From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 454AD7C for ; Mon, 24 Apr 2023 13:28:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id ADD9BC433D2; Mon, 24 Apr 2023 13:28:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1682342888; bh=MyUoH/X7oQvxECshEf1qBDO57rFW1uTCmTA5sPUwDDo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Qn0lx+LSAoNeCLCGgKo9jUYnUTsgoGO54prVtJa0YY0Qj3pnyV+DvUqPu1zyJQMa8 ChcspQWrhhR/VSQRy3a1zUKJevff9rpLN4DU3h1FSfj0UZnZntbLJs0C2VpyEIF6HP /RTCeALrJQPuxm6A4ZDLve6HCkb4A0WmklfoPKRE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Nikita Zhandarovich , Shengjiu Wang , Mark Brown , Natalia Petrova Subject: [PATCH 6.1 96/98] ASoC: fsl_asrc_dma: fix potential null-ptr-deref Date: Mon, 24 Apr 2023 15:17:59 +0200 Message-Id: <20230424131137.622262214@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230424131133.829259077@linuxfoundation.org> References: <20230424131133.829259077@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Nikita Zhandarovich commit 86a24e99c97234f87d9f70b528a691150e145197 upstream. dma_request_slave_channel() may return NULL which will lead to NULL pointer dereference error in 'tmp_chan->private'. Correct this behaviour by, first, switching from deprecated function dma_request_slave_channel() to dma_request_chan(). Secondly, enable sanity check for the resuling value of dma_request_chan(). Also, fix description that follows the enacted changes and that concerns the use of dma_request_slave_channel(). Fixes: 706e2c881158 ("ASoC: fsl_asrc_dma: Reuse the dma channel if available in Back-End") Co-developed-by: Natalia Petrova Signed-off-by: Nikita Zhandarovich Acked-by: Shengjiu Wang Link: https://lore.kernel.org/r/20230417133242.53339-1-n.zhandarovich@fintech.ru Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- sound/soc/fsl/fsl_asrc_dma.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) --- a/sound/soc/fsl/fsl_asrc_dma.c +++ b/sound/soc/fsl/fsl_asrc_dma.c @@ -209,14 +209,19 @@ static int fsl_asrc_dma_hw_params(struct be_chan = soc_component_to_pcm(component_be)->chan[substream->stream]; tmp_chan = be_chan; } - if (!tmp_chan) - tmp_chan = dma_request_slave_channel(dev_be, tx ? "tx" : "rx"); + if (!tmp_chan) { + tmp_chan = dma_request_chan(dev_be, tx ? "tx" : "rx"); + if (IS_ERR(tmp_chan)) { + dev_err(dev, "failed to request DMA channel for Back-End\n"); + return -EINVAL; + } + } /* * An EDMA DEV_TO_DEV channel is fixed and bound with DMA event of each * peripheral, unlike SDMA channel that is allocated dynamically. So no * need to configure dma_request and dma_request2, but get dma_chan of - * Back-End device directly via dma_request_slave_channel. + * Back-End device directly via dma_request_chan. */ if (!asrc->use_edma) { /* Get DMA request of Back-End */