Commit 62a277d4 authored Nov 20, 2017 by Gustavo A. R. Silva Committed by Vinod Koul Nov 29, 2017

dmaengine: at_hdmac: fix potential NULL pointer dereference in atc_prep_dma_interleaved



_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: 4483320e ("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>

parent 5c9afbda

drivers/dma/at_hdmac.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -708,7 +708,7 @@ atc_prep_dma_interleaved(struct dma_chan *chan,
		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;
		@@ -720,6 +720,8 @@ atc_prep_dma_interleaved(struct dma_chan *chan,
		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,

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