[S390] dasd: fix possible NULL pointer errors

Fix possible NULL pointer in DASD messages and correct discipline
checking.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

4 files changed, 9 insertions, 15 deletions

diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index fdb2e7c14506..5905936c7c60 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -1004,8 +1004,8 @@ static void dasd_handle_killed_request(struct ccw_device *cdev,
         if (device == NULL ||
             device != dasd_device_from_cdev_locked(cdev) ||
             strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
-                DBF_DEV_EVENT(DBF_DEBUG, device, "invalid device in request: "
-                              "bus_id %s", dev_name(&cdev->dev));
+                DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
+                                "invalid device in request");
                 return;
         }
 
@@ -1078,8 +1078,8 @@ void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
         device = (struct dasd_device *) cqr->startdev;
         if (!device ||
             strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
-                DBF_DEV_EVENT(DBF_DEBUG, device, "invalid device in request: "
-                              "bus_id %s", dev_name(&cdev->dev));
+                DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
+                                "invalid device in request");
                 return;
         }
 
diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
index 1c500c462225..1cca21aafaba 100644
--- a/drivers/s390/block/dasd_eckd.c
+++ b/drivers/s390/block/dasd_eckd.c
@@ -3033,7 +3033,7 @@ static void dasd_eckd_dump_sense_ccw(struct dasd_device *device,
         len += sprintf(page + len, KERN_ERR PRINTK_HEADER
                        " in req: %p CS: 0x%02X DS: 0x%02X CC: 0x%02X RC: %d\n",
                        req, scsw_cstat(&irb->scsw), scsw_dstat(&irb->scsw),
-                       scsw_cc(&irb->scsw), req->intrc);
+                       scsw_cc(&irb->scsw), req ? req->intrc : 0);
         len += sprintf(page + len, KERN_ERR PRINTK_HEADER
                        " device %s: Failing CCW: %p\n",
                        dev_name(&device->cdev->dev),
diff --git a/drivers/s390/block/dasd_ioctl.c b/drivers/s390/block/dasd_ioctl.c
index fc7b30b4a255..7039d9cf0fb4 100644
--- a/drivers/s390/block/dasd_ioctl.c
+++ b/drivers/s390/block/dasd_ioctl.c
@@ -260,7 +260,7 @@ static int dasd_ioctl_information(struct dasd_block *block,
         struct ccw_dev_id dev_id;
 
         base = block->base;
-        if (!base->discipline->fill_info)
+        if (!base->discipline || !base->discipline->fill_info)
                 return -EINVAL;
 
         dasd_info = kzalloc(sizeof(struct dasd_information2_t), GFP_KERNEL);
@@ -303,10 +303,7 @@ static int dasd_ioctl_information(struct dasd_block *block,
         dasd_info->features |=
                 ((base->features & DASD_FEATURE_READONLY) != 0);
 
-        if (base->discipline)
-                memcpy(dasd_info->type, base->discipline->name, 4);
-        else
-                memcpy(dasd_info->type, "none", 4);
+        memcpy(dasd_info->type, base->discipline->name, 4);
 
         if (block->request_queue->request_fn) {
                 struct list_head *l;
diff --git a/drivers/s390/block/dasd_proc.c b/drivers/s390/block/dasd_proc.c
index 6315fbd8e68b..71f95f54866f 100644
--- a/drivers/s390/block/dasd_proc.c
+++ b/drivers/s390/block/dasd_proc.c
@@ -72,7 +72,7 @@ dasd_devices_show(struct seq_file *m, void *v)
         /* Print device number. */
         seq_printf(m, "%s", dev_name(&device->cdev->dev));
         /* Print discipline string. */
-        if (device != NULL && device->discipline != NULL)
+        if (device->discipline != NULL)
                 seq_printf(m, "(%s)", device->discipline->name);
         else
                 seq_printf(m, "(none)");
@@ -92,10 +92,7 @@ dasd_devices_show(struct seq_file *m, void *v)
         substr = (device->features & DASD_FEATURE_READONLY) ? "(ro)" : " ";
         seq_printf(m, "%4s: ", substr);
         /* Print device status information. */
-        switch ((device != NULL) ? device->state : -1) {
-        case -1:
-                seq_printf(m, "unknown");
-                break;
+        switch (device->state) {
         case DASD_STATE_NEW:
                 seq_printf(m, "new");
                 break;