From patchwork Fri Oct 30 10:22:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Chen X-Patchwork-Id: 1390930 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=huawei.com Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4CMz0l12kZz9s0b for ; Fri, 30 Oct 2020 21:23:19 +1100 (AEDT) Received: from localhost ([::1]:60488 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kYRYz-000454-5u for incoming@patchwork.ozlabs.org; Fri, 30 Oct 2020 06:23:17 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:47066) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kYRYh-00044g-9N; Fri, 30 Oct 2020 06:22:59 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:2426) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kYRYe-00082C-U1; Fri, 30 Oct 2020 06:22:58 -0400 Received: from DGGEMS408-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4CMz096vdNzLrL1; Fri, 30 Oct 2020 18:22:49 +0800 (CST) Received: from [10.174.187.138] (10.174.187.138) by DGGEMS408-HUB.china.huawei.com (10.3.19.208) with Microsoft SMTP Server id 14.3.487.0; Fri, 30 Oct 2020 18:22:45 +0800 Message-ID: <5F9BE974.3040806@huawei.com> Date: Fri, 30 Oct 2020 18:22:44 +0800 From: AlexChen User-Agent: Mozilla/5.0 (Windows NT 6.2; WOW64; rv:17.0) Gecko/20130509 Thunderbird/17.0.6 MIME-Version: 1.0 To: , Subject: [PATCH] hw/display/exynos4210_fimd: Fix potential NULL pointer dereference X-Originating-IP: [10.174.187.138] X-CFilter-Loop: Reflected Received-SPF: pass client-ip=45.249.212.191; envelope-from=alex.chen@huawei.com; helo=szxga05-in.huawei.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/10/30 06:22:50 X-ACL-Warn: Detected OS = Linux 3.1-3.10 [fuzzy] X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-trivial@nongnu.org, qemu-arm@nongnu.org, QEMU Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" In exynos4210_fimd_update(), the pointer s is dereferenced before being check if it is valid, which may lead to NULL pointer dereference. So move the assignment to global_width after checking that the s is valid Reported-by: Euler Robot Signed-off-by: Alex Chen --- hw/display/exynos4210_fimd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/display/exynos4210_fimd.c b/hw/display/exynos4210_fimd.c index 4c16e1f5a0..a1179d2f89 100644 --- a/hw/display/exynos4210_fimd.c +++ b/hw/display/exynos4210_fimd.c @@ -1275,12 +1275,12 @@ static void exynos4210_fimd_update(void *opaque) bool blend = false; uint8_t *host_fb_addr; bool is_dirty = false; - const int global_width = (s->vidtcon[2] & FIMD_VIDTCON2_SIZE_MASK) + 1; if (!s || !s->console || !s->enabled || surface_bits_per_pixel(qemu_console_surface(s->console)) == 0) { return; } + const int global_width = (s->vidtcon[2] & FIMD_VIDTCON2_SIZE_MASK) + 1; exynos4210_update_resolution(s); surface = qemu_console_surface(s->console);