From: Ross Zwisler Date: Mon, 29 Apr 2019 18:25:17 +0000 (-0600) Subject: ASoC: Intel: avoid Oops if DMA setup fails X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=e212945fe5258efb2bd316500e5132df7521069e;p=sagit-ice-cold%2Fkernel_xiaomi_msm8998.git ASoC: Intel: avoid Oops if DMA setup fails commit 0efa3334d65b7f421ba12382dfa58f6ff5bf83c4 upstream. Currently in sst_dsp_new() if we get an error return from sst_dma_new() we just print an error message and then still complete the function successfully. This means that we are trying to run without sst->dma properly set up, which will result in NULL pointer dereference when sst->dma is later used. This was happening for me in sst_dsp_dma_get_channel(): struct sst_dma *dma = dsp->dma; ... dma->ch = dma_request_channel(mask, dma_chan_filter, dsp); This resulted in: BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 IP: sst_dsp_dma_get_channel+0x4f/0x125 [snd_soc_sst_firmware] Fix this by adding proper error handling for the case where we fail to set up DMA. This change only affects Haswell and Broadwell systems. Baytrail systems explicilty opt-out of DMA via sst->pdata->resindex_dma_base being set to -1. Signed-off-by: Ross Zwisler Cc: stable@vger.kernel.org Acked-by: Pierre-Louis Bossart Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- diff --git a/sound/soc/intel/common/sst-dsp.c b/sound/soc/intel/common/sst-dsp.c index c9452e02e0dd..c0a50ecb6dbd 100644 --- a/sound/soc/intel/common/sst-dsp.c +++ b/sound/soc/intel/common/sst-dsp.c @@ -463,11 +463,15 @@ struct sst_dsp *sst_dsp_new(struct device *dev, goto irq_err; err = sst_dma_new(sst); - if (err) - dev_warn(dev, "sst_dma_new failed %d\n", err); + if (err) { + dev_err(dev, "sst_dma_new failed %d\n", err); + goto dma_err; + } return sst; +dma_err: + free_irq(sst->irq, sst); irq_err: if (sst->ops->free) sst->ops->free(sst);