staging: ozwpan: prevent overflow in oz_cdev_write()

We need to check "count" so we don't overflow the ei->data buffer. Reported-by: Nico Golde <[email protected]> Reported-by: Fabian Yamaguchi <[email protected]> Signed-off-by: Dan Carpenter <[email protected]> Cc: [email protected] Signed-off-by: Linus Torvalds <[email protected]>
levisjani · Oct 30, 2013 · c2c65cd · c2c65cd
1 parent 201f99f
commit c2c65cd
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/drivers/staging/ozwpan/ozcdev.c b/drivers/staging/ozwpan/ozcdev.c
@@ -155,6 +155,9 @@ static ssize_t oz_cdev_write(struct file *filp, const char __user *buf,
 	struct oz_app_hdr *app_hdr;
 	struct oz_serial_ctx *ctx;
 
+	if (count > sizeof(ei->data) - sizeof(*elt) - sizeof(*app_hdr))
+		return -EINVAL;
+
 	spin_lock_bh(&g_cdev.lock);
 	pd = g_cdev.active_pd;
 	if (pd)