[PATCH] DAC960 fix for NULL dereference in open()

This fixes a problem that's been hidden for a while.

DAC960_open() will try to dereference a NULL pointer if an application
opens (for example) /dev/rd/c0d12 when there has never been a logical
device created for that file.

diff --git a/drivers/block/DAC960.c b/drivers/block/DAC960.c
index ce64803..2f13a50 100644 (file)
--- a/drivers/block/DAC960.c
+++ b/drivers/block/DAC960.c
@@ -82,7 +82,7 @@ static int DAC960_open(struct inode *inode, struct file *file)
        } else {
                DAC960_V2_LogicalDeviceInfo_T *i =
                        p->V2.LogicalDeviceInformation[drive_nr];
-               if (i->LogicalDeviceState == DAC960_V2_LogicalDevice_Offline)
+               if (!i || i->LogicalDeviceState == DAC960_V2_LogicalDevice_Offline)
                        return -ENXIO;
        }