Re: [PATCH v1] drivers:testing:Handle possible memory leaks

[Rafael J. Wysocki]

On Thu, Aug 22, 2024 at 5:39 AM Yang Ruibin <11162571@xxxxxxxx> wrote:
>
> When copy_from_user() fails, -EFAULT is returned without
> releasing the memory previously allocated by kmalloc().
>
> Signed-off-by: Yang Ruibin <11162571@xxxxxxxx>
> ---
>  drivers/thermal/testing/command.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/thermal/testing/command.c b/drivers/thermal/testing/command.c
> index 7868caee3..b95bcb94e 100644
> --- a/drivers/thermal/testing/command.c
> +++ b/drivers/thermal/testing/command.c
> @@ -150,9 +150,10 @@ static ssize_t tt_command_process(struct dentry *dentry, const char __user *user
>         if (!buf)
>                 return -ENOMEM;
>
> -       if (copy_from_user(buf, user_buf, count))
> +       if (copy_from_user(buf, user_buf, count)) {
> +               kfree(buf);
>                 return -EFAULT;
> +       }
>
>         buf[count] = '\0';
>         strim(buf);
> --

Have you missed the __free() annotation on "buf"?