From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C00FEC433EF for ; Wed, 20 Oct 2021 17:45:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AA19F6128E for ; Wed, 20 Oct 2021 17:45:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231128AbhJTRrh (ORCPT ); Wed, 20 Oct 2021 13:47:37 -0400 Received: from out03.mta.xmission.com ([166.70.13.233]:57116 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231276AbhJTRrS (ORCPT ); Wed, 20 Oct 2021 13:47:18 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]:52836) by out03.mta.xmission.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1mdFeB-002tMs-4D; Wed, 20 Oct 2021 11:45:03 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95]:47894 helo=localhost.localdomain) by in02.mta.xmission.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1mdFe9-001NdN-QI; Wed, 20 Oct 2021 11:45:02 -0600 From: "Eric W. Biederman" To: linux-kernel@vger.kernel.org Cc: linux-arch@vger.kernel.org, Linus Torvalds , Oleg Nesterov , Al Viro , Kees Cook , "Eric W. Biederman" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, H Peter Anvin Date: Wed, 20 Oct 2021 12:43:55 -0500 Message-Id: <20211020174406.17889-9-ebiederm@xmission.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <87y26nmwkb.fsf@disp2133> References: <87y26nmwkb.fsf@disp2133> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-XM-SPF: eid=1mdFe9-001NdN-QI;;;mid=<20211020174406.17889-9-ebiederm@xmission.com>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1/qfGNFitbP+rEt0PIwwOv9c/FOp0ylaw4= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: [PATCH 09/20] signal/vm86_32: Replace open coded BUG_ON with an actual BUG_ON X-SA-Exim-Version: 4.2.1 (built Sat, 08 Feb 2020 21:53:50 +0000) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The function save_v86_state is only called when userspace was operating in vm86 mode before entering the kernel. Not having vm86 state in the task_struct should never happen. So transform the hand rolled BUG_ON into an actual BUG_ON to make it clear what is happening. Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: x86@kernel.org Cc: H Peter Anvin Signed-off-by: "Eric W. Biederman" --- arch/x86/kernel/vm86_32.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/vm86_32.c b/arch/x86/kernel/vm86_32.c index e5a7a10a0164..63486da77272 100644 --- a/arch/x86/kernel/vm86_32.c +++ b/arch/x86/kernel/vm86_32.c @@ -106,10 +106,8 @@ void save_v86_state(struct kernel_vm86_regs *regs, int retval) */ local_irq_enable(); - if (!vm86 || !vm86->user_vm86) { - pr_alert("no user_vm86: BAD\n"); - do_exit(SIGSEGV); - } + BUG_ON(!vm86 || !vm86->user_vm86); + set_flags(regs->pt.flags, VEFLAGS, X86_EFLAGS_VIF | vm86->veflags_mask); user = vm86->user_vm86; -- 2.20.1