On Wed, Sep 23, 2020 at 08:19:18AM +0000, Tudor.Ambarus@microchip.com wrote:

On 9/23/20 11:13 AM, Tudor.Ambarus@microchip.com wrote:

quoted

Hi, Pavel,

On 9/20/20 11:28 AM, Pavel Machek wrote:

quoted

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This fixes memory leak in at_hdmac. Mainline does not have the same
problem.

Signed-off-by: Pavel Machek (CIP) <redacted>

diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index 86427f6ba78c..0847b2055857 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c

@@ -1714,8 +1714,10 @@ static struct dma_chan *at_dma_xlate(struct of_phandle_args *dma_spec,
        atslave->dma_dev = &dmac_pdev->dev;

        chan = dma_request_channel(mask, at_dma_filter, atslave);
-       if (!chan)
+       if (!chan) {
+               kfree(atslave);
                return NULL;
+       }

Thanks for submitting this to stable. While the fix is good, you can instead
cherry-pick the commit that hit upstream. In order to do that cleanly on top
of v4.19.145, you have to pick two other fixes:

commit a6e7f19c9100 ("dmaengine: at_hdmac: Substitute kzalloc with kmalloc")
commit 3832b78b3ec2 ("dmaengine: at_hdmac: add missing put_device() call in at_dma_xlate()")
commit a6e7f19c9100 ("dmaengine: at_hdmac: Substitute kzalloc with kmalloc")

this last commit should have been
commit e097eb7473d9 ("dmaengine: at_hdmac: add missing kfree() call in at_dma_xlate()")

bad copy and paste :)

So are all 3 of those needed on both 5.4.y and 4.19.y to resolve this
issue?

thanks,

greg k-h