If of_clk_add_provider() fails in ca8210_register_ext_clock(),
it calls clk_unregister() to release priv->clk and returns an
error. However, the caller ca8210_probe() then calls ca8210_remove(),
where priv->clk is freed again in ca8210_unregister_ext_clock(). In
this case, a use-after-free may happen in the second time we call
clk_unregister().
Fix this by removing the first clk_unregister(). Also, priv->clk could
be an error code on failure of clk_register_fixed_rate(). Use
IS_ERR_OR_NULL to catch this case in ca8210_unregister_ext_clock().
Fixes: ded845a781a5 ("ieee802154: Add CA8210 IEEE 802.15.4 device driver")
Signed-off-by: Dinghao Liu <[email protected]>
---
Changelog:
v2: -Remove the first clk_unregister() instead of nulling priv->clk.
---
drivers/net/ieee802154/ca8210.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c
index aebb19f1b3a4..b35c6f59bd1a 100644
--- a/drivers/net/ieee802154/ca8210.c
+++ b/drivers/net/ieee802154/ca8210.c
@@ -2759,7 +2759,6 @@ static int ca8210_register_ext_clock(struct spi_device *spi)
}
ret = of_clk_add_provider(np, of_clk_src_simple_get, priv->clk);
if (ret) {
- clk_unregister(priv->clk);
dev_crit(
&spi->dev,
"Failed to register external clock as clock provider\n"
@@ -2780,7 +2779,7 @@ static void ca8210_unregister_ext_clock(struct spi_device *spi)
{
struct ca8210_priv *priv = spi_get_drvdata(spi);
- if (!priv->clk)
+ if (IS_ERR_OR_NULL(priv->clk))
return
of_clk_del_provider(spi->dev.of_node);
--
2.17.1
> Missing Cc stable, this needs to be backported.
I will cc stable ([email protected]) for the next version, thanks!
> > diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c
> > index aebb19f1b3a4..b35c6f59bd1a 100644
> > --- a/drivers/net/ieee802154/ca8210.c
> > +++ b/drivers/net/ieee802154/ca8210.c
> > @@ -2759,7 +2759,6 @@ static int ca8210_register_ext_clock(struct spi_device *spi)
> > }
> > ret = of_clk_add_provider(np, of_clk_src_simple_get, priv->clk);
> > if (ret) {
> > - clk_unregister(priv->clk);
> > dev_crit(
> > &spi->dev,
> > "Failed to register external clock as clock provider\n"
>
> I was hoping you would simplify this function a bit more.
I understand. In the next patch version, I will just return of_clk_add_provider().
>
> > @@ -2780,7 +2779,7 @@ static void ca8210_unregister_ext_clock(struct spi_device *spi)
> > {
> > struct ca8210_priv *priv = spi_get_drvdata(spi);
> >
> > - if (!priv->clk)
> > + if (IS_ERR_OR_NULL(priv->clk))
> > return
> >
> > of_clk_del_provider(spi->dev.of_node);
>
> Alex, Stefan, who handles wpan and wpan/next this release?
>
Is there any problem I need to handle in the next patch?
Regards,
Dinghao
Hello.
On 26.09.23 10:02, Miquel Raynal wrote:
> Hi Dinghao,
>
> [email protected] wrote on Tue, 26 Sep 2023 11:22:44 +0800:
>
>> If of_clk_add_provider() fails in ca8210_register_ext_clock(),
>> it calls clk_unregister() to release priv->clk and returns an
>> error. However, the caller ca8210_probe() then calls ca8210_remove(),
>> where priv->clk is freed again in ca8210_unregister_ext_clock(). In
>> this case, a use-after-free may happen in the second time we call
>> clk_unregister().
>>
>> Fix this by removing the first clk_unregister(). Also, priv->clk could
>> be an error code on failure of clk_register_fixed_rate(). Use
>> IS_ERR_OR_NULL to catch this case in ca8210_unregister_ext_clock().
>>
>> Fixes: ded845a781a5 ("ieee802154: Add CA8210 IEEE 802.15.4 device driver")
>
> Missing Cc stable, this needs to be backported.
>
>> Signed-off-by: Dinghao Liu <[email protected]>
>> ---
>>
>> Changelog:
>>
>> v2: -Remove the first clk_unregister() instead of nulling priv->clk.
>> ---
>> drivers/net/ieee802154/ca8210.c | 3 +--
>> 1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c
>> index aebb19f1b3a4..b35c6f59bd1a 100644
>> --- a/drivers/net/ieee802154/ca8210.c
>> +++ b/drivers/net/ieee802154/ca8210.c
>> @@ -2759,7 +2759,6 @@ static int ca8210_register_ext_clock(struct spi_device *spi)
>> }
>> ret = of_clk_add_provider(np, of_clk_src_simple_get, priv->clk);
>> if (ret) {
>> - clk_unregister(priv->clk);
>> dev_crit(
>> &spi->dev,
>> "Failed to register external clock as clock provider\n"
>
> I was hoping you would simplify this function a bit more.
>
>> @@ -2780,7 +2779,7 @@ static void ca8210_unregister_ext_clock(struct spi_device *spi)
>> {
>> struct ca8210_priv *priv = spi_get_drvdata(spi);
>>
>> - if (!priv->clk)
>> + if (IS_ERR_OR_NULL(priv->clk))
>> return
>>
>> of_clk_del_provider(spi->dev.of_node);
>
> Alex, Stefan, who handles wpan and wpan/next this release?
