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=-10.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 1A1D3C433E0 for ; Thu, 25 Jun 2020 05:26:53 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BF74120789 for ; Thu, 25 Jun 2020 05:26:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.ozlabs.org header.i=@lists.ozlabs.org header.b="OcSOxqCD"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=aol.com header.i=@aol.com header.b="q+FLrgcN" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BF74120789 Authentication-Results: mail.kernel.org; dmarc=pass (p=none dis=none) header.from=lists.ozlabs.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linux-erofs-bounces+linux-erofs=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 49spRH0bXRzDqjh for ; Thu, 25 Jun 2020 15:26:51 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=lists.ozlabs.org; s=201707; t=1593062811; bh=mIUWCHo0Dk4ZqEX3jZySRHiG+x64jbzUoBWINYYMar0=; h=To:Subject:Date:References:List-Id:List-Unsubscribe:List-Archive: List-Post:List-Help:List-Subscribe:From:Reply-To:Cc:From; b=OcSOxqCD6Z64tkqEicnZvasC8JAQ3zEKk/tft9IDDUVKZwJlhmwzFSHTVR4DSyLb9 NwBiOEt83Kztn+Fm21WtJiSJ1GYDNDNAtkdHyLmmlI7CHq07soKmv2zCu9eWjeSRfX TRf0U0g0gMl8XDIdHOxokEKDM00/0d5HC2+ZO7yfpRev139qJG89pfw3oVXkz5OWpm I7h/C++QSRu0vkppK8365wm9rLLJutwoJuWjX1AMEx9pH1iGWMY89StsyVfarB6vbC 0xCe4cS6Ncsun52uP1+gadVRUoNeuVg49KH2LJwEFbjNdSMeLzCP1R4nrXa/XV7Ppv VE4ddEezmlzuw== Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=aol.com (client-ip=98.137.68.32; helo=sonic308-8.consmr.mail.gq1.yahoo.com; envelope-from=hsiangkao@aol.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=reject dis=none) header.from=aol.com Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=aol.com header.i=@aol.com header.a=rsa-sha256 header.s=a2048 header.b=q+FLrgcN; dkim-atps=neutral Received: from sonic308-8.consmr.mail.gq1.yahoo.com (sonic308-8.consmr.mail.gq1.yahoo.com [98.137.68.32]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 49spR61CjBzDqgb for ; Thu, 25 Jun 2020 15:26:41 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=aol.com; s=a2048; t=1593062794; bh=UI3MnVRcoC7IXe6/MF3z2voS16XTSftvJq41/v0i0mQ=; h=From:To:Cc:Subject:Date:References:From:Subject; b=q+FLrgcNq9vG8GAxW9nvdywce0SSUTQus1YoFMCEPcxjO6ebYukowjfltl7oQomoc5Q7LiaIOiDNd2MbVxtmY6r2Vftgmt1bvLeTlw2aguYVrBdDFUHF8fQ9kig6+MNcu82R9zTlLeEZz+COaVqx+9NO+8NclLcOR+wVu8cPDeS8KNhsZTkpnzxkujL2P/yz+CaWHvC9wj9lpE0XM/rWY8vw6b+csDmYBg34U8pxPnIgWwJYtyMSsQO45LBj5DVayy8OAJmJEDxOZvVWjGkWiRXK9Ye6xDN5n018oJfbxnnTXn0mw64rBVDLbtqVGkxWc+g1/bY4kC7bkxtl6VDSMg== X-YMail-OSG: bsdlrlgVM1mkmtWAtBgP9cd7AhcmSERQIEcd2YkdBf.6gO4emVzjvB2dLmUFp8r cjny56dghxTfkipUFC6.qaE301sz9IPqjVuRndFGBZ8mBVdcD2Iqf3SWeqdGxbpwl.I77lAhGc_B LQ9naH_UKJYbWqZLqrDXMK3tYqfwT43G4iqxmVkOGkEGPUfL4I2JSj3hpZgNo07Ec2QrgPLRpM2A NRcxZ5811BcyCae3uFFyxKjyt3SvNkbY0pH6KiFo_RbwfchbeABwU0mIZ46SToRQnduLM5ZcXD3I GFEi0uAMe5KZ52pCUi7E0zOTexz4nP6WLcie1bGmJqb1YmmnOw8uUiy4xihO6M3lpF3_.K8_vnhw 1UFrUBXJ0Bwv_b8CQG_RMhWC99KIkNr6NZ2z2vjf5qKl6noXFuf54c2afLbxQHzO4V_QS9jKobKr MV2qd4fbaMeoEkMYFhCTc1p7wHPgXVFiKUYLtziXnelQb1itno0u6Ii0Z7xrAFEw.expXc5ZNi1j TdMksTyzUP9rfh9i_MzUUN8aLbhHZc2Je.qHbkffDuEapCJ0BiwT.JFr.PU7bNkxCoeFOoU0d9k3 M7L4OPaxK4FwcOygWJdMLcKyv5j1l7Od.Et9Q9R6B1iv9CclUE5pbh._nh4rVzy.Y_ANVNFVK6Wh 1L9DjEgUJ_rAOmcH2VAa44xD_Vci73YuFCJcHjOwGxgJweYQbG0wg.7IPfScGCz3IF6OYWBa0YIL LMRItIqaov8NPZEAIkSSZBqwvLdYEi4xSsT5VilBlsZ6yNjfZPC5nIaLcBntjvfRlB3fFFi2i8Cx HJ4geP6EqOrqjX3GMHxGZnK2q9TOu28fRU9TH8GGE.ReLgDSI_wHSEyHRxGHXnlqpzpy.9OZ1Uet 6UuSECRy2lYpxLL3Cepusfs0cz4SRvX_GcDAKiVdMFlGJX01UAVXyRnI5oN.P.INUfY6EKN34mFA