| Message ID | 20240110222717.193719-1-prabhakar.mahadev-lad.rj@bp.renesas.com (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | c4d6dcb3b6250ea546a952ad33382daf7cd32425 |
| Delegated to: | Geert Uytterhoeven |
| Headers | show |
| Series | dmaengine: sh: rz-dmac: Avoid format-overflow warning | expand |
Hi Prabhakar, On Wed, Jan 10, 2024 at 11:27 PM Prabhakar <prabhakar.csengg@gmail.com> wrote: > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> > > The max channel count for RZ DMAC is 16, hence use u8 instead of unsigned > int and make the pdev_irqname string long enough to avoid the warning. Note that the danger lies into someone changing RZ_DMAC_MAX_CHANNELS later... > This fixes the below issue: > drivers/dma/sh/rz-dmac.c: In function ‘rz_dmac_probe’: > drivers/dma/sh/rz-dmac.c:770:34: warning: ‘%u’ directive writing between 1 and 10 bytes into a region of size 3 [-Wformat-overflow=] > 770 | sprintf(pdev_irqname, "ch%u", index); > | ^~ > In function ‘rz_dmac_chan_probe’, > inlined from ‘rz_dmac_probe’ at drivers/dma/sh/rz-dmac.c:910:9: > drivers/dma/sh/rz-dmac.c:770:31: note: directive argument in the range [0, 4294967294] > 770 | sprintf(pdev_irqname, "ch%u", index); > | ^~~~~~ > drivers/dma/sh/rz-dmac.c:770:9: note: ‘sprintf’ output between 4 and 13 bytes into a destination of size 5 > 770 | sprintf(pdev_irqname, "ch%u", index); > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > While at it use scnprintf() instead of sprintf() to make the code > more robust. > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Some nits below... > --- a/drivers/dma/sh/rz-dmac.c > +++ b/drivers/dma/sh/rz-dmac.c > @@ -845,9 +845,9 @@ static int rz_dmac_probe(struct platform_device *pdev) > struct dma_device *engine; > struct rz_dmac *dmac; > int channel_num; > - unsigned int i; > int ret; > int irq; > + u8 i; Personally, I'm not much a fan of making loop counters smaller than (unsigned) int. If you do go this way, you should change channel_num to u8, too, just like i in rz_dmac_remove(). > > dmac = devm_kzalloc(&pdev->dev, sizeof(*dmac), GFP_KERNEL); > if (!dmac) Gr{oetje,eeting}s, Geert
On Wed, 10 Jan 2024 22:27:17 +0000, Prabhakar wrote: > The max channel count for RZ DMAC is 16, hence use u8 instead of unsigned > int and make the pdev_irqname string long enough to avoid the warning. > > This fixes the below issue: > drivers/dma/sh/rz-dmac.c: In function ‘rz_dmac_probe’: > drivers/dma/sh/rz-dmac.c:770:34: warning: ‘%u’ directive writing between 1 and 10 bytes into a region of size 3 [-Wformat-overflow=] > 770 | sprintf(pdev_irqname, "ch%u", index); > | ^~ > In function ‘rz_dmac_chan_probe’, > inlined from ‘rz_dmac_probe’ at drivers/dma/sh/rz-dmac.c:910:9: > drivers/dma/sh/rz-dmac.c:770:31: note: directive argument in the range [0, 4294967294] > 770 | sprintf(pdev_irqname, "ch%u", index); > | ^~~~~~ > drivers/dma/sh/rz-dmac.c:770:9: note: ‘sprintf’ output between 4 and 13 bytes into a destination of size 5 > 770 | sprintf(pdev_irqname, "ch%u", index); > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > [...] Applied, thanks! [1/1] dmaengine: sh: rz-dmac: Avoid format-overflow warning commit: c4d6dcb3b6250ea546a952ad33382daf7cd32425 Best regards,
diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index fea5bda34bc2..1f1e86ba5c66 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -755,11 +755,11 @@ static struct dma_chan *rz_dmac_of_xlate(struct of_phandle_args *dma_spec, static int rz_dmac_chan_probe(struct rz_dmac *dmac, struct rz_dmac_chan *channel, - unsigned int index) + u8 index) { struct platform_device *pdev = to_platform_device(dmac->dev); struct rz_lmdesc *lmdesc; - char pdev_irqname[5]; + char pdev_irqname[6]; char *irqname; int ret; @@ -767,7 +767,7 @@ static int rz_dmac_chan_probe(struct rz_dmac *dmac, channel->mid_rid = -EINVAL; /* Request the channel interrupt. */ - sprintf(pdev_irqname, "ch%u", index); + scnprintf(pdev_irqname, sizeof(pdev_irqname), "ch%u", index); channel->irq = platform_get_irq_byname(pdev, pdev_irqname); if (channel->irq < 0) return channel->irq; @@ -845,9 +845,9 @@ static int rz_dmac_probe(struct platform_device *pdev) struct dma_device *engine; struct rz_dmac *dmac; int channel_num; - unsigned int i; int ret; int irq; + u8 i; dmac = devm_kzalloc(&pdev->dev, sizeof(*dmac), GFP_KERNEL); if (!dmac)