[PATCH] dmaengine: virt-dma: Fix access after free in vcna_complete()

From: Peter Ujfalusi
Date: Fri Dec 20 2019 - 08:10:55 EST


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@xxxxxx>
---
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

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