2022-11-29 02:16:38

by Yu Liao

Subject: [PATCH] platform/x86: mxm-wmi: fix memleak in mxm_wmi_call_mx[ds|mx]()

The ACPI buffer memory (out.pointer) returned by wmi_evaluate_method()
is not freed after the call, so it leads to memory leak.

The method results in ACPI buffer is not used, so just pass NULL to
wmi_evaluate_method() which fixes the memory leak.

Fixes: 99b38b4acc0d ("platform/x86: add MXM WMI driver.")
Signed-off-by: Yu Liao <[email protected]>
---
drivers/platform/x86/mxm-wmi.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/platform/x86/mxm-wmi.c b/drivers/platform/x86/mxm-wmi.c
index 9a19fbd2f734..9a457956025a 100644
--- a/drivers/platform/x86/mxm-wmi.c
+++ b/drivers/platform/x86/mxm-wmi.c
@@ -35,13 +35,11 @@ int mxm_wmi_call_mxds(int adapter)
.xarg = 1,
};
struct acpi_buffer input = { (acpi_size)sizeof(args), &args };
- struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
acpi_status status;

printk("calling mux switch %d\n", adapter);

- status = wmi_evaluate_method(MXM_WMMX_GUID, 0x0, adapter, &input,
- &output);
+ status = wmi_evaluate_method(MXM_WMMX_GUID, 0x0, adapter, &input, NULL);

if (ACPI_FAILURE(status))
return status;
@@ -60,13 +58,11 @@ int mxm_wmi_call_mxmx(int adapter)
.xarg = 1,
};
struct acpi_buffer input = { (acpi_size)sizeof(args), &args };
- struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
acpi_status status;

printk("calling mux switch %d\n", adapter);

- status = wmi_evaluate_method(MXM_WMMX_GUID, 0x0, adapter, &input,
- &output);
+ status = wmi_evaluate_method(MXM_WMMX_GUID, 0x0, adapter, &input, NULL);

if (ACPI_FAILURE(status))
return status;
--
2.25.1

2022-12-08 15:55:48

by Hans de Goede

Subject: Re: [PATCH] platform/x86: mxm-wmi: fix memleak in mxm_wmi_call_mx[ds|mx]()

Hi,

On 11/29/22 02:11, Yu Liao wrote:
> The ACPI buffer memory (out.pointer) returned by wmi_evaluate_method()
> is not freed after the call, so it leads to memory leak.
>
> The method results in ACPI buffer is not used, so just pass NULL to
> wmi_evaluate_method() which fixes the memory leak.
>
> Fixes: 99b38b4acc0d ("platform/x86: add MXM WMI driver.")
> Signed-off-by: Yu Liao <[email protected]>

Thank you for your patch, I've applied this patch 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 my review-hans branch once I've pushed my
local branch there, which might take a while.

Once I've run some tests on this branch the patches there will be
added to the platform-drivers-x86/for-next branch and eventually
will be included in the pdx86 pull-request to Linus for the next
merge-window.

Regards,

Hans



> ---
> drivers/platform/x86/mxm-wmi.c | 8 ++------
> 1 file changed, 2 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/platform/x86/mxm-wmi.c b/drivers/platform/x86/mxm-wmi.c
> index 9a19fbd2f734..9a457956025a 100644
> --- a/drivers/platform/x86/mxm-wmi.c
> +++ b/drivers/platform/x86/mxm-wmi.c
> @@ -35,13 +35,11 @@ int mxm_wmi_call_mxds(int adapter)
> .xarg = 1,
> };
> struct acpi_buffer input = { (acpi_size)sizeof(args), &args };
> - struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
> acpi_status status;
>
> printk("calling mux switch %d\n", adapter);
>
> - status = wmi_evaluate_method(MXM_WMMX_GUID, 0x0, adapter, &input,
> - &output);
> + status = wmi_evaluate_method(MXM_WMMX_GUID, 0x0, adapter, &input, NULL);
>
> if (ACPI_FAILURE(status))
> return status;
> @@ -60,13 +58,11 @@ int mxm_wmi_call_mxmx(int adapter)
> .xarg = 1,
> };
> struct acpi_buffer input = { (acpi_size)sizeof(args), &args };
> - struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
> acpi_status status;
>
> printk("calling mux switch %d\n", adapter);
>
> - status = wmi_evaluate_method(MXM_WMMX_GUID, 0x0, adapter, &input,
> - &output);
> + status = wmi_evaluate_method(MXM_WMMX_GUID, 0x0, adapter, &input, NULL);
>
> if (ACPI_FAILURE(status))
> return status;