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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 357BFC19F2B for ; Wed, 27 Jul 2022 16:42:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239873AbiG0Qmp (ORCPT ); Wed, 27 Jul 2022 12:42:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57364 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239220AbiG0QmP (ORCPT ); Wed, 27 Jul 2022 12:42:15 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 148D75C357; Wed, 27 Jul 2022 09:29:56 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id DF5B261A39; Wed, 27 Jul 2022 16:29:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BE92EC433D6; Wed, 27 Jul 2022 16:29:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1658939395; bh=HBTuDHmlNIq/Hz/znquvPZXH2RPXYA59ZP/S06U5vHs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fCFlkXne+xvJ4NpRvMhL4G2jqN2oRS8kmNmYqJCBwCFpb0IYaHmsGPbHScLtwLMlP tnU4xovbf+XrwJ6lMdhdgtUPsy5SowECoow7VAQI4QTKEhsFdBO4loLzOkNmWFKgMp 1/5IW7jO6uqS84AICYHj2PSxlfZmZxxtrn2wvwWs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lukas Wunner , Marc Kleine-Budde , Mark Brown Subject: [PATCH 5.4 55/87] spi: bcm2835: bcm2835_spi_handle_err(): fix NULL pointer deref for non DMA transfers Date: Wed, 27 Jul 2022 18:10:48 +0200 Message-Id: <20220727161011.295157882@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220727161008.993711844@linuxfoundation.org> References: <20220727161008.993711844@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marc Kleine-Budde commit 4ceaa684459d414992acbefb4e4c31f2dfc50641 upstream. In case a IRQ based transfer times out the bcm2835_spi_handle_err() function is called. Since commit 1513ceee70f2 ("spi: bcm2835: Drop dma_pending flag") the TX and RX DMA transfers are unconditionally canceled, leading to NULL pointer derefs if ctlr->dma_tx or ctlr->dma_rx are not set. Fix the NULL pointer deref by checking that ctlr->dma_tx and ctlr->dma_rx are valid pointers before accessing them. Fixes: 1513ceee70f2 ("spi: bcm2835: Drop dma_pending flag") Cc: Lukas Wunner Signed-off-by: Marc Kleine-Budde Link: https://lore.kernel.org/r/20220719072234.2782764-1-mkl@pengutronix.de Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- drivers/spi/spi-bcm2835.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) --- a/drivers/spi/spi-bcm2835.c +++ b/drivers/spi/spi-bcm2835.c @@ -1159,10 +1159,14 @@ static void bcm2835_spi_handle_err(struc struct bcm2835_spi *bs = spi_controller_get_devdata(ctlr); /* if an error occurred and we have an active dma, then terminate */ - dmaengine_terminate_sync(ctlr->dma_tx); - bs->tx_dma_active = false; - dmaengine_terminate_sync(ctlr->dma_rx); - bs->rx_dma_active = false; + if (ctlr->dma_tx) { + dmaengine_terminate_sync(ctlr->dma_tx); + bs->tx_dma_active = false; + } + if (ctlr->dma_rx) { + dmaengine_terminate_sync(ctlr->dma_rx); + bs->rx_dma_active = false; + } bcm2835_spi_undo_prologue(bs); /* and reset */