linux-kernel - [PATCH 3.18 09/54] dmaengine: at_hdmac: fix memory leak in at_dma

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20181211151546.497323659@linuxfoundation.org>
Date:   Tue, 11 Dec 2018 16:40:57 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Mario Forner <m.forner@...energy.com>,
        Alexandre Belloni <alexandre.belloni@...tlin.com>,
        Ludovic Desroches <ludovic.desroches@...rochip.com>,
        Richard Genoud <richard.genoud@...il.com>,
        Vinod Koul <vkoul@...nel.org>
Subject: [PATCH 3.18 09/54] dmaengine: at_hdmac: fix memory leak in at_dma_xlate()

3.18-stable review patch.  If anyone has any objections, please let me know.

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

From: Richard Genoud <richard.genoud@...il.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().

Cc: stable@...r.kernel.org
Fixes: bbe89c8e3d59 ("at_hdmac: move to generic DMA binding")
Reported-by: Mario Forner <m.forner@...energy.com>
Suggested-by: Alexandre Belloni <alexandre.belloni@...tlin.com>
Acked-by: Alexandre Belloni <alexandre.belloni@...tlin.com>
Acked-by: Ludovic Desroches <ludovic.desroches@...rochip.com>
Signed-off-by: Richard Genoud <richard.genoud@...il.com>
Signed-off-by: Vinod Koul <vkoul@...nel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 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
@@ -1232,6 +1232,12 @@ 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");
 }
 
@@ -1266,7 +1272,7 @@ 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;