From patchwork Fri Dec 8 23:59:49 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Colin King X-Patchwork-Id: 10103429 X-Patchwork-Delegate: rjw@sisk.pl Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 45A1860210 for ; Fri, 8 Dec 2017 23:59:54 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3729B28FDD for ; Fri, 8 Dec 2017 23:59:54 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2911728FE1; Fri, 8 Dec 2017 23:59:54 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A5CE228FDD for ; Fri, 8 Dec 2017 23:59:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753799AbdLHX7w (ORCPT ); Fri, 8 Dec 2017 18:59:52 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:50835 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753790AbdLHX7w (ORCPT ); Fri, 8 Dec 2017 18:59:52 -0500 Received: from 1.general.cking.uk.vpn ([10.172.193.212] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1eNSYX-0007FQ-OM; Fri, 08 Dec 2017 23:59:49 +0000 From: Colin King To: "Rafael J . Wysocki" , Len Brown , linux-acpi@vger.kernel.org Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] ACPI / CPPC: remove initial assignment of pcc_ss_data Date: Fri, 8 Dec 2017 23:59:49 +0000 Message-Id: <20171208235949.15713-1-colin.king@canonical.com> X-Mailer: git-send-email 2.14.1 MIME-Version: 1.0 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Colin Ian King The initialization of pcc_ss_data from pcc_data[pcc_ss_id] before pcc_ss_id is being range checked could lead to an out-of-bounds array read. This very same initialization is also being performed after the range check on pcc_ss_id, so we can just remove this problematic and also redundant assignment to fix the issue. Detected by cppcheck: warning: Value stored to 'pcc_ss_data' during its initialization is never read Fixes: commit 85b1407bf6d2 ("ACPI / CPPC: Make CPPC ACPI driver aware of PCC subspace IDs") Signed-off-by: Colin Ian King --- drivers/acpi/cppc_acpi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index 30e84cc600ae..06ea4749ebd9 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -1171,7 +1171,7 @@ int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls) struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpu); struct cpc_register_resource *desired_reg; int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu); - struct cppc_pcc_data *pcc_ss_data = pcc_data[pcc_ss_id]; + struct cppc_pcc_data *pcc_ss_data; int ret = 0; if (!cpc_desc || pcc_ss_id < 0) {