From f7d0d9589cfeb825a795b0c0d562a11b0ad58c4c Mon Sep 17 00:00:00 2001 From: Richard Genoud Date: Tue, 27 Nov 2018 17:06:34 +0100 Subject: [PATCH] dmaengine: at_hdmac: fix memory leak in at_dma_xlate() commit 98f5f932254b88ce828bc8e4d1642d14e5854caa upstream. 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: stable@vger.kernel.org Fixes: bbe89c8e3d59 ("at_hdmac: move to generic DMA binding") Reported-by: Mario Forner Suggested-by: Alexandre Belloni Acked-by: Alexandre Belloni Acked-by: Ludovic Desroches Signed-off-by: Richard Genoud Signed-off-by: Vinod Koul Signed-off-by: Greg Kroah-Hartman --- drivers/dma/at_hdmac.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index ca9dd26..dfc5edf0 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -1232,6 +1232,12 @@ static void atc_free_chan_resources(struct dma_chan *chan) atchan->status = 0; atchan->remain_desc = 0; + /* + * Free atslave allocated in at_dma_xlate() + */ + kfree(chan->private); + chan->private = NULL; + dev_vdbg(chan2dev(chan), "free_chan_resources: done\n"); } @@ -1266,7 +1272,7 @@ 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; -- 2.7.4