platform/x86: dell-smbios-wmi: Add missing kfree in error-exit from run_smbios_call

As pointed out be Kees Cook if we return -EIO because the
obj->type != ACPI_TYPE_BUFFER, then we must kfree the
output buffer before the return.

Fixes: 1a258e670434 ("platform/x86: dell-smbios-wmi: Add new WMI dispatcher driver")
Reported-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210826140822.71198-1-hdegoede@redhat.com

diff --git a/drivers/platform/x86/dell/dell-smbios-wmi.c b/drivers/platform/x86/dell/dell-smbios-wmi.c
index 01ea4bb..931cc50 100644 (file)
--- a/drivers/platform/x86/dell/dell-smbios-wmi.c
+++ b/drivers/platform/x86/dell/dell-smbios-wmi.c
@@ -69,6 +69,7 @@ static int run_smbios_call(struct wmi_device *wdev)
                if (obj->type == ACPI_TYPE_INTEGER)
                        dev_dbg(&wdev->dev, "SMBIOS call failed: %llu\n",
                                obj->integer.value);
+               kfree(output.pointer);
                return -EIO;
        }
        memcpy(input.pointer, obj->buffer.pointer, obj->buffer.length);