[PATCH] register_chrdev_region() don't hand out the LOCAL/EXPERIMENTAL majors

As pointed out in http://bugzilla.kernel.org/show_bug.cgi?id=7922, dynamic
chardev major allocation can hand out majors which LANANA has defined as being
for local/experimental use.

Cc: Torben Mathiasen <device@lanana.org>
Cc: Greg KH <greg@kroah.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Tomas Klas <tomas.klas@mepatek.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/char_dev.c

@@ -108,6 +108,13 @@ __register_chrdev_region(unsigned int major, unsigned int baseminor,
 	/* temporary */
 	if (major == 0) {
 		for (i = ARRAY_SIZE(chrdevs)-1; i > 0; i--) {
+			/*
+			 * Disallow the LANANA-assigned LOCAL/EXPERIMENTAL
+			 * majors
+			 */
+			if ((60 <= i && i <= 63) || (120 <= i && i <= 127) ||
+					(240 <= i && i <= 254))
+				continue;
 			if (chrdevs[i] == NULL)
 				break;
 		}