scsi: mvsas: mv_sas.c: Fix for possible null pointer dereference

There is otherwise a risk of a possible null pointer dereference.

Was largely found by using a static code analysis program called cppcheck.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 14 insertions, 10 deletions

diff --git a/drivers/scsi/mvsas/mv_sas.c b/drivers/scsi/mvsas/mv_sas.c
index 6c1f223a8e1d..ac52f7c99513 100644
--- a/drivers/scsi/mvsas/mv_sas.c
+++ b/drivers/scsi/mvsas/mv_sas.c
@@ -1344,19 +1344,23 @@ void mvs_dev_gone_notify(struct domain_device *dev)
 {
         unsigned long flags = 0;
         struct mvs_device *mvi_dev = dev->lldd_dev;
-        struct mvs_info *mvi = mvi_dev->mvi_info;
-
-        spin_lock_irqsave(&mvi->lock, flags);
+        struct mvs_info *mvi;
 
-        if (mvi_dev) {
-                mv_dprintk("found dev[%d:%x] is gone.\n",
-                        mvi_dev->device_id, mvi_dev->dev_type);
-                mvs_release_task(mvi, dev);
-                mvs_free_reg_set(mvi, mvi_dev);
-                mvs_free_dev(mvi_dev);
-        } else {
+        if (!mvi_dev) {
                 mv_dprintk("found dev has gone.\n");
+                return;
         }
+
+        mvi = mvi_dev->mvi_info;
+
+        spin_lock_irqsave(&mvi->lock, flags);
+
+        mv_dprintk("found dev[%d:%x] is gone.\n",
+                mvi_dev->device_id, mvi_dev->dev_type);
+        mvs_release_task(mvi, dev);
+        mvs_free_reg_set(mvi, mvi_dev);
+        mvs_free_dev(mvi_dev);
+
         dev->lldd_dev = NULL;
         mvi_dev->sas_device = NULL;