scsi_debug: schedule_resp fix input variable check

The function should never be called with cmnd NULL so
put a fat WARN there.
Fix also smatch wraning:
schedule_resp() warn: variable dereferenced before check 'cmnd'

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 3a70683cf9f9015a58f9ff712311c009ba5e3943..faa4ddd8decfb84f8813a8f5ad3cf329b034e16a 100644 (file)
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -3941,13 +3941,20 @@ schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip,
        unsigned long iflags;
        int k, num_in_q, qdepth, inject;
        struct sdebug_queued_cmd *sqcp = NULL;
-       struct scsi_device *sdp = cmnd->device;
+       struct scsi_device *sdp;
+
+       /* this should never happen */
+       if (WARN_ON(!cmnd))
+               return SCSI_MLQUEUE_HOST_BUSY;
 
-       if (NULL == cmnd || NULL == devip) {
-               pr_warn("called with NULL cmnd or devip pointer\n");
+       if (NULL == devip) {
+               pr_warn("called devip == NULL\n");
                /* no particularly good error to report back */
                return SCSI_MLQUEUE_HOST_BUSY;
        }
+
+       sdp = cmnd->device;
+
        if ((scsi_result) && (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts))
                sdev_printk(KERN_INFO, sdp, "%s: non-zero result=0x%x\n",
                            __func__, scsi_result);