fJeg6t6hhwLJp3N5zoiKAFm5Vv2_BBnTAwXIRfhIaqXztduINazwS_D9R4sT5QRmq1NVmQMjLh1L LzM4DoSqWXtpw4kbwO1XsCY9E15J5AhLhbdri3lnEZ2BOJ57ofyx6O4NUd2vwRpYfje91YX9U8xq 1MgcmW3WMb1kDSx10794rWiETZLyPf7xBTuoGqp35K8HVcnZ.SUqUfrk4sqZWnTQXyVtxYvCxbXW d7jfkloEzhFR3cOggEviexMQjQYnE2O.OgIPVPX2CmWwo0.ZSdlCNnO8OPXZ7uRuByHRmuQGAT9l cooqJzFXJ0BR9WX1PDHS.5u1fq1ICoOKLoNrqdKSudbsJOhdSvvaDCHm0FfhD_6AgraWuh4TuLK2 SS8wuamo5utNLN448QDdvff7CpYuPykX5dQXpL7EDDdMr0_OEjvsCUbR1F2TwF6xlLimOkxwOnNt _pQbABiWGWC1j245qO6II2T1BWsUKsltFFaA- Received: from sonic.gate.mail.ne1.yahoo.com by sonic308.consmr.mail.gq1.yahoo.com with HTTP; Thu, 25 Jun 2020 05:26:34 +0000 Received: by smtp413.mail.gq1.yahoo.com (VZM Hermes SMTP Server) with ESMTPA ID 834819637f2457c34ebb73ab79a37a10; Thu, 25 Jun 2020 05:26:31 +0000 (UTC) To: stable@vger.kernel.org, Greg Kroah-Hartman Subject: [PATCH 5.7.y] erofs: fix partially uninitialized misuse in z_erofs_onlinepage_fixup Date: Thu, 25 Jun 2020 13:26:18 +0800 Message-Id: <20200625052618.2316-1-hsiangkao@aol.com> X-Mailer: git-send-email 2.24.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit References: <20200625052618.2316-1-hsiangkao.ref@aol.com> X-BeenThere: linux-erofs@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development of Linux EROFS file system List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Gao Xiang via Linux-erofs Reply-To: Gao Xiang Cc: Hongyu Jin , linux-erofs@lists.ozlabs.org, LKML Errors-To: linux-erofs-bounces+linux-erofs=archiver.kernel.org@lists.ozlabs.org Sender: "Linux-erofs" From: Gao Xiang commit 3c597282887fd55181578996dca52ce697d985a5 upstream. Hongyu reported "id != index" in z_erofs_onlinepage_fixup() with specific aarch64 environment easily, which wasn't shown before. After digging into that, I found that high 32 bits of page->private was set to 0xaaaaaaaa rather than 0 (due to z_erofs_onlinepage_init behavior with specific compiler options). Actually we only use low 32 bits to keep the page information since page->private is only 4 bytes on most 32-bit platforms. However z_erofs_onlinepage_fixup() uses the upper 32 bits by mistake. Let's fix it now. Reported-and-tested-by: Hongyu Jin Fixes: 3883a79abd02 ("staging: erofs: introduce VLE decompression support") Cc: # 4.19+ Reviewed-by: Chao Yu Link: https://lore.kernel.org/r/20200618234349.22553-1-hsiangkao@aol.com Signed-off-by: Gao Xiang --- The same as 5.4.y. fs/erofs/zdata.h | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/fs/erofs/zdata.h b/fs/erofs/zdata.h index 7824f5563a55..9b66c28b3ae9 100644 --- a/fs/erofs/zdata.h +++ b/fs/erofs/zdata.h @@ -144,22 +144,22 @@ static inline void z_erofs_onlinepage_init(struct page *page) static inline void z_erofs_onlinepage_fixup(struct page *page, uintptr_t index, bool down) { - unsigned long *p, o, v, id; -repeat: - p = &page_private(page); - o = READ_ONCE(*p); + union z_erofs_onlinepage_converter u = { .v = &page_private(page) }; + int orig, orig_index, val; - id = o >> Z_EROFS_ONLINEPAGE_INDEX_SHIFT; - if (id) { +repeat: + orig = atomic_read(u.o); + orig_index = orig >> Z_EROFS_ONLINEPAGE_INDEX_SHIFT; + if (orig_index) { if (!index) return; - DBG_BUGON(id != index); + DBG_BUGON(orig_index != index); } - v = (index << Z_EROFS_ONLINEPAGE_INDEX_SHIFT) | - ((o & Z_EROFS_ONLINEPAGE_COUNT_MASK) + (unsigned int)down); - if (cmpxchg(p, o, v) != o) + val = (index << Z_EROFS_ONLINEPAGE_INDEX_SHIFT) | + ((orig & Z_EROFS_ONLINEPAGE_COUNT_MASK) + (unsigned int)down); + if (atomic_cmpxchg(u.o, orig, val) != orig) goto repeat; } -- 2.24.0