s390/vmlogrdr: fix array access in vmlogrdr_open()

Fix check within vmlogrdr_open() if the minor address is not larger
than the number of array elements.

Found with "smatch":

drivers/s390/char/vmlogrdr.c:318 vmlogrdr_open() warn:
  buffer overflow 'sys_ser' 3 <= 3

Acked-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/drivers/s390/char/vmlogrdr.c b/drivers/s390/char/vmlogrdr.c
index 9b3a24e8d3a0e0dfec9ffcbf1757ddd37f66329e..cf31d3321dab86b889b16fa5e3b9b2e433c3992d 100644 (file)
--- a/drivers/s390/char/vmlogrdr.c
+++ b/drivers/s390/char/vmlogrdr.c
@@ -313,7 +313,7 @@ static int vmlogrdr_open (struct inode *inode, struct file *filp)
        int ret;
 
        dev_num = iminor(inode);
-       if (dev_num > MAXMINOR)
+       if (dev_num >= MAXMINOR)
                return -ENODEV;
        logptr = &sys_ser[dev_num];