From patchwork Mon Dec 13 21:51:27 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: andrey.konovalov@linux.dev X-Patchwork-Id: 12674643 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6D743C433EF for ; Mon, 13 Dec 2021 21:56:43 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 34B006B0082; Mon, 13 Dec 2021 16:52:47 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 2FBB16B0083; Mon, 13 Dec 2021 16:52:47 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 19CCE6B0085; Mon, 13 Dec 2021 16:52:47 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0150.hostedemail.com [216.40.44.150]) by kanga.kvack.org (Postfix) with ESMTP id 0B0436B0082 for ; Mon, 13 Dec 2021 16:52:47 -0500 (EST) Received: from smtpin23.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id C3A2188CC2 for ; Mon, 13 Dec 2021 21:52:36 +0000 (UTC) X-FDA: 78914120712.23.B86B02F Received: from out2.migadu.com (out2.migadu.com [188.165.223.204]) by imf26.hostedemail.com (Postfix) with ESMTP id 501AF14000A for ; Mon, 13 Dec 2021 21:52:36 +0000 (UTC) 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=1639432355; 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=TniNgsonCV7N4x8CfBP962yTwJ3ZQbzv223ievd0EoQ=; b=qgWBUnSM2HjTQWnNHG+qKWKL4esKiybqeMZ9plWehZNkgmm+ZI3K4eQpAFQawUNEcKB8M7 Bvp0+OgR6omA8Nzhv+ZHwCaNSzgfHuNZ1I9nNuJjYtJZROS3QYE5GGAm7N0IzKF+MtAKzF fCgA/nKiLou/zWxg31elX1Ll+wQYHEk= From: andrey.konovalov@linux.dev To: Marco Elver , Alexander Potapenko , Andrew Morton Cc: Andrey Konovalov , Dmitry Vyukov , Andrey Ryabinin , kasan-dev@googlegroups.com, linux-mm@kvack.org, Vincenzo Frascino , Catalin Marinas , Will Deacon , Mark Rutland , linux-arm-kernel@lists.infradead.org, Peter Collingbourne , Evgenii Stepanov , linux-kernel@vger.kernel.org, Andrey Konovalov Subject: [PATCH mm v3 08/38] kasan: only apply __GFP_ZEROTAGS when memory is zeroed Date: Mon, 13 Dec 2021 22:51:27 +0100 Message-Id: <95711511a7f88855ba3ed7dde2f2ad23c7b2b02c.1639432170.git.andreyknvl@google.com> In-Reply-To: References: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: andrey.konovalov@linux.dev X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 501AF14000A X-Stat-Signature: xihs5zth5iksoa5o54zb56ax7t7qxf6m Authentication-Results: imf26.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=qgWBUnSM; spf=pass (imf26.hostedemail.com: domain of andrey.konovalov@linux.dev designates 188.165.223.204 as permitted sender) smtp.mailfrom=andrey.konovalov@linux.dev; dmarc=pass (policy=none) header.from=linux.dev X-HE-Tag: 1639432356-134018 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: From: Andrey Konovalov __GFP_ZEROTAGS should only be effective if memory is being zeroed. Currently, hardware tag-based KASAN violates this requirement. Fix by including an initialization check along with checking for __GFP_ZEROTAGS. Signed-off-by: Andrey Konovalov Reviewed-by: Alexander Potapenko --- mm/kasan/hw_tags.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c index 0b8225add2e4..c643740b8599 100644 --- a/mm/kasan/hw_tags.c +++ b/mm/kasan/hw_tags.c @@ -199,11 +199,12 @@ void kasan_alloc_pages(struct page *page, unsigned int order, gfp_t flags) * page_alloc.c. */ bool init = !want_init_on_free() && want_init_on_alloc(flags); + bool init_tags = init && (flags & __GFP_ZEROTAGS); if (flags & __GFP_SKIP_KASAN_POISON) SetPageSkipKASanPoison(page); - if (flags & __GFP_ZEROTAGS) { + if (init_tags) { int i; for (i = 0; i != 1 << order; ++i)