UBI: bugfix: dont oops with NULL module parameter

E.g., it oopsed in case of: modprobe ubi mtd = 0

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index 9b94427be145..b85ca186afc6 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -845,6 +845,9 @@ static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
         char *pbuf = &buf[0];
         char *tokens[3] = {NULL, NULL, NULL};
 
+        if (!val)
+                return -EINVAL;
+
         if (mtd_devs == UBI_MAX_DEVICES) {
                 printk("UBI error: too many parameters, max. is %d\n",
                        UBI_MAX_DEVICES);