-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 NetBSD Security Advisory 2006-012 ================================= Topic: SIOCGIFALIAS ioctl may cause system crash Version: NetBSD-current: source prior to September 28, 2005 NetBSD 3.0: affected NetBSD 2.1: affected NetBSD 2.0.*: affected NetBSD 2.0: affected NetBSD 1.6.*: affected NetBSD 1.6: affected Severity: Any local user can crash the system Fixed: NetBSD-current: September 28, 2005 NetBSD-3-0 branch: April 02, 2006 (3.0.1 will include the fix) NetBSD-3 branch: April 02, 2006 NetBSD-2-1 branch: April 02, 2006 (2.1.1 will include the fix) NetBSD-2-0 branch: April 02, 2006 (2.0.4 will include the fix) NetBSD-2 branch: April 02, 2006 NetBSD-1-6 branch: April 02, 2006 Abstract ======== A system crash can occur if a user attempts to gather information on a non-existent alias of a network interface via the SIOCGIFALIAS ioctl. Technical Details ================= A NULL dereference occurs in the kernel when the alias in question was not located, rather than returning an error. A socket on the local machine is required. Solutions and Workarounds ========================= For all NetBSD versions, you need to obtain fixed kernel sources, rebuild and install the new kernel, and reboot the system. The fixed source may be obtained from the NetBSD CVS repository. The following instructions briefly summarise how to upgrade your kernel. In these instructions, replace: ARCH with your architecture (from uname -m), and KERNCONF with the name of your kernel configuration file. To update from CVS, re-build, and re-install the kernel: # cd src # cvs update -d -P sys/netinet/in.c # ./build.sh kernel=KERNCONF # mv /netbsd /netbsd.old # cp sys/arch/ARCH/compile/obj/KERNCONF/netbsd /netbsd # shutdown -r now For more information on how to do this, see: http://www.NetBSD.org/guide/en/chap-kernel.html Thanks To ========= Sean Boudreau for PoC code and implementing the fixes. Revision History ================ 2006-04-12 Initial release More Information ================ Advisories may be updated as new information becomes available. The most recent version of this advisory (PGP signed) can be found at ftp://ftp.NetBSD.org/pub/NetBSD/security/advisories/NetBSD-SA2006-012.txt.asc Information about NetBSD and NetBSD security can be found at http://www.NetBSD.org/ and http://www.NetBSD.org/Security/. Copyright 2006, The NetBSD Foundation, Inc. All Rights Reserved. Redistribution permitted only in full, unmodified form. $NetBSD: NetBSD-SA2006-012.txt,v 1.6 2006/04/12 22:09:50 adrianp Exp $ -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.3 (NetBSD) iQCVAwUBRD1+nD5Ru2/4N2IFAQJVdAQAqWpST2Mo4lvYBYAz7LNEpiknkUKjYeGg M8Hp0OQXGLOf0A1fo/Tg4XuGgX7M38meelUpGpvfbMWqPg9AFZFV7JcKylQMnWFH yRMNOJV1GV+25ZzT2pqxpPaGy+jleAW0Q6ZTNa4OsyCQztN8NS6AWMahTY5qmI/i wojlqGVX1N8= =B5UH -----END PGP SIGNATURE-----