IIRC it would be me for wpan and Alex for wpan-next.
regards
Stefan Schmidt
Hi Dinghao,
[email protected] wrote on Tue, 26 Sep 2023 11:22:44 +0800:
> If of_clk_add_provider() fails in ca8210_register_ext_clock(),
> it calls clk_unregister() to release priv->clk and returns an
> error. However, the caller ca8210_probe() then calls ca8210_remove(),
> where priv->clk is freed again in ca8210_unregister_ext_clock(). In
> this case, a use-after-free may happen in the second time we call
> clk_unregister().
>
> Fix this by removing the first clk_unregister(). Also, priv->clk could
> be an error code on failure of clk_register_fixed_rate(). Use
> IS_ERR_OR_NULL to catch this case in ca8210_unregister_ext_clock().
>
> Fixes: ded845a781a5 ("ieee802154: Add CA8210 IEEE 802.15.4 device driver")
Missing Cc stable, this needs to be backported.
> Signed-off-by: Dinghao Liu <[email protected]>
> ---
>
> Changelog:
>
> v2: -Remove the first clk_unregister() instead of nulling priv->clk.
> ---
> drivers/net/ieee802154/ca8210.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c
> index aebb19f1b3a4..b35c6f59bd1a 100644
> --- a/drivers/net/ieee802154/ca8210.c
> +++ b/drivers/net/ieee802154/ca8210.c
> @@ -2759,7 +2759,6 @@ static int ca8210_register_ext_clock(struct spi_device *spi)
> }
> ret = of_clk_add_provider(np, of_clk_src_simple_get, priv->clk);
> if (ret) {
> - clk_unregister(priv->clk);
> dev_crit(
> &spi->dev,
> "Failed to register external clock as clock provider\n"
I was hoping you would simplify this function a bit more.
> @@ -2780,7 +2779,7 @@ static void ca8210_unregister_ext_clock(struct spi_device *spi)
> {
> struct ca8210_priv *priv = spi_get_drvdata(spi);
>
> - if (!priv->clk)
> + if (IS_ERR_OR_NULL(priv->clk))
> return
>
> of_clk_del_provider(spi->dev.of_node);
Alex, Stefan, who handles wpan and wpan/next this release?
Thanks,
Miquèl
Hi,
On Tue, Sep 26, 2023 at 4:29 AM Stefan Schmidt
<[email protected]> wrote:
>
> Hello.
>
> On 26.09.23 10:02, Miquel Raynal wrote:
> > Hi Dinghao,
> >
> > [email protected] wrote on Tue, 26 Sep 2023 11:22:44 +0800:
> >
> >> If of_clk_add_provider() fails in ca8210_register_ext_clock(),
> >> it calls clk_unregister() to release priv->clk and returns an
> >> error. However, the caller ca8210_probe() then calls ca8210_remove(),
> >> where priv->clk is freed again in ca8210_unregister_ext_clock(). In
> >> this case, a use-after-free may happen in the second time we call
> >> clk_unregister().
> >>
> >> Fix this by removing the first clk_unregister(). Also, priv->clk could
> >> be an error code on failure of clk_register_fixed_rate(). Use
> >> IS_ERR_OR_NULL to catch this case in ca8210_unregister_ext_clock().
> >>
> >> Fixes: ded845a781a5 ("ieee802154: Add CA8210 IEEE 802.15.4 device driver")
> >
> > Missing Cc stable, this needs to be backported.
> >
> >> Signed-off-by: Dinghao Liu <[email protected]>
> >> ---
> >>
> >> Changelog:
> >>
> >> v2: -Remove the first clk_unregister() instead of nulling priv->clk.
> >> ---
> >> drivers/net/ieee802154/ca8210.c | 3 +--
> >> 1 file changed, 1 insertion(+), 2 deletions(-)
> >>
> >> diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c
> >> index aebb19f1b3a4..b35c6f59bd1a 100644
> >> --- a/drivers/net/ieee802154/ca8210.c
> >> +++ b/drivers/net/ieee802154/ca8210.c
> >> @@ -2759,7 +2759,6 @@ static int ca8210_register_ext_clock(struct spi_device *spi)
> >> }
> >> ret = of_clk_add_provider(np, of_clk_src_simple_get, priv->clk);
> >> if (ret) {
> >> - clk_unregister(priv->clk);
> >> dev_crit(
> >> &spi->dev,
> >> "Failed to register external clock as clock provider\n"
> >
> > I was hoping you would simplify this function a bit more.
> >
> >> @@ -2780,7 +2779,7 @@ static void ca8210_unregister_ext_clock(struct spi_device *spi)
> >> {
> >> struct ca8210_priv *priv = spi_get_drvdata(spi);
> >>
> >> - if (!priv->clk)
> >> + if (IS_ERR_OR_NULL(priv->clk))
> >> return
> >>
> >> of_clk_del_provider(spi->dev.of_node);
> >
> > Alex, Stefan, who handles wpan and wpan/next this release?
>
> IIRC it would be me for wpan and Alex for wpan-next.
That's okay for me.
- Alex