| Message ID | 4DC8117C.7060200@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
I guess there is also a point at which idata has been successfully allocated but idata->buf has not. julia On Mon, 9 May 2011, Vladimir Motyka wrote: > When allocation of idata fails there was a null dereference. > > Signed-off-by: Vladimir Motyka <vladimir.motyka@gmail.com> > --- > diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c > index 407836d..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( > idata = kzalloc(sizeof(*idata), GFP_KERNEL); > if (!idata) { > err = -ENOMEM; > - goto copy_err; > + goto alloc_err; > } > > if (copy_from_user(&idata->ic, user, sizeof(idata->ic))) { > @@ -268,8 +268,8 @@ static struct mmc_blk_ioc_data > *mmc_blk_ioctl_copy_from_user( > copy_err: > kfree(idata->buf); > kfree(idata); > +alloc_err: > return ERR_PTR(err); > - > } > > static 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@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 05/09/2011 06:12 PM, Julia Lawall wrote: > I guess there is also a point at which idata has been successfully > allocated but idata->buf has not. > > julia > Yes there is. Thank You for pointing out. Vladimir Motyka > On Mon, 9 May 2011, Vladimir Motyka wrote: > >> When allocation of idata fails there was a null dereference. >> >> Signed-off-by: Vladimir Motyka <vladimir.motyka@gmail.com> >> --- >> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c >> index 407836d..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( >> idata = kzalloc(sizeof(*idata), GFP_KERNEL); >> if (!idata) { >> err = -ENOMEM; >> - goto copy_err; >> + goto alloc_err; >> } >> >> if (copy_from_user(&idata->ic, user, sizeof(idata->ic))) { >> @@ -268,8 +268,8 @@ static struct mmc_blk_ioc_data >> *mmc_blk_ioctl_copy_from_user( >> copy_err: >> kfree(idata->buf); >> kfree(idata); >> +alloc_err: >> return ERR_PTR(err); >> - >> } >> >> static 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@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, May 9, 2011 at 7:12 PM, Julia Lawall <julia@diku.dk> wrote: > I guess there is also a point at which idata has been successfully > allocated but idata->buf has not. And? kfree() simple ignores NULL pointers. I would prefer to see previous version of patch, but let maintainer to choose.
On Tue, 10 May 2011, Andy Shevchenko wrote: > On Mon, May 9, 2011 at 7:12 PM, Julia Lawall <julia@diku.dk> wrote: > > I guess there is also a point at which idata has been successfully > > allocated but idata->buf has not. > And? kfree() simple ignores NULL pointers. Unnecessarily calling a function suggests that calling that function is necessary when it is not. But it is probably not a big deal, especially for a well known function like kfree. julia > I would prefer to see previous version of patch, but let maintainer to choose. > > -- > With Best Regards, > Andy Shevchenko > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index 407836d..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( idata = kzalloc(sizeof(*idata), GFP_KERNEL); if (!idata) { err = -ENOMEM; - goto copy_err; + goto alloc_err; }
When allocation of idata fails there was a null dereference. Signed-off-by: Vladimir Motyka <vladimir.motyka@gmail.com> --- if (copy_from_user(&idata->ic, user, sizeof(idata->ic))) { @@ -268,8 +268,8 @@ static struct mmc_blk_ioc_data *mmc_blk_ioctl_copy_from_user( copy_err: kfree(idata->buf); kfree(idata); +alloc_err: return ERR_PTR(err); - } static int mmc_blk_ioctl_cmd(struct block_device *bdev, -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html