagealloc_unmap_pages(). > > Besides fixing the crash, this also makes the annotation order consistent > with debug_pagealloc_map_pages() preceding kasan_alloc_pages(). > > Signed-off-by: Andrey Konovalov > --- > mm/page_alloc.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index c89e7b107514..54bc237fd319 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -1311,10 +1311,14 @@ static __always_inline bool free_pages_prepare(struct page *page, > */ > arch_free_page(page, order); > > - debug_pagealloc_unmap_pages(page, 1 << order); > - > + /* > + * With hardware tag-based KASAN, memory tags must be set > + * before unmapping the page with debug_pagealloc. > + */ > kasan_free_nondeferred_pages(page, order, fpi_flags); Looking at this again, I think we need to move kasan_() callback above arch_free_page(), as that can also make the page unavailable. I'll send v2. 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a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=VCvImFx+wjxWiBbU2aABnmv0wEUTxntHCJc3sPTuzt0=; b=O/H8AKCvz6JlJckURGSomf/9mpdUtXyKNS+96R0nCYlsnTOGR3EeY9LYw5f87jTIsD QuWDlmqvtKUv56pnIzfmm9r0Ohf0VAgKJB6tZYi8UsHIigG8HqGGKGp2jVKsYHqebFuF uYBivKTmTf0Uok5fiBGEk0rNNTOR0M9RvTn+0nTLaZpAbvhcA1K4zY04DwQTk8SpTl9F q5qPJew7U+vCpsEubGfnlVMVMRQOOuXj0qFm6AuejuUoJ2JHd0EI9UMCdF+mP8UIe+tE 4ITye6z6lxhqAW06Uw1wHWOB18qH7fkje7nimSd1h2A2dyd3Wq12BZCNejDbKK9ZBKb5 mdKA== X-Gm-Message-State: AOAM53304Um4DDIpTKpD2Ytcqyw8iqJ/T0wujElePSODTdDfyT/Ozrem UCifo5BEkB+klVYLhj3lmD3VI+/aqQweTagXBX/cog== X-Google-Smtp-Source: ABdhPJxAX3ppZx/J43oBs600LSSxe6ehgcl1hfWycwnFOzRGOHGJWpPGSwRgxxf0J1SX3/CfsvapDRc/SDafh54WYOw= X-Received: by 2002:a62:38c8:0:b029:1ef:21ba:aba3 with SMTP id f191-20020a6238c80000b02901ef21baaba3mr8126629pfa.24.1614963878391; Fri, 05 Mar 2021 09:04:38 -0800 (PST) MIME-Version: 1.0 References: <1aa83e48627978de8068d5e3314185f3a0d7a849.1614302398.git.andreyknvl@google.com> In-Reply-To: <1aa83e48627978de8068d5e3314185f3a0d7a849.1614302398.git.andreyknvl@google.com> From: Andrey Konovalov Date: Fri, 5 Mar 2021 18:04:27 +0100 Message-ID: Subject: Re: [PATCH] kasan, mm: fix crash with HW_TAGS and DEBUG_PAGEALLOC To: Andrew Morton Cc: Catalin Marinas , Will Deacon , Vincenzo Frascino , Dmitry Vyukov , Andrey Ryabinin , Alexander Potapenko , Marco Elver , Peter Collingbourne , Evgenii Stepanov , Branislav Rankov , Kevin Brodsky , Christoph Hellwig , kasan-dev , Linux ARM , Linux Memory Management List , LKML X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210305_170440_273253_3EAAE49F X-CRM114-Status: GOOD ( 18.71 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Feb 26, 2021 at 2:25 AM Andrey Konovalov wrote: > > Currently, kasan_free_nondeferred_pages()->kasan_free_pages() is called > after debug_pagealloc_unmap_pages(). This causes a crash when > debug_pagealloc is enabled, as HW_TAGS KASAN can't set tags on an > unmapped page. > > This patch puts kasan_free_nondeferred_pages() before > debug_pagealloc_unmap_pages(). > > Besides fixing the crash, this also makes the annotation order consistent > with debug_pagealloc_map_pages() preceding kasan_alloc_pages(). > > Signed-off-by: Andrey Konovalov > --- > mm/page_alloc.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index c89e7b107514..54bc237fd319 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -1311,10 +1311,14 @@ static __always_inline bool free_pages_prepare(struct page *page, > */ > arch_free_page(page, order); > > - debug_pagealloc_unmap_pages(page, 1 << order); > - > + /* > + * With hardware tag-based KASAN, memory tags must be set > + * before unmapping the page with debug_pagealloc. > + */ > kasan_free_nondeferred_pages(page, order, fpi_flags); Looking at this again, I think we need to move kasan_() callback above arch_free_page(), as that can also make the page unavailable. I'll send v2. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel