[PATCH 2/2] platform/x86: dell-smbios-wmi: release mutex lock on WMI call failure

[Mario Limonciello]

Unbound devices may race with calling this function causing the mutex
to stay locked.  This failure mode should have released the mutex too.

Signed-off-by: Mario Limonciello <mario.limoncie...@dell.com>
---
 drivers/platform/x86/dell-smbios-wmi.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/x86/dell-smbios-wmi.c 
b/drivers/platform/x86/dell-smbios-wmi.c
index 35c13815..5cf9b13 100644
--- a/drivers/platform/x86/dell-smbios-wmi.c
+++ b/drivers/platform/x86/dell-smbios-wmi.c
@@ -91,8 +91,10 @@ int dell_smbios_wmi_call(struct calling_interface_buffer 
*buffer)
 
        mutex_lock(&call_mutex);
        priv = get_first_smbios_priv();
-       if (!priv)
-               return -ENODEV;
+       if (!priv) {
+               ret = -ENODEV;
+               goto out_wmi_call;
+       }
 
        size = sizeof(struct calling_interface_buffer);
        difference = priv->req_buf_size - sizeof(u64) - size;
@@ -101,6 +103,7 @@ int dell_smbios_wmi_call(struct calling_interface_buffer 
*buffer)
        memcpy(&priv->buf->std, buffer, size);
        ret = run_smbios_call(priv->wdev);
        memcpy(buffer, &priv->buf->std, size);
+out_wmi_call:
        mutex_unlock(&call_mutex);
 
        return ret;
-- 
2.7.4