dmaengine: at_hdmac: fix potential NULL pointer dereference in atc_prep_dma_interleaved
[ Upstream commit 62a277d43d47e74972de44d33bd3763e31992414 ]
_xt_ is being dereferenced before it is null checked, hence there is a
potential null pointer dereference.
Fix this by moving the pointer dereference after _xt_ has been null
checked.
This issue was detected with the help of Coccinelle.
Fixes: 4483320e241c ("dmaengine: Use Pointer xt after NULL check.")
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index a4c8f80..e2cec5b 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -709,7 +709,7 @@
unsigned long flags)
{
struct at_dma_chan *atchan = to_at_dma_chan(chan);
- struct data_chunk *first = xt->sgl;
+ struct data_chunk *first;
struct at_desc *desc = NULL;
size_t xfer_count;
unsigned int dwidth;
@@ -721,6 +721,8 @@
if (unlikely(!xt || xt->numf != 1 || !xt->frame_size))
return NULL;
+ first = xt->sgl;
+
dev_info(chan2dev(chan),
"%s: src=%pad, dest=%pad, numf=%d, frame_size=%d, flags=0x%lx\n",
__func__, &xt->src_start, &xt->dst_start, xt->numf,