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From:   Peter Ujfalusi <peter.ujfalusi@ti.com>
To:     <vkoul@kernel.org>
CC:     <dan.j.williams@intel.com>, <dmaengine@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <alexandru.ardelean@analog.com>,
        <s.hauer@pengutronix.de>
Subject: [PATCH] dmaengine: virt-dma: Fix access after free in vcna_complete()
Date:   Fri, 20 Dec 2019 15:11:00 +0200
Message-ID: <20191220131100.21804-1-peter.ujfalusi@ti.com>
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Sender: linux-kernel-owner@vger.kernel.org
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vchan_vdesc_fini() is freeing up 'vd' so the access to vd->tx_result is
via already freed up memory.

Move the vchan_vdesc_fini() after invoking the callback to avoid this.

Fixes: 09d5b702b0f97 ("dmaengine: virt-dma: store result on dma descriptor")
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
---
 drivers/dma/virt-dma.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/dma/virt-dma.c b/drivers/dma/virt-dma.c
index ec4adf4260a0..256fc662c500 100644
--- a/drivers/dma/virt-dma.c
+++ b/drivers/dma/virt-dma.c
@@ -104,9 +104,8 @@ static void vchan_complete(unsigned long arg)
 		dmaengine_desc_get_callback(&vd->tx, &cb);
 
 		list_del(&vd->node);
-		vchan_vdesc_fini(vd);
-
 		dmaengine_desc_callback_invoke(&cb, &vd->tx_result);
+		vchan_vdesc_fini(vd);
 	}
 }
 
-- 
Peter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
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