scsi: snic: Fix double free in snic_tgt_create()

Commit 41320b1 ("scsi: snic: Fix possible memory leak if device_add()
fails") fixed the memory leak caused by dev_set_name() when device_add()
failed. However, it did not consider that 'tgt' has already been released
when put_device(&tgt->dev) is called. Remove kfree(tgt) in the error path
to avoid double free of 'tgt' and move put_device(&tgt->dev) after the
removed kfree(tgt) to avoid a use-after-free.

Fixes: 41320b1 ("scsi: snic: Fix possible memory leak if device_add() fails")
Signed-off-by: Zhu Wang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Martin K. Petersen <[email protected]>

Author: PeterZhu789

drivers/scsi/snic/snic_disc.c

@@ -303,12 +303,11 @@ snic_tgt_create(struct snic *snic, struct snic_tgt_id *tgtid)
 			      "Snic Tgt: device_add, with err = %d\n",
 			      ret);
 
-		put_device(&tgt->dev);
 		put_device(&snic->shost->shost_gendev);
 		spin_lock_irqsave(snic->shost->host_lock, flags);
 		list_del(&tgt->list);
 		spin_unlock_irqrestore(snic->shost->host_lock, flags);
-		kfree(tgt);
+		put_device(&tgt->dev);
 		tgt = NULL;
 
 		return tgt;