From patchwork Mon Dec 6 21:43:42 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: 12694990 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 039C3C433F5 for ; Mon, 6 Dec 2021 21:46:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=b8Yc3L1lYAY+YEJ6rULjVhdc8fuRZ2Lm/OOKvsyySNU=; b=Ncz1vO+tcNukV/ TMLu30pUkR36cKMVhaccjXQ7ESaP1r4iVPVhVV5bDF0x+7l/CpxdCJonVNrz25zmhNyx8p2QI3uUP DOhu1Nn3uzRQgEkTfroKsOF8IWfJnGc5qyF2MaWTsqBvphoChG4NIO5bE2yvjXXotJLPUeiBzObU7 9BciuCePHdyd9zrYuJfTzMgYk7GGPkXubaoUQQEf8p8Ul5Kq9WJbTpToGVAS14rHmSRdiN4lhHL8A FMzRQuqtuvGWEyzJyDybT7hXKKn++ipAyEZsEZy43rvMckjn7b4LbVdY9JP7U7krc7N6gEIzW1ZCV N+bb7bPJeHvKc69tNMsQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1muLmy-005yoB-U6; Mon, 06 Dec 2021 21:44:50 +0000 Received: from out2.migadu.com ([188.165.223.204]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1muLmX-005ygH-K1 for linux-arm-kernel@lists.infradead.org; Mon, 06 Dec 2021 21:44:23 +0000 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=1638827060; 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=CDfDFpOAo922pZ0chQAMNz9tzdyiLXIp8K+CHBQuOYo=; b=gbVFChOrfx9TbOhvcPZkQHwrv+Btc9qpYHzIIr39UxSGbk4K6PLE6TQJhV4xwYqedXDtA1 eteMfFOiRbRw6/xRRY7CVQvzYoJOgTnaN2FZmwfaA1uo8R8M0hgv1WVY+xbvnlc0QnCDgV qxPAc3KLVfumtS7wA8rwFlkCTln8M8o= From: andrey.konovalov@linux.dev To: Marco Elver , Alexander Potapenko , Vincenzo Frascino , Catalin Marinas , Peter Collingbourne Cc: Andrey Konovalov , Dmitry Vyukov , Andrey Ryabinin , kasan-dev@googlegroups.com, Andrew Morton , linux-mm@kvack.org, Will Deacon , Mark Rutland , linux-arm-kernel@lists.infradead.org, Evgenii Stepanov , linux-kernel@vger.kernel.org, Andrey Konovalov Subject: [PATCH v2 05/34] kasan, page_alloc: init memory of skipped pages on free Date: Mon, 6 Dec 2021 22:43:42 +0100 Message-Id: In-Reply-To: References: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211206_134421_855601_B7BF7DDA X-CRM114-Status: GOOD ( 12.73 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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. Fixes: 7a3b83537188 ("kasan: use separate (un)poison implementation for integrated init") Signed-off-by: Andrey Konovalov --- 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 15f76bc1fa3e..2ada09a58e4b 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1360,11 +1360,16 @@ 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