From patchwork Mon Jul 12 06:09:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 475677 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, 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 C823CC07E9C for ; Mon, 12 Jul 2021 07:20:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B4F89613EC for ; Mon, 12 Jul 2021 07:20:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240959AbhGLHXU (ORCPT ); Mon, 12 Jul 2021 03:23:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:59320 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240184AbhGLHVQ (ORCPT ); Mon, 12 Jul 2021 03:21:16 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id AC920613EE; Mon, 12 Jul 2021 07:18:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626074308; bh=syAVqQuSoIiuS7JHQ+4SXvTlNSBhSa1x9TSIYG6imP0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=q20x5iuey4kBQJKt7PZEDsIvgsb6xPbQ0pqdl4gX0qmtKPrH0HC9sVcwh4Twq+Zn6 K2xk6aLRXPqneOCM3RI1w4toQIakK6xuroPOKPizQm6IDqR23XrVzFjCOB6E5JaeYE EwpO51I5Ae8n09kLhcl8P8ghOiZ2dt8i7FqME4pw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vladimir Oltean , "David S. Miller" , Sasha Levin Subject: [PATCH 5.12 493/700] net: dsa: sja1105: fix NULL pointer dereference in sja1105_reload_cbs() Date: Mon, 12 Jul 2021 08:09:36 +0200 Message-Id: <20210712061028.979830367@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210712060924.797321836@linuxfoundation.org> References: <20210712060924.797321836@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Vladimir Oltean [ Upstream commit be7f62eebaff2f86c1467a2d33930a0a7a87675b ] priv->cbs is an array of priv->info->num_cbs_shapers elements of type struct sja1105_cbs_entry which only get allocated if CONFIG_NET_SCH_CBS is enabled. However, sja1105_reload_cbs() is called from sja1105_static_config_reload() which in turn is called for any of the items in sja1105_reset_reasons, therefore during the normal runtime of the driver and not just from a code path which can be triggered by the tc-cbs offload. The sja1105_reload_cbs() function does not contain a check whether the priv->cbs array is NULL or not, it just assumes it isn't and proceeds to iterate through the credit-based shaper elements. This leads to a NULL pointer dereference. The solution is to return success if the priv->cbs array has not been allocated, since sja1105_reload_cbs() has nothing to do. Fixes: 4d7525085a9b ("net: dsa: sja1105: offload the Credit-Based Shaper qdisc") Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/dsa/sja1105/sja1105_main.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/dsa/sja1105/sja1105_main.c b/drivers/net/dsa/sja1105/sja1105_main.c index 926544440f02..42a0fb588f64 100644 --- a/drivers/net/dsa/sja1105/sja1105_main.c +++ b/drivers/net/dsa/sja1105/sja1105_main.c @@ -1798,6 +1798,12 @@ static int sja1105_reload_cbs(struct sja1105_private *priv) { int rc = 0, i; + /* The credit based shapers are only allocated if + * CONFIG_NET_SCH_CBS is enabled. + */ + if (!priv->cbs) + return 0; + for (i = 0; i < priv->info->num_cbs_shapers; i++) { struct sja1105_cbs_entry *cbs = &priv->cbs[i];