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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 BD290C64E69 for ; Tue, 27 Oct 2020 17:57:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F0A22076D for ; Tue, 27 Oct 2020 17:57:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603821423; bh=JZO0FMmtG4vn/Ir8BKBtAao/jx/uemYfhrNZ6ukyQ5c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=V5ZbrwLfyHYD0Pmo+G5/1QgoApAq1A0VIi9WMQ+i5sovUAD2Gquu/GQu0/4UyR1f4 wy7KrBDst5ieLDahv4KluzltPDPedUwlpO82Br0aCGTeCCs6xHtZgLD2LLl8v8aIZY Ipi94GorOWqEIyGgipyv/fACCqQRoV9nS3a+ls48= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1823038AbgJ0R45 (ORCPT ); Tue, 27 Oct 2020 13:56:57 -0400 Received: from mail.kernel.org ([198.145.29.99]:44396 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2509116AbgJ0OUd (ORCPT ); Tue, 27 Oct 2020 10:20:33 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 79150206FA; Tue, 27 Oct 2020 14:20:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603808433; bh=JZO0FMmtG4vn/Ir8BKBtAao/jx/uemYfhrNZ6ukyQ5c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=n7gxS0Q5HNCRgz4ov+QdR1oqxMCEn+E/83rOKvI365w+1tJr7YGbwIuyxoeSb+8MC +43y2X6eSxt4+09ADyKWYufHBT3DceJ5O06JW+KyEC2F3An6YAznNmChJyU3csLFRI PCDpdFEfMfZL4gDffHknk4p0lNC5xjOnBVxUp8WU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tom Rix , Thomas Winischhofer , Andrew Morton , Bartlomiej Zolnierkiewicz , Sasha Levin Subject: [PATCH 4.19 090/264] video: fbdev: sis: fix null ptr dereference Date: Tue, 27 Oct 2020 14:52:28 +0100 Message-Id: <20201027135434.926617654@linuxfoundation.org> X-Mailer: git-send-email 2.29.1 In-Reply-To: <20201027135430.632029009@linuxfoundation.org> References: <20201027135430.632029009@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Tom Rix [ Upstream commit ad6f93e9cd56f0b10e9b22e3e137d17a1a035242 ] Clang static analysis reports this representative error init.c:2501:18: warning: Array access (from variable 'queuedata') results in a null pointer dereference templ |= ((queuedata[i] & 0xc0) << 3); This is the problem block of code if(ModeNo > 0x13) { ... if(SiS_Pr->ChipType == SIS_730) { queuedata = &FQBQData730[0]; } else { queuedata = &FQBQData[0]; } } else { } queuedata is not set in the else block Reviewing the old code, the arrays FQBQData730 and FQBQData were used directly. So hoist the setting of queuedata out of the if-else block. Fixes: 544393fe584d ("[PATCH] sisfb update") Signed-off-by: Tom Rix Cc: Thomas Winischhofer Cc: Andrew Morton Signed-off-by: Bartlomiej Zolnierkiewicz Link: https://patchwork.freedesktop.org/patch/msgid/20200805145208.17727-1-trix@redhat.com Signed-off-by: Sasha Levin --- drivers/video/fbdev/sis/init.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/video/fbdev/sis/init.c b/drivers/video/fbdev/sis/init.c index dfe3eb769638b..fde27feae5d0c 100644 --- a/drivers/video/fbdev/sis/init.c +++ b/drivers/video/fbdev/sis/init.c @@ -2428,6 +2428,11 @@ SiS_SetCRT1FIFO_630(struct SiS_Private *SiS_Pr, unsigned short ModeNo, i = 0; + if (SiS_Pr->ChipType == SIS_730) + queuedata = &FQBQData730[0]; + else + queuedata = &FQBQData[0]; + if(ModeNo > 0x13) { /* Get VCLK */ @@ -2445,12 +2450,6 @@ SiS_SetCRT1FIFO_630(struct SiS_Private *SiS_Pr, unsigned short ModeNo, /* Get half colordepth */ colorth = colortharray[(SiS_Pr->SiS_ModeType - ModeEGA)]; - if(SiS_Pr->ChipType == SIS_730) { - queuedata = &FQBQData730[0]; - } else { - queuedata = &FQBQData[0]; - } - do { templ = SiS_CalcDelay2(SiS_Pr, queuedata[i]) * VCLK * colorth; -- 2.25.1