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

[ Upstream commit 0487d4fc42d7f31a56cfd9e2237f9ebd889e6112 ]

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
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/platform/x86/dell-smbios-wmi.c b/drivers/platform/x86/dell-smbios-wmi.c
index ccccce9b67efeb018187ac3600afbdbbe9111ef9..0ebcf412f6ca028ac852a3a4fcb110cea13e18c4 100644 (file)
--- a/drivers/platform/x86/dell-smbios-wmi.c
+++ b/drivers/platform/x86/dell-smbios-wmi.c
@@ -72,6 +72,7 @@ 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(&priv->buf->std, obj->buffer.pointer, obj->buffer.length);