From patchwork Mon Jan 24 18:02:13 2022 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: 12722650 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 B09DCC433EF for ; Mon, 24 Jan 2022 18:03:02 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 6010B6B009C; Mon, 24 Jan 2022 13:02:59 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 5AF2B6B00A3; Mon, 24 Jan 2022 13:02:59 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 49DA46B00AB; Mon, 24 Jan 2022 13:02:59 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0239.hostedemail.com [216.40.44.239]) by kanga.kvack.org (Postfix) with ESMTP id 3A07E6B009C for ; Mon, 24 Jan 2022 13:02:59 -0500 (EST) Received: from smtpin20.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id E043418404110 for ; Mon, 24 Jan 2022 18:02:58 +0000 (UTC) X-FDA: 79065951636.20.65D35BE Received: from out0.migadu.com (out0.migadu.com [94.23.1.103]) by imf10.hostedemail.com (Postfix) with ESMTP id 733C6C0068 for ; Mon, 24 Jan 2022 18:02:58 +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=1643047377; 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=lu+d0FvmlGAoYbgcSnAcHnve/JGZrRKgqG6H2fXAm3E=; b=jk1sGMKwhwoZgx3UbKB/QI1h3DEwu01knIbZzdZW+9BQ1CAv9uVk/0kNprUvOZwmzqPWVh oIr5aVYPe4721mJRO4psY0m5/WXFgd80rBHDJYkiFvOTd47C7rev723tpFZDGqzEXSdHgP WZMkZakZustuhHBV37ABcRHukwEYlKU= 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, 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 v6 05/39] kasan, page_alloc: init memory of skipped pages on free Date: Mon, 24 Jan 2022 19:02:13 +0100 Message-Id: <1d97df75955e52727a3dc1c4e33b3b50506fc3fd.1643047180.git.andreyknvl@google.com> In-Reply-To: References: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev X-Rspamd-Queue-Id: 733C6C0068 X-Stat-Signature: sey46pafmcgm7hk5t7s1zmw4fg67irs6 Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=jk1sGMKw; spf=pass (imf10.hostedemail.com: domain of andrey.konovalov@linux.dev designates 94.23.1.103 as permitted sender) smtp.mailfrom=andrey.konovalov@linux.dev; dmarc=pass (policy=none) header.from=linux.dev X-Rspamd-Server: rspam01 X-HE-Tag: 1643047378-663434 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 Since commit 7a3b83537188 ("kasan: use separate (un)poison implementation for integrated init"), when all init, kasan_has_integrated_init(), and skip_kasan_poison are true, free_pages_prepare() doesn't initialize the page. This is wrong. Fix it by remembering whether kasan_poison_pages() performed initialization, and call kernel_init_free_pages() if it didn't. Reordering kasan_poison_pages() and kernel_init_free_pages() is OK, since kernel_init_free_pages() can handle poisoned memory. Signed-off-by: Andrey Konovalov --- Changes v2->v3: - Drop Fixes tag, as the patch won't cleanly apply to older kernels anyway. The commit is mentioned in the patch description. Changes v1->v2: - Reorder kasan_poison_pages() and free_pages_prepare() in this patch instead of doing it in the previous one. --- mm/page_alloc.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 60bc838a4d85..f994fd68e3b1 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1375,11 +1375,16 @@ static __always_inline bool free_pages_prepare(struct page *page, * With hardware tag-based KASAN, memory tags must be set before the * page becomes unavailable via debug_pagealloc or arch_free_page. */ - if (init && !kasan_has_integrated_init()) - kernel_init_free_pages(page, 1 << order); - if (!skip_kasan_poison) + if (!skip_kasan_poison) { kasan_poison_pages(page, order, init); + /* Memory is already initialized if KASAN did it internally. */ + if (kasan_has_integrated_init()) + init = false; + } + if (init) + kernel_init_free_pages(page, 1 << order); + /* * arch_free_page() can make the page's contents inaccessible. s390 * does this. So nothing which can access the page's contents should