1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c
index d23f3225b00f..445856c9127a 100644
--- a/drivers/input/misc/uinput.c
+++ b/drivers/input/misc/uinput.c
@@ -417,6 +417,20 @@ static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code,
 		return -EINVAL;
 	}
 
+	/*
+	 * Limit number of contacts to a reasonable value (100). This
+	 * ensures that we need less than 2 pages for struct input_mt
+	 * (we are not using in-kernel slot assignment so not going to
+	 * allocate memory for the "red" table), and we should have no
+	 * trouble getting this much memory.
+	 */
+	if (code == ABS_MT_SLOT && max > 99) {
+		printk(KERN_DEBUG
+		       "%s: unreasonably large number of slots requested: %d\n",
+		       UINPUT_NAME, max);
+		return -EINVAL;
+	}
+
 	return 0;
 }