dmaengine: at_hdmac: fix memory leak in at_dma_xlate()

The leak was found when opening/closing a serial port a great number of
time, increasing kmalloc-32 in slabinfo.

Each time the port was opened, dma_request_slave_channel() was called.
Then, in at_dma_xlate(), atslave was allocated with devm_kzalloc() and
never freed. (Well, it was free at module unload, but that's not what we
want).
So, here, kzalloc is more suited for the job since it has to be freed in
atc_free_chan_resources().

Cc: [email protected]
Fixes: bbe89c8e3d ("at_hdmac: move to generic DMA binding")
Reported-by: Mario Forner <[email protected]>
Suggested-by: Alexandre Belloni <[email protected]>
Acked-by: Alexandre Belloni <[email protected]>
Acked-by: Ludovic Desroches <[email protected]>
Signed-off-by: Richard Genoud <[email protected]>
Signed-off-by: Vinod Koul <[email protected]>
This commit is contained in:
Richard Genoud 2018-11-27 17:06:34 +01:00 • committed by Vinod Koul
commit 98f5f93225

View file

@ -1641,6 +1641,12 @@ static void atc_free_chan_resources(struct dma_chan *chan)
atchan->descs_allocated = 0;
atchan->status = 0;
/*
* Free atslave allocated in at_dma_xlate()
*/
kfree(chan->private);
chan->private = NULL;
dev_vdbg(chan2dev(chan), "free_chan_resources: done\n");
}
@ -1675,7 +1681,7 @@ static struct dma_chan *at_dma_xlate(struct of_phandle_args *dma_spec,
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
atslave = devm_kzalloc(&dmac_pdev->dev, sizeof(*atslave), GFP_KERNEL);
atslave = kzalloc(sizeof(*atslave), GFP_KERNEL);
if (!atslave)
return NULL;