This is a note to let you know that I've just added the patch titled
dmaengine: at_hdmac: fix potential NULL pointer dereference in atc_prep_dma_interleaved
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
dmaengine-at_hdmac-fix-potential-null-pointer-dereference-in-atc_prep_dma_interleaved.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Fri Feb 23 11:48:40 CET 2018
From: "Gustavo A. R. Silva" <garsilva@xxxxxxxxxxxxxx>
Date: Mon, 20 Nov 2017 08:28:14 -0600
Subject: dmaengine: at_hdmac: fix potential NULL pointer dereference in atc_prep_dma_interleaved
From: "Gustavo A. R. Silva" <garsilva@xxxxxxxxxxxxxx>
[ 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@xxxxxxxxxxxxxx>
Acked-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxxxxxx>
Signed-off-by: Vinod Koul <vinod.koul@xxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/dma/at_hdmac.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -709,7 +709,7 @@ atc_prep_dma_interleaved(struct dma_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;
@@ -721,6 +721,8 @@ atc_prep_dma_interleaved(struct dma_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,
Patches currently in stable-queue which might be from garsilva@xxxxxxxxxxxxxx are
queue-4.9/dmaengine-at_hdmac-fix-potential-null-pointer-dereference-in-atc_prep_dma_interleaved.patch