busybox: cve-2014-9645

modprobe,rmmod: reject module names with slashes

(From OE-Core rev: 815a7b6fbf3b0cf95f5464bca687d97366d7ed6a)

Signed-off-by: Armin Kuster <akuster@mvista.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-core/busybox/busybox/CVE-2014-9645_busybox_reject_module_names_with_slashes.patch

@@ -0,0 +1,41 @@
+Upstream-status: Backport
+http://git.busybox.net/busybox/commit/?id=4e314faa0aecb66717418e9a47a4451aec59262b
+
+CVE-2014-9645 fix.
+
+[YOCTO #7257]
+
+Signed-off-by: Armin Kuster <akuster@mvista.com>
+
+From 4e314faa0aecb66717418e9a47a4451aec59262b Mon Sep 17 00:00:00 2001
+From: Denys Vlasenko <vda.linux@googlemail.com>
+Date: Thu, 20 Nov 2014 17:24:33 +0000
+Subject: modprobe,rmmod: reject module names with slashes
+
+function                                             old     new   delta
+add_probe                                             86     113     +27
+
+Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
+---
+Index: busybox-1.22.1/modutils/modprobe.c
+===================================================================
+--- busybox-1.22.1.orig/modutils/modprobe.c
++++ busybox-1.22.1/modutils/modprobe.c
+@@ -238,6 +238,17 @@ static void add_probe(const char *name)
+ {
+ 	struct module_entry *m;
+ 
++	/*
++	 * get_or_add_modentry() strips path from name and works
++	 * on remaining basename.
++	 * This would make "rmmod dir/name" and "modprobe dir/name"
++	 * to work like "rmmod name" and "modprobe name",
++	 * which is wrong, and can be abused via implicit modprobing:
++	 * "ifconfig /usbserial up" tries to modprobe netdev-/usbserial.
++	 */
++	if (strchr(name, '/'))
++		bb_error_msg_and_die("malformed module name '%s'", name);
++
+ 	m = get_or_add_modentry(name);
+ 	if (!(option_mask32 & (OPT_REMOVE | OPT_SHOW_DEPS))
+ 	 && (m->flags & MODULE_FLAG_LOADED)

meta/recipes-core/busybox/busybox_1.22.1.bb

@@ -33,6 +33,7 @@ SRC_URI = "http://www.busybox.net/downloads/busybox-${PV}.tar.bz2;name=tarball \
            file://0001-build-system-Specify-nostldlib-when-linking-to-.o-fi.patch \
            file://recognize_connmand.patch \
            file://busybox-cross-menuconfig.patch \
+           file://CVE-2014-9645_busybox_reject_module_names_with_slashes.patch \
 "
 
 SRC_URI[tarball.md5sum] = "337d1a15ab1cb1d4ed423168b1eb7d7e"