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=-12.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, 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=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 8FC17C433DF for ; Sat, 22 Aug 2020 20:50:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 694BC2072D for ; Sat, 22 Aug 2020 20:50:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=broadcom.com header.i=@broadcom.com header.b="Hhab7Toa" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728305AbgHVUuT (ORCPT ); Sat, 22 Aug 2020 16:50:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43624 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726535AbgHVUuS (ORCPT ); Sat, 22 Aug 2020 16:50:18 -0400 Received: from mail-wr1-x441.google.com (mail-wr1-x441.google.com [IPv6:2a00:1450:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2BECBC061573 for ; Sat, 22 Aug 2020 13:50:18 -0700 (PDT) Received: by mail-wr1-x441.google.com with SMTP id a15so5011753wrh.10 for ; Sat, 22 Aug 2020 13:50:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=broadcom.com; s=google; h=from:to:cc:subject:date:message-id; bh=awS83gVg339WvkVehjyxkJ0tva7kYJAQiAAlkyDZdCY=; b=Hhab7Toa7JqQg6Fs3xCaGrLLkK7u5Ls3HVTVp62/yPtGHAdmEI+CGJqcQx+Zsr5uRs LRusOTPsSwoHzk5sO6LFtSmubjbUWgXURg4s1njMDIWMXOSBWtYjhv09oxEi7rt0zIXY 7RAQ6GQsDp2PGMoc2o20aAl7QqTa+UhprHOak= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=awS83gVg339WvkVehjyxkJ0tva7kYJAQiAAlkyDZdCY=; b=qnr/da8W8w/+jAnkogR6OcDDnjhEvyMYbujiV5wcXV6TULkHlCiAajgFwI7T8At0Wo Codut64dWzj0hTo25c8o0jUrp76qgRye6uafTA9aSRQlVU90SGtGYGTUe9nh/MI8un58 DBN1XbQVBjgJ957vFNCcXfMP68h3tHwpJgnNkDPFRRBK59tAbTdSQ44v5u60mAYVNvEe JplUJc2CsNytwmaymIvCsHFbdj9vscqgDL7prj+4gEpuNTrExu+RMWEcyLr1ylxUdlmE o7mWG4mLaMKUIpDBqcpURIIKxOx263TaogBAdD0YtHiysGhzyzbXGnXR/LR7VMY4poxe /0Ow== X-Gm-Message-State: AOAM530POdA6Bb8VtTRjedIOM4o781k6pmndKtOOP5n++1QJgycOacSp wzWVHAzyOHltAXUwmTYMZKt/Fw== X-Google-Smtp-Source: ABdhPJxynv1Nm0KoX+Ru6/XDn803cx9lbNeDxDE59Kp8xjg81nYzHC9GGVXUlo/Af2VHftP5h/3wtg== X-Received: by 2002:a5d:544f:: with SMTP id w15mr8363433wrv.208.1598129416035; Sat, 22 Aug 2020 13:50:16 -0700 (PDT) Received: from lbrmn-mmayer.ric.broadcom.net ([192.19.228.250]) by smtp.gmail.com with ESMTPSA id n18sm13041935wrp.58.2020.08.22.13.50.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 22 Aug 2020 13:50:15 -0700 (PDT) Received: by lbrmn-mmayer.ric.broadcom.net (Postfix, from userid 1000) id E4FF6212A928; Sat, 22 Aug 2020 13:50:12 -0700 (PDT) From: Markus Mayer To: Florian Fainelli , Colin Ian King , Krzysztof Kozlowski Cc: Markus Mayer , BCM Kernel Feedback , Linux ARM Kernel , Linux Kernel Subject: [PATCH v3] memory: brcmstb_dpfe: fix array index out of bounds Date: Sat, 22 Aug 2020 13:50:00 -0700 Message-Id: <20200822205000.15841-1-mmayer@broadcom.com> X-Mailer: git-send-email 2.17.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We would overrun the error_text array if we hit a TIMEOUT condition, because we were using the error code "ETIMEDOUT" (which is 110) as an array index. We fix the problem by correcting the array index and by providing a function to retrieve error messages rather than accessing the array directly. The function includes a bounds check that prevents the array from being overrun. This patch was prepared in response to https://lkml.org/lkml/2020/8/18/505. Signed-off-by: Markus Mayer Acked-by: Florian Fainelli Fixes: 2f330caff577 ("memory: brcmstb: Add driver for DPFE") Reported-by: Colin Ian King --- Changes since v2: - Added "Fixes:" and "Reported-by:" - Fixed "From" address - No changes to the code Changes since v1: - Added link of the coverity report to the commit message. - Added Florian's ack. - Removed second "const" from get_error_text() return type (thanks to the kernel test robot). drivers/memory/brcmstb_dpfe.c | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) diff --git a/drivers/memory/brcmstb_dpfe.c b/drivers/memory/brcmstb_dpfe.c index e08528b12cbd..dcf50bb8dd69 100644 --- a/drivers/memory/brcmstb_dpfe.c +++ b/drivers/memory/brcmstb_dpfe.c @@ -188,11 +188,6 @@ struct brcmstb_dpfe_priv { struct mutex lock; }; -static const char * const error_text[] = { - "Success", "Header code incorrect", "Unknown command or argument", - "Incorrect checksum", "Malformed command", "Timed out", -}; - /* * Forward declaration of our sysfs attribute functions, so we can declare the * attribute data structures early. @@ -307,6 +302,20 @@ static const struct dpfe_api dpfe_api_v3 = { }, }; +static const char *get_error_text(unsigned int i) +{ + static const char * const error_text[] = { + "Success", "Header code incorrect", + "Unknown command or argument", "Incorrect checksum", + "Malformed command", "Timed out", "Unknown error", + }; + + if (unlikely(i >= ARRAY_SIZE(error_text))) + i = ARRAY_SIZE(error_text) - 1; + + return error_text[i]; +} + static bool is_dcpu_enabled(struct brcmstb_dpfe_priv *priv) { u32 val; @@ -445,7 +454,7 @@ static int __send_command(struct brcmstb_dpfe_priv *priv, unsigned int cmd, } if (resp != 0) { mutex_unlock(&priv->lock); - return -ETIMEDOUT; + return -ffs(DCPU_RET_ERR_TIMEDOUT); } /* Compute checksum over the message */ @@ -695,7 +704,7 @@ static ssize_t generic_show(unsigned int command, u32 response[], ret = __send_command(priv, command, response); if (ret < 0) - return sprintf(buf, "ERROR: %s\n", error_text[-ret]); + return sprintf(buf, "ERROR: %s\n", get_error_text(-ret)); return 0; } -- 2.17.1