From 9983a5bba09e5b56b73881ce99b95b0723f72bc3 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 75f38d19fcbe..ba8994e10ed9 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -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; -- GitLab