From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765511AbdEWXmi (ORCPT ); Tue, 23 May 2017 19:42:38 -0400 Received: from gateway32.websitewelcome.com ([192.185.145.100]:38722 "EHLO gateway32.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759869AbdEWXmd (ORCPT ); Tue, 23 May 2017 19:42:33 -0400 Date: Tue, 23 May 2017 18:42:27 -0500 From: "Gustavo A. R. Silva" To: Ulf Hansson , Florian Fainelli , Ray Jui , Scott Branden , bcm-kernel-feedback-list@broadcom.com, Eric Anholt , Stefan Wahren Cc: linux-mmc@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] mmc: host: fix potential null pointer dereference Message-ID: <20170523234227.GA13018@embeddedgus> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.23 (2014-03-12) X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 189.152.160.17 X-Exim-ID: 1dDJRd-000GGt-LT X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedgus) [189.152.160.17]:44694 X-Source-Auth: garsilva@embeddedor.com X-Email-Count: 16 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Null check at line 1165: if (mrq->cmd), implies that mrq->cmd might be NULL. Add null checks before dereferencing pointer mrq->cmd in order to avoid any potential NULL pointer dereference. Addresses-Coverity-ID: 1408740 Signed-off-by: Gustavo A. R. Silva --- drivers/mmc/host/bcm2835.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/host/bcm2835.c b/drivers/mmc/host/bcm2835.c index 1f343a4..abba9a2 100644 --- a/drivers/mmc/host/bcm2835.c +++ b/drivers/mmc/host/bcm2835.c @@ -1172,7 +1172,10 @@ static void bcm2835_request(struct mmc_host *mmc, struct mmc_request *mrq) if (mrq->data && !is_power_of_2(mrq->data->blksz)) { dev_err(dev, "unsupported block size (%d bytes)\n", mrq->data->blksz); - mrq->cmd->error = -EINVAL; + + if (mrq->cmd) + mrq->cmd->error = -EINVAL; + mmc_request_done(mmc, mrq); return; } @@ -1194,7 +1197,10 @@ static void bcm2835_request(struct mmc_host *mmc, struct mmc_request *mrq) readl(host->ioaddr + SDCMD) & SDCMD_CMD_MASK, edm); bcm2835_dumpregs(host); - mrq->cmd->error = -EILSEQ; + + if (mrq->cmd) + mrq->cmd->error = -EILSEQ; + bcm2835_finish_request(host); mutex_unlock(&host->mutex); return; @@ -1207,7 +1213,7 @@ static void bcm2835_request(struct mmc_host *mmc, struct mmc_request *mrq) if (!host->use_busy) bcm2835_finish_command(host); } - } else if (bcm2835_send_command(host, mrq->cmd)) { + } else if (mrq->cmd && bcm2835_send_command(host, mrq->cmd)) { if (host->data && host->dma_desc) { /* DMA transfer starts now, PIO starts after irq */ bcm2835_start_dma(host); -- 2.5.0