| Message ID | 20230926032244.11560-1-dinghao.liu@zju.edu.cn (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2] ieee802154: ca8210: Fix a potential UAF in ca8210_probe | expand |
Hi Dinghao, dinghao.liu@zju.edu.cn 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 <dinghao.liu@zju.edu.cn> > --- > > 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
Hello. On 26.09.23 10:02, Miquel Raynal wrote: > Hi Dinghao, > > dinghao.liu@zju.edu.cn 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 <dinghao.liu@zju.edu.cn> >> --- >> >> 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
> Missing Cc stable, this needs to be backported. I will cc stable (stable@vger.kernel.org) 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
Hi, On Tue, Sep 26, 2023 at 4:29 AM Stefan Schmidt <stefan@datenfreihafen.org> wrote: > > Hello. > > On 26.09.23 10:02, Miquel Raynal wrote: > > Hi Dinghao, > > > > dinghao.liu@zju.edu.cn 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 <dinghao.liu@zju.edu.cn> > >> --- > >> > >> 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
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);
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 <dinghao.liu@zju.edu.cn> --- 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(-)