From patchwork Mon Dec 28 12:47:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 355126 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EDC79C433E9 for ; Mon, 28 Dec 2020 13:25:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B9F2022B3B for ; Mon, 28 Dec 2020 13:25:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388839AbgL1NZE (ORCPT ); Mon, 28 Dec 2020 08:25:04 -0500 Received: from mail.kernel.org ([198.145.29.99]:53766 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388835AbgL1NZD (ORCPT ); Mon, 28 Dec 2020 08:25:03 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 96F3F22A84; Mon, 28 Dec 2020 13:24:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1609161862; bh=16ofqNDOtTdD+Nbw3rTnBhytlvP13deUuWsiMlij8zo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=w2KrN+YC1QCi+M1+KmayJaiaKFL95Rb1aMpx5Q3zt+jc1cnJ/UX5C6/nFzPF6gM1b sbGePG5YNJm9pOBjDCuOJ0iIatoUjL1ewNmMyqab8LIc8tsThOwUnsCRZ34z3LaTLk wGzmuUNnzvAAOMBSecEG81GfFbjdhAlTgR/XfvCY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Arvind Sankar , Borislav Petkov , Joerg Roedel , "Kirill A. Shutemov" , Sasha Levin Subject: [PATCH 4.19 107/346] x86/mm/ident_map: Check for errors from ident_pud_init() Date: Mon, 28 Dec 2020 13:47:06 +0100 Message-Id: <20201228124924.958176082@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201228124919.745526410@linuxfoundation.org> References: <20201228124919.745526410@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Arvind Sankar [ Upstream commit 1fcd009102ee02e217f2e7635ab65517d785da8e ] Commit ea3b5e60ce80 ("x86/mm/ident_map: Add 5-level paging support") added ident_p4d_init() to support 5-level paging, but this function doesn't check and return errors from ident_pud_init(). For example, the decompressor stub uses this code to create an identity mapping. If it runs out of pages while trying to allocate a PMD pagetable, the error will be currently ignored. Fix this to propagate errors. [ bp: Space out statements for better readability. ] Fixes: ea3b5e60ce80 ("x86/mm/ident_map: Add 5-level paging support") Signed-off-by: Arvind Sankar Signed-off-by: Borislav Petkov Reviewed-