Re: [PATCH v2] platform/x86/amd/pmf: Fix memory leak in amd_pmf_get_pb_data()

From: Hans de Goede
Date: Fri Jan 26 2024 - 14:16:57 EST


Hi,

On 1/24/24 02:29, Cong Liu wrote:
> amd_pmf_get_pb_data() will allocate memory for the policy buffer,
> but does not free it if copy_from_user() fails. This leads to a memory
> leak.
>
> Fixes: 10817f28e533 ("platform/x86/amd/pmf: Add capability to sideload of policy binary")
> Reviewed-by: Shyam Sundar S K <Shyam-sundar.S-k@xxxxxxx>
> Signed-off-by: Cong Liu <liucong2@xxxxxxxxxx>

Thank you for your patch/series, I've applied this patch
(series) to my review-hans branch:
https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git/log/?h=review-hans

Note it will show up in the pdx86 review-hans branch once I've
pushed my local branch there, which might take a while.

I will include this patch in my next fixes pull-req to Linus
for the current kernel development cycle.

Regards,

Hans



> ---
> drivers/platform/x86/amd/pmf/tee-if.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/platform/x86/amd/pmf/tee-if.c b/drivers/platform/x86/amd/pmf/tee-if.c
> index 502ce93d5cdd..f8c0177afb0d 100644
> --- a/drivers/platform/x86/amd/pmf/tee-if.c
> +++ b/drivers/platform/x86/amd/pmf/tee-if.c
> @@ -298,8 +298,10 @@ static ssize_t amd_pmf_get_pb_data(struct file *filp, const char __user *buf,
> if (!new_policy_buf)
> return -ENOMEM;
>
> - if (copy_from_user(new_policy_buf, buf, length))
> + if (copy_from_user(new_policy_buf, buf, length)) {
> + kfree(new_policy_buf);
> return -EFAULT;
> + }
>
> kfree(dev->policy_buf);
> dev->policy_buf = new_policy_buf;