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 BEFADC43334 for ; Thu, 9 Jun 2022 18:19:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345335AbiFISS7 (ORCPT ); Thu, 9 Jun 2022 14:18:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36510 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233182AbiFISSz (ORCPT ); Thu, 9 Jun 2022 14:18:55 -0400 Received: from out2.migadu.com (out2.migadu.com [188.165.223.204]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9DF143AE822 for ; Thu, 9 Jun 2022 11:18:52 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1654798731; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=fO4jbpVApVQcfTPwx9gBa9O1ee1UTzsQG3M5HGLfNnA=; b=Xa3doeBqLfHwMDbSeTb4ZiFXvBmIjIofPaa33n/qvrG/uWiPfuEdLm4uM0UENmXHeStFzI 05B2JyJIU0BKhPX6l1OEPU9ljfiSO4uJc8a8Ta+g8lK5davYDlg+I/F1PNsr9pOnGgg1I3 Or3TzC6G5wLjJyGaTo+AhgrnmvED5fw= From: andrey.konovalov@linux.dev To: Andrew Morton Cc: Andrey Konovalov , Marco Elver , Alexander Potapenko , Dmitry Vyukov , Andrey Ryabinin , kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrey Konovalov Subject: [PATCH v2 2/3] mm: introduce clear_highpage_kasan_tagged Date: Thu, 9 Jun 2022 20:18:46 +0200 Message-Id: <4471979b46b2c487787ddcd08b9dc5fedd1b6ffd.1654798516.git.andreyknvl@google.com> In-Reply-To: <1ecaffc0a9c1404d4d7cf52efe0b2dc8a0c681d8.1654798516.git.andreyknvl@google.com> References: <1ecaffc0a9c1404d4d7cf52efe0b2dc8a0c681d8.1654798516.git.andreyknvl@google.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andrey Konovalov Add a clear_highpage_kasan_tagged() helper that does clear_highpage() on a page potentially tagged by KASAN. This helper is used by the following patch. Signed-off-by: Andrey Konovalov --- Changes v1->v2: - Renamed clear_highpage_tagged() to clear_highpage_kasan_tagged(). - Removed extra empty line in clear_highpage_kasan_tagged(). --- include/linux/highmem.h | 10 ++++++++++ mm/page_alloc.c | 8 ++------ 2 files changed, 12 insertions(+), 6 deletions(-) diff --git a/include/linux/highmem.h b/include/linux/highmem.h index 3af34de54330..70b496bbd2d9 100644 --- a/include/linux/highmem.h +++ b/include/linux/highmem.h @@ -243,6 +243,16 @@ static inline void clear_highpage(struct page *page) kunmap_local(kaddr); } +static inline void clear_highpage_kasan_tagged(struct page *page) +{ + u8 tag; + + tag = page_kasan_tag(page); + page_kasan_tag_reset(page); + clear_highpage(page); + page_kasan_tag_set(page, tag); +} + #ifndef __HAVE_ARCH_TAG_CLEAR_HIGHPAGE static inline void tag_clear_highpage(struct page *page) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 66ef8c310dce..76a02255f57c 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1302,12 +1302,8 @@ static void kernel_init_pages(struct page *page, int numpages) /* s390's use of memset() could override KASAN redzones. */ kasan_disable_current(); - for (i = 0; i < numpages; i++) { - u8 tag = page_kasan_tag(page + i); - page_kasan_tag_reset(page + i); - clear_highpage(page + i); - page_kasan_tag_set(page + i, tag); - } + for (i = 0; i < numpages; i++) + clear_highpage_kasan_tagged(page + i); kasan_enable_current(); } -- 2.25.1