Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760145AbXLLUs5 (ORCPT ); Wed, 12 Dec 2007 15:48:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754687AbXLLUst (ORCPT ); Wed, 12 Dec 2007 15:48:49 -0500 Received: from saraswathi.solana.com ([198.99.130.12]:40745 "EHLO saraswathi.solana.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752413AbXLLUss (ORCPT ); Wed, 12 Dec 2007 15:48:48 -0500 Date: Wed, 12 Dec 2007 15:47:59 -0500 From: Jeff Dike To: Andrew Morton Cc: LKML , uml-devel Subject: [PATCH 4/6] UML - Don't allow processes to call into stub Message-ID: <20071212204759.GA9134@c2.user-mode-linux.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.2.3i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1285 Lines: 31 Kill a process that tries to branch into a stub and execute a system call. There are no security implications here - a system call in a stub is treated the same as a system call anywhere else. But if a process is trying to branch into a stub, either it is trying something nasty or it has gone haywire, so it's a good idea to get rid of it in either case. Signed-off-by: Jeff Dike --- arch/um/os-Linux/skas/process.c | 3 +++ 1 file changed, 3 insertions(+) Index: linux-2.6.22/arch/um/os-Linux/skas/process.c =================================================================== --- linux-2.6.22.orig/arch/um/os-Linux/skas/process.c 2007-12-05 12:51:53.000000000 -0500 +++ linux-2.6.22/arch/um/os-Linux/skas/process.c 2007-12-05 16:34:55.000000000 -0500 @@ -146,6 +146,9 @@ static void handle_trap(int pid, struct { int err, status; + if ((UPT_IP(regs) >= STUB_START) && (UPT_IP(regs) < STUB_END)) + fatal_sigsegv(); + /* Mark this as a syscall */ UPT_SYSCALL_NR(regs) = PT_SYSCALL_NR(regs->gp); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/