lkml.org 
[lkml]   [2019]   [Feb]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Date
Subject[PATCH 3.16 247/305] dmaengine: at_hdmac: fix memory leak in at_dma_xlate()
3.16.63-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Richard Genoud <richard.genoud@gmail.com>

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().

Fixes: bbe89c8e3d59 ("at_hdmac: move to generic DMA binding")
Reported-by: Mario Forner <m.forner@be4energy.com>
Suggested-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/dma/at_hdmac.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -1231,6 +1231,12 @@ static void atc_free_chan_resources(stru
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");
}

@@ -1265,7 +1271,7 @@ static struct dma_chan *at_dma_xlate(str
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;

\
 
 \ /
  Last update: 2019-02-03 15:23    [W:1.429 / U:3.316 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site