On Mon, May 9, 2011 at 6:05 PM, Vladimir Motyka <vladimir.motyka@xxxxxxxxx> wrote: > On 05/09/2011 04:32 PM, Julia Lawall wrote: >> On Mon, 9 May 2011, Vladimir Motyka wrote: >> >>> When allocation of idata fails there was a null dereferece. >> >> Why not have a different label for the two cases? ÂThat would make the >> code easier to statically analyze, and perhaps be more understandable as >> well. >> >> julia >> > I think You are right. So it could be better like this? > > diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c > index 3dec493..a03cdc6 100644 > --- a/drivers/mmc/card/block.c > +++ b/drivers/mmc/card/block.c > @@ -237,7 +237,7 @@ static struct mmc_blk_ioc_data > *mmc_blk_ioctl_copy_from_user( > Â Â Â Âidata = kzalloc(sizeof(*idata), GFP_KERNEL); > Â Â Â Âif (!idata) { > Â Â Â Â Â Â Â Âerr = -ENOMEM; > - Â Â Â Â Â Â Â goto copy_err; > + Â Â Â Â Â Â Â goto alloc_err; > Â Â Â Â} > > Â Â Â Âif (copy_from_user(&idata->ic, user, sizeof(idata->ic))) { > @@ -266,9 +266,9 @@ static struct mmc_blk_ioc_data > *mmc_blk_ioctl_copy_from_user( > Â Â Â Âreturn idata; > > Âcopy_err: > - Â Â Â if(idata) > - Â Â Â Â Â Â Â kfree(idata->buf); > + Â Â Â kfree(idata->buf); Make it one patch not series. > Â Â Â Âkfree(idata); > +alloc_err: > Â Â Â Âreturn ERR_PTR(err); > Â} > > Or it could return right after allocation fails so there needn't be > goto. It is simplier, but maybe worse looking and to read. What is your > opinion? > > Vladimir Motyka > >> >>> Signed-off-by: Vladimir Motyka <vladimir.motyka@xxxxxxxxx> >>> >>> --- >>> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c >>> index 407836d..3dec493 100644 >>> --- a/drivers/mmc/card/block.c >>> +++ b/drivers/mmc/card/block.c >>> @@ -266,10 +266,10 @@ static struct mmc_blk_ioc_data >>> *mmc_blk_ioctl_copy_from_user( >>> Â Â Âreturn idata; >>> >>> Âcopy_err: >>> - Â Âkfree(idata->buf); >>> + Â Âif(idata) >>> + Â Â Â Â Â Âkfree(idata->buf); >>> Â Â Âkfree(idata); >>> Â Â Âreturn ERR_PTR(err); >>> - >>> Â} >>> >>> Âstatic int mmc_blk_ioctl_cmd(struct block_device *bdev, >>> -- >>> To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in >>> the body of a message to majordomo@xxxxxxxxxxxxxxx >>> More majordomo info at Âhttp://vger.kernel.org/majordomo-info.html >>> > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at Âhttp://vger.kernel.org/majordomo-info.html > Please read the FAQ at Âhttp://www.tux.org/lkml/ > -- With Best Regards, Andy Shevchenko -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html