diff mbox series

[4.4,v1] power: supply: ltc2941-battery-gauge: fix use-after-free

Message ID 20190919190208.13648-1-TheSven73@gmail.com (mailing list archive)
State Not Applicable, archived
Headers show
Series [4.4,v1] power: supply: ltc2941-battery-gauge: fix use-after-free | expand

Commit Message

Sven Van Asbroeck Sept. 19, 2019, 7:02 p.m. UTC
This driver's remove path calls cancel_delayed_work().
However, that function does not wait until the work function
finishes. This could mean that the work function is still
running after the driver's remove function has finished,
which would result in a use-after-free.

Fix by calling cancel_delayed_work_sync(), which ensures that
that the work is properly cancelled, no longer running, and
unable to re-schedule itself.

This issue was detected with the help of Coccinelle.

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Sven Van Asbroeck <TheSven73@gmail.com>
---
 drivers/power/ltc2941-battery-gauge.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Greg KH Dec. 2, 2019, 6:43 p.m. UTC | #1
On Thu, Sep 19, 2019 at 03:02:08PM -0400, Sven Van Asbroeck wrote:
> This driver's remove path calls cancel_delayed_work().
> However, that function does not wait until the work function
> finishes. This could mean that the work function is still
> running after the driver's remove function has finished,
> which would result in a use-after-free.
> 
> Fix by calling cancel_delayed_work_sync(), which ensures that
> that the work is properly cancelled, no longer running, and
> unable to re-schedule itself.
> 
> This issue was detected with the help of Coccinelle.
> 
> Cc: stable <stable@vger.kernel.org>
> Signed-off-by: Sven Van Asbroeck <TheSven73@gmail.com>
> ---
>  drivers/power/ltc2941-battery-gauge.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/power/ltc2941-battery-gauge.c b/drivers/power/ltc2941-battery-gauge.c
> index da49436176cd..30a9014b2f95 100644
> --- a/drivers/power/ltc2941-battery-gauge.c
> +++ b/drivers/power/ltc2941-battery-gauge.c
> @@ -449,7 +449,7 @@ static int ltc294x_i2c_remove(struct i2c_client *client)
>  {
>  	struct ltc294x_info *info = i2c_get_clientdata(client);
>  
> -	cancel_delayed_work(&info->work);
> +	cancel_delayed_work_sync(&info->work);
>  	power_supply_unregister(info->supply);
>  	return 0;
>  }
> -- 
> 2.17.1
> 

What is the git commit id of this patch in Linus's tree?

thanks,

greg k-h
Sven Van Asbroeck Dec. 2, 2019, 7:59 p.m. UTC | #2
On Mon, Dec 2, 2019 at 1:43 PM Greg KH <greg@kroah.com> wrote:
>
> What is the git commit id of this patch in Linus's tree?

As far as I know, the mainline version of this patch is still queued up
in Sebastian's 'fixes' branch, and has not made it out to Linus's
tree yet.

https://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply.git/log/?h=fixes
Greg KH Feb. 7, 2020, 8:51 a.m. UTC | #3
On Mon, Dec 02, 2019 at 02:59:26PM -0500, Sven Van Asbroeck wrote:
> On Mon, Dec 2, 2019 at 1:43 PM Greg KH <greg@kroah.com> wrote:
> >
> > What is the git commit id of this patch in Linus's tree?
> 
> As far as I know, the mainline version of this patch is still queued up
> in Sebastian's 'fixes' branch, and has not made it out to Linus's
> tree yet.
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply.git/log/?h=fixes

Now queued up, thanks!

greg k-h
diff mbox series

Patch

diff --git a/drivers/power/ltc2941-battery-gauge.c b/drivers/power/ltc2941-battery-gauge.c
index da49436176cd..30a9014b2f95 100644
--- a/drivers/power/ltc2941-battery-gauge.c
+++ b/drivers/power/ltc2941-battery-gauge.c
@@ -449,7 +449,7 @@  static int ltc294x_i2c_remove(struct i2c_client *client)
 {
 	struct ltc294x_info *info = i2c_get_clientdata(client);
 
-	cancel_delayed_work(&info->work);
+	cancel_delayed_work_sync(&info->work);
 	power_supply_unregister(info->supply);
 	return 0;
 }