From 9bb4af400c386374ab1047df44c508512c08c31f Mon Sep 17 00:00:00 2001 From: Amelie Delaunay Date: Tue, 5 Nov 2024 15:02:42 +0100 Subject: [PATCH] ASoC: stm32: spdifrx: fix dma channel release in stm32_spdifrx_remove In case of error when requesting ctrl_chan DMA channel, ctrl_chan is not null. So the release of the dma channel leads to the following issue: [ 4.879000] st,stm32-spdifrx 500d0000.audio-controller: dma_request_slave_channel error -19 [ 4.888975] Unable to handle kernel NULL pointer dereference at virtual address 000000000000003d [...] [ 5.096577] Call trace: [ 5.099099] dma_release_channel+0x24/0x100 [ 5.103235] stm32_spdifrx_remove+0x24/0x60 [snd_soc_stm32_spdifrx] [ 5.109494] stm32_spdifrx_probe+0x320/0x4c4 [snd_soc_stm32_spdifrx] To avoid this issue, release channel only if the pointer is valid. Fixes: 794df9448edb ("ASoC: stm32: spdifrx: manage rebind issue") Signed-off-by: Amelie Delaunay Signed-off-by: Olivier Moysan Link: https://patch.msgid.link/20241105140242.527279-1-olivier.moysan@foss.st.com Signed-off-by: Mark Brown --- sound/soc/stm/stm32_spdifrx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sound/soc/stm/stm32_spdifrx.c b/sound/soc/stm/stm32_spdifrx.c index d1b32ba1e1a2..9e30852de93c 100644 --- a/sound/soc/stm/stm32_spdifrx.c +++ b/sound/soc/stm/stm32_spdifrx.c @@ -939,7 +939,7 @@ static void stm32_spdifrx_remove(struct platform_device *pdev) { struct stm32_spdifrx_data *spdifrx = platform_get_drvdata(pdev); - if (spdifrx->ctrl_chan) + if (!IS_ERR(spdifrx->ctrl_chan)) dma_release_channel(spdifrx->ctrl_chan); if (spdifrx->dmab)