[PATCH 5.4 123/191] dmaengine: virt-dma: Fix access after free in vchan_complete()
From: Greg Kroah-Hartman
Date: Tue Jan 07 2020 - 16:23:33 EST
From: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
commit 24461d9792c2c706092805ff1b067628933441bd upstream.
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>
Reviewed-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20191220131100.21804-1-peter.ujfalusi@xxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/dma/virt-dma.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
--- a/drivers/dma/virt-dma.c
+++ b/drivers/dma/virt-dma.c
@@ -104,9 +104,8 @@ static void vchan_complete(unsigned long
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);
}
}