[S390] cio: fix use after free in s390 debug feature
When using s390dbf with "%s" in sprintf format strings the string itself
is not copied to the dbf buffer.
Since in this case only pointers are stored in the s390dbf, we should
not use dev_name - which is bound to the lifetime of the device.
Reading this entry from s390dbf after the device was released will cause
an use after free error.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index a50cfa5..6b770f8 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -2038,7 +2038,9 @@
spin_unlock_irq(sch->lock);
if (ret) {
CIO_MSG_EVENT(0, "Couldn't start recognition for device "
- "%s (ret=%d)\n", dev_name(&cdev->dev), ret);
+ "0.%x.%04x (ret=%d)\n",
+ cdev->private->dev_id.ssid,
+ cdev->private->dev_id.devno, ret);
spin_lock_irq(sch->lock);
cdev->private->state = DEV_STATE_DISCONNECTED;
spin_unlock_irq(sch->lock);
@@ -2101,8 +2103,9 @@
}
/* check if the device id has changed */
if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
- CIO_MSG_EVENT(0, "resume: sch %s: failed (devno changed from "
- "%04x to %04x)\n", dev_name(&sch->dev),
+ CIO_MSG_EVENT(0, "resume: sch 0.%x.%04x: failed (devno "
+ "changed from %04x to %04x)\n",
+ sch->schid.ssid, sch->schid.sch_no,
cdev->private->dev_id.devno,
sch->schib.pmcw.dev);
goto out_unreg_unlock;
@@ -2135,8 +2138,9 @@
if (cm_enabled) {
ret = ccw_set_cmf(cdev, 1);
if (ret) {
- CIO_MSG_EVENT(2, "resume: cdev %s: cmf failed "
- "(rc=%d)\n", dev_name(&cdev->dev), ret);
+ CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
+ "(rc=%d)\n", cdev->private->dev_id.ssid,
+ cdev->private->dev_id.devno, ret);
ret = 0;
}
}