6.6-stable review patch. If anyone has any objections, please let me know.
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From: Amelie Delaunay amelie.delaunay@foss.st.com
[ Upstream commit 9bb4af400c386374ab1047df44c508512c08c31f ]
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 amelie.delaunay@foss.st.com Signed-off-by: Olivier Moysan olivier.moysan@foss.st.com Link: https://patch.msgid.link/20241105140242.527279-1-olivier.moysan@foss.st.com Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 a359b528b26b7..4e17909d21267 100644 --- a/sound/soc/stm/stm32_spdifrx.c +++ b/sound/soc/stm/stm32_spdifrx.c @@ -943,7 +943,7 @@ 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)