[PATCH] 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: 4483320e241c ("dmaengine: Use Pointer xt after NULL check.") Signed-off-by: Gustavo A. R. Silva --- drivers/dma/at_hdmac.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index fbab271..a861b5b 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -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 intdwidth; @@ -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, -- 2.7.4
Re: [PATCH] dmaengine: at_hdmac: fix potential NULL pointer dereference in atc_prep_dma_interleaved
On Mon, Nov 20, 2017 at 08:28:14AM -0600, Gustavo A. R. Silva wrote: > _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 Acked-by: Ludovic Desroches Thanks > --- > drivers/dma/at_hdmac.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c > index fbab271..a861b5b 100644 > --- a/drivers/dma/at_hdmac.c > +++ b/drivers/dma/at_hdmac.c > @@ -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 intdwidth; > @@ -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, > -- > 2.7.4 > > > ___ > linux-arm-kernel mailing list > linux-arm-ker...@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Re: [PATCH] dmaengine: at_hdmac: fix potential NULL pointer dereference in atc_prep_dma_interleaved
On Mon, Nov 20, 2017 at 08:28:14AM -0600, Gustavo A. R. Silva wrote: > _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. Applied, thanks -- ~Vinod