From: Andrew Morton <akpm@osdl.org>
Date: Mon, 12 Feb 2007 08:51:43 +0000 (-0800)
Subject: [PATCH] register_chrdev_region() don't hand out the LOCAL/EXPERIMENTAL majors
X-Git-Tag: v2.6.21-rc1~274^2~206
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=215122e1110f97a3f478829049b9840cf8fdde57;p=linux-2.6

[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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/fs/char_dev.c b/fs/char_dev.c
index a885f46ca0..e6194e2b9b 100644
--- a/fs/char_dev.c
+++ b/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;
 		}