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 A7349C433F5 for ; Wed, 20 Oct 2021 17:45:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 94DBF6128E for ; Wed, 20 Oct 2021 17:45:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231210AbhJTRr1 (ORCPT ); Wed, 20 Oct 2021 13:47:27 -0400 Received: from out01.mta.xmission.com ([166.70.13.231]:43342 "EHLO out01.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231202AbhJTRrP (ORCPT ); Wed, 20 Oct 2021 13:47:15 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]:50228) by out01.mta.xmission.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1mdFe8-00EwIU-Fz; Wed, 20 Oct 2021 11:45:00 -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 1mdFe7-001NdN-FW; Wed, 20 Oct 2021 11:45:00 -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" , David Miller , sparclinux@vger.kernel.org Date: Wed, 20 Oct 2021 12:43:54 -0500 Message-Id: <20211020174406.17889-8-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=1mdFe7-001NdN-FW;;;mid=<20211020174406.17889-8-ebiederm@xmission.com>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1+m7zFDieSDYP9ie4oAgZCOoskjv4SbOX8= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: [PATCH 08/20] signal/sparc: In setup_tsb_params convert open coded BUG into BUG 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 setup_tsb_params has exactly one caller tsb_grow. The function tsb_grow passes in a tsb_bytes value that is between 8192 and 1048576 inclusive, and is guaranteed to be a power of 2. The function setup_tsb_params verifies this property with a switch statement and then prints an error and causes the task to exit if this is not true. In practice that print statement can never be reached because tsb_grow never passes in a bad tsb_size. So if tsb_size ever gets a bad value that is a kernel bug. So replace the do_exit which is effectively an open coded version of BUG() with an actuall call to BUG(). Making it clearer that this is a case that can never, and should never happen. Cc: David Miller Cc: sparclinux@vger.kernel.org Signed-off-by: "Eric W. Biederman" --- arch/sparc/mm/tsb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/sparc/mm/tsb.c b/arch/sparc/mm/tsb.c index 0dce4b7ff73e..912205787161 100644 --- a/arch/sparc/mm/tsb.c +++ b/arch/sparc/mm/tsb.c @@ -266,7 +266,7 @@ static void setup_tsb_params(struct mm_struct *mm, unsigned long tsb_idx, unsign default: printk(KERN_ERR "TSB[%s:%d]: Impossible TSB size %lu, killing process.\n", current->comm, current->pid, tsb_bytes); - do_exit(SIGSEGV); + BUG(); } tte |= pte_sz_bits(page_sz); -- 2.20.1