scsi: mpt3sas: Fix error return code of mpt3sas_base_attach()

When kzalloc() returns NULL, no error return code of mpt3sas_base_attach()
is assigned. To fix this bug, r is assigned with -ENOMEM in this case.

Link: https://lore.kernel.org/r/20210308035241.3288-1-baijiaju1990@gmail.com
Fixes: c696f7b ("scsi: mpt3sas: Implement device_remove_in_progress check in IOCTL path")
Reported-by: TOTE Robot <oslab@tsinghua.edu.cn>
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/mpt3sas/mpt3sas_base.c

@@ -7806,14 +7806,18 @@ mpt3sas_base_attach(struct MPT3SAS_ADAPTER *ioc)
 		ioc->pend_os_device_add_sz++;
 	ioc->pend_os_device_add = kzalloc(ioc->pend_os_device_add_sz,
 	    GFP_KERNEL);
-	if (!ioc->pend_os_device_add)
+	if (!ioc->pend_os_device_add) {
+		r = -ENOMEM;
 		goto out_free_resources;
+	}
 
 	ioc->device_remove_in_progress_sz = ioc->pend_os_device_add_sz;
 	ioc->device_remove_in_progress =
 		kzalloc(ioc->device_remove_in_progress_sz, GFP_KERNEL);
-	if (!ioc->device_remove_in_progress)
+	if (!ioc->device_remove_in_progress) {
+		r = -ENOMEM;
 		goto out_free_resources;
+	}
 
 	ioc->fwfault_debug = mpt3sas_fwfault_debug;