From patchwork Wed Apr 27 11:53:21 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stanislav Meduna X-Patchwork-Id: 8956031 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 9C3099F1D3 for ; Wed, 27 Apr 2016 11:55:23 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 361CB201E4 for ; Wed, 27 Apr 2016 11:55:18 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 39E5D201C7 for ; Wed, 27 Apr 2016 11:55:17 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1avO2h-00008q-Qu; Wed, 27 Apr 2016 11:54:07 +0000 Received: from www.meduna.org ([92.240.244.38] helo=meduna.org) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1avO2U-0008Tv-Dv for linux-arm-kernel@lists.infradead.org; Wed, 27 Apr 2016 11:53:55 +0000 Received: from 78-141-77-45.dynamic.orange.sk ([78.141.77.45] helo=[192.168.130.22]) by meduna.org with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.72) (envelope-from ) id 1avO22-00008q-Gf; Wed, 27 Apr 2016 13:53:28 +0200 To: linux-kernel@vger.kernel.org, "linux-arm-kernel@lists.infradead.org" From: Stanislav Meduna Subject: [PATCH] nvmem/mxs-ocotp: fix buffer overflow in read Message-ID: <201ccd58-8735-02d8-b4e4-9d2eda828fd8@meduna.org> Date: Wed, 27 Apr 2016 13:53:21 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.0 MIME-Version: 1.0 X-Authenticated-User: stano@meduna.org X-Authenticator: dovecot_plain X-Spam-Score: -6.9 X-Spam-Score-Int: -68 X-Exim-Version: 4.72 (build at 13-Jul-2014 12:42:58) X-Date: 2016-04-27 13:53:28 X-Connected-IP: 78.141.77.45:61033 X-Message-Linecount: 47 X-Body-Linecount: 35 X-Message-Size: 1530 X-Body-Size: 1031 X-Received-Count: 1 X-Recipient-Count: 2 X-Local-Recipient-Count: 2 X-Local-Recipient-Defer-Count: 0 X-Local-Recipient-Fail-Count: 0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160427_045354_664755_05836536 X-CRM114-Status: UNSURE ( 9.94 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -2.9 (--) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-5.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch fixes the issue where the mxs_ocotp_read is reading the ocotp in reg_size steps but decrements the remaining size by 1. The number of iterations is thus four times higher, overwriting the area behind the output buffer. Fixes: c01e9a11ab6f ("nvmem: add driver for ocotp in i.MX23 and i.MX28") Tested-by: Stefan Wahren --- drivers/nvmem/mxs-ocotp.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/nvmem/mxs-ocotp.c b/drivers/nvmem/mxs-ocotp.c index 8ba19bb..2bb3c57 100644 --- a/drivers/nvmem/mxs-ocotp.c +++ b/drivers/nvmem/mxs-ocotp.c @@ -94,7 +94,7 @@ static int mxs_ocotp_read(void *context, const void *reg, size_t reg_size, if (ret) goto close_banks; - while (val_size) { + while (val_size >= reg_size) { if ((offset < OCOTP_DATA_OFFSET) || (offset % 16)) { /* fill up non-data register */ *buf = 0; @@ -103,7 +103,7 @@ static int mxs_ocotp_read(void *context, const void *reg, size_t reg_size, } buf++; - val_size--; + val_size -= reg_size; offset += reg_size; }