| Message ID | 20170523002507.GA16670@embeddedgus (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, May 23, 2017 at 2:25 AM, Gustavo A. R. Silva <garsilva@embeddedor.com> wrote: > Add null check before dereferencing pointer desc > > Addresses-Coverity-ID: 1397997 > Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> > --- > drivers/spi/spi-s3c64xx.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c > index b392cca..9f1013e 100644 > --- a/drivers/spi/spi-s3c64xx.c > +++ b/drivers/spi/spi-s3c64xx.c > @@ -306,6 +306,12 @@ static void prepare_dma(struct s3c64xx_spi_dma_data *dma, > desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents, > dma->direction, DMA_PREP_INTERRUPT); > > + if (!desc) { > + dev_err(&sdd->master->dev, > + "%s:dmaengine_prep_slave_sg Failed\n", __func__); > + return; > + } Although the check itself looks needed, but I think you did not handle the error at all. You just bail out before submitting dma descriptor but except that, everything else goes like there was no error. It might work, might not... did you test this error path? How does it behave? Best regards, Krzysztof
On Tue, May 23, 2017 at 9:24 AM, Krzysztof Kozlowski <krzk@kernel.org> wrote: > On Tue, May 23, 2017 at 2:25 AM, Gustavo A. R. Silva > <garsilva@embeddedor.com> wrote: >> Add null check before dereferencing pointer desc >> >> Addresses-Coverity-ID: 1397997 >> Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> >> --- >> drivers/spi/spi-s3c64xx.c | 6 ++++++ >> 1 file changed, 6 insertions(+) >> >> diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c >> index b392cca..9f1013e 100644 >> --- a/drivers/spi/spi-s3c64xx.c >> +++ b/drivers/spi/spi-s3c64xx.c >> @@ -306,6 +306,12 @@ static void prepare_dma(struct s3c64xx_spi_dma_data *dma, >> desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents, >> dma->direction, DMA_PREP_INTERRUPT); >> >> + if (!desc) { >> + dev_err(&sdd->master->dev, >> + "%s:dmaengine_prep_slave_sg Failed\n", __func__); >> + return; >> + } > > Although the check itself looks needed, but I think you did not handle > the error at all. You just bail out before submitting dma descriptor > but except that, everything else goes like there was no error. It > might work, might not... did you test this error path? How does it > behave? I.e. does it fall back to PIO? Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
Hi Gustavo, > desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents, > dma->direction, DMA_PREP_INTERRUPT); > > + if (!desc) { > + dev_err(&sdd->master->dev, > + "%s:dmaengine_prep_slave_sg Failed\n", __func__); > + return; > + } > + I'm sorry, I would nack this patch for now. There was a smilar I sent before, but, as Krzysztof said, this needs more testing and a proper solution. That's anyway in my todo list. Thanks, Andi
Hi Andi, Quoting Andi Shyti <andi.shyti@samsung.com>: > Hi Gustavo, > >> desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents, >> dma->direction, DMA_PREP_INTERRUPT); >> >> + if (!desc) { >> + dev_err(&sdd->master->dev, >> + "%s:dmaengine_prep_slave_sg Failed\n", __func__); >> + return; >> + } >> + > > I'm sorry, I would nack this patch for now. There was a smilar I > sent before, but, as Krzysztof said, this needs more testing and > a proper solution. > Yeah, I get it. > That's anyway in my todo list. > That's great. > Thanks, > Andi Thanks! -- Gustavo A. R. Silva
diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c index b392cca..9f1013e 100644 --- a/drivers/spi/spi-s3c64xx.c +++ b/drivers/spi/spi-s3c64xx.c @@ -306,6 +306,12 @@ static void prepare_dma(struct s3c64xx_spi_dma_data *dma, desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents, dma->direction, DMA_PREP_INTERRUPT); + if (!desc) { + dev_err(&sdd->master->dev, + "%s:dmaengine_prep_slave_sg Failed\n", __func__); + return; + } + desc->callback = s3c64xx_spi_dmacb; desc->callback_param = dma;
Add null check before dereferencing pointer desc Addresses-Coverity-ID: 1397997 Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> --- drivers/spi/spi-s3c64xx.c | 6 ++++++ 1 file changed, 6 insertions(+)