s390/cio: Use scnprintf() instead of sprintf()

Use scnprintf() instead of sprintf() for those cases where the destination
is an array and the size of the array is known at compile time.

This prevents theoretical buffer overflows, but also avoids that people
again and again spend time to figure out if the code is actually safe.

Reviewed-by: Jan Polensky <[e-mail]>
Signed-off-by: Heiko Carstens <[e-mail]>

drivers/s390/cio/ccwgroup.c

···
 	char str[16];
 
 	for (i = 0; i < gdev->count; i++) {
-		sprintf(str, "cdev%d", i);
+		scnprintf(str, sizeof(str), "cdev%d", i);
 		sysfs_remove_link(&gdev->dev.kobj, str);
 		sysfs_remove_link(&gdev->cdev[i]->dev.kobj, "group_device");
 	}
···
 		}
 	}
 	for (i = 0; i < gdev->count; i++) {
-		sprintf(str, "cdev%d", i);
+		scnprintf(str, sizeof(str), "cdev%d", i);
 		rc = sysfs_create_link(&gdev->dev.kobj,
 				       &gdev->cdev[i]->dev.kobj, str);
 		if (rc) {
 			while (i--) {
-				sprintf(str, "cdev%d", i);
+				scnprintf(str, sizeof(str), "cdev%d", i);
 				sysfs_remove_link(&gdev->dev.kobj, str);
 			}
 			for (i = 0; i < gdev->count; i++)

drivers/s390/cio/chp.c

···
 	char dbf_text[15];
 	int status;
 
-	sprintf(dbf_text, on?"varyon%x.%02x":"varyoff%x.%02x", chpid.cssid,
-		chpid.id);
+	scnprintf(dbf_text, sizeof(dbf_text),
+		  on ? "varyon%x.%02x" : "varyoff%x.%02x",
+		  chpid.cssid, chpid.id);
 	CIO_TRACE_EVENT(2, dbf_text);
 
 	status = chp_get_status(chpid);

drivers/s390/cio/chsc.c

···
 	struct chp_link link;
 	char dbf_txt[15];
 
-	sprintf(dbf_txt, "chpr%x.%02x", chpid.cssid, chpid.id);
+	scnprintf(dbf_txt, sizeof(dbf_txt), "chpr%x.%02x", chpid.cssid, chpid.id);
 	CIO_TRACE_EVENT(2, dbf_txt);
 
 	if (chp_get_status(chpid) <= 0)
···
 {
 	char dbf_txt[15];
 
-	sprintf(dbf_txt, "accpr%x.%02x", link->chpid.cssid,
-		link->chpid.id);
+	scnprintf(dbf_txt, sizeof(dbf_txt), "accpr%x.%02x", link->chpid.cssid,
+		  link->chpid.id);
 	CIO_TRACE_EVENT( 2, dbf_txt);
 	if (link->fla != 0) {
-		sprintf(dbf_txt, "fla%x", link->fla);
+		scnprintf(dbf_txt, sizeof(dbf_txt), "fla%x", link->fla);
 		CIO_TRACE_EVENT( 2, dbf_txt);
 	}
 	/* Wait until previous actions have settled. */
···
 	struct chp_link link;
 	char dbf_txt[15];
 
-	sprintf(dbf_txt, "cadd%x.%02x", chpid.cssid, chpid.id);
+	scnprintf(dbf_txt, sizeof(dbf_txt), "cadd%x.%02x", chpid.cssid, chpid.id);
 	CIO_TRACE_EVENT(2, dbf_txt);
 
 	if (chp_get_status(chpid) != 0) {

drivers/s390/cio/cio.c

···
 	if (cio_update_schib(sch))
 		return -ENODEV;
 
-	sprintf(dbf_text, "no%s", dev_name(&sch->dev));
+	scnprintf(dbf_text, sizeof(dbf_text), "no%s", dev_name(&sch->dev));
 	CIO_TRACE_EVENT(0, dbf_text);
 	CIO_HEX_EVENT(0, &sch->schib, sizeof (struct schib));
 

drivers/s390/cio/device_status.c

···
 		      cdev->private->dev_id.devno, sch->schid.ssid,
 		      sch->schid.sch_no,
 		      scsw_dstat(&irb->scsw), scsw_cstat(&irb->scsw));
-	sprintf(dbf_text, "chk%x", sch->schid.sch_no);
+	scnprintf(dbf_text, sizeof(dbf_text), "chk%x", sch->schid.sch_no);
 	CIO_TRACE_EVENT(0, dbf_text);
 	CIO_HEX_EVENT(0, irb, sizeof(struct irb));
 }