2020-11-20 07:48:53

by Qinglang Miao

Subject: [PATCH] memstick: fix a double-free bug in memstick_check

kfree(host->card) has been called in put_device so that
another kfree would raise cause a double-free bug.

Fixes: 0193383a5833 ("memstick: core: fix device_register() error handling")
Reported-by: Hulk Robot <[email protected]>
Signed-off-by: Qinglang Miao <[email protected]>
---
drivers/memstick/core/memstick.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/drivers/memstick/core/memstick.c b/drivers/memstick/core/memstick.c
index ef03d6faf..12bc3f5a6 100644
--- a/drivers/memstick/core/memstick.c
+++ b/drivers/memstick/core/memstick.c
@@ -468,7 +468,6 @@ static void memstick_check(struct work_struct *work)
host->card = card;
if (device_register(&card->dev)) {
put_device(&card->dev);
- kfree(host->card);
host->card = NULL;
}
} else
--
2.23.0

2020-11-23 16:13:36

by Ulf Hansson

Subject: Re: [PATCH] memstick: fix a double-free bug in memstick_check

On Fri, 20 Nov 2020 at 08:44, Qinglang Miao <[email protected]> wrote:
>
> kfree(host->card) has been called in put_device so that
> another kfree would raise cause a double-free bug.
>
> Fixes: 0193383a5833 ("memstick: core: fix device_register() error handling")
> Reported-by: Hulk Robot <[email protected]>
> Signed-off-by: Qinglang Miao <[email protected]>

Applied for next, thanks!

Kind regards
Uffe


> ---
> drivers/memstick/core/memstick.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/drivers/memstick/core/memstick.c b/drivers/memstick/core/memstick.c
> index ef03d6faf..12bc3f5a6 100644
> --- a/drivers/memstick/core/memstick.c
> +++ b/drivers/memstick/core/memstick.c
> @@ -468,7 +468,6 @@ static void memstick_check(struct work_struct *work)
> host->card = card;
> if (device_register(&card->dev)) {
> put_device(&card->dev);
> - kfree(host->card);
> host->card = NULL;
> }
> } else
> --
> 2.23.0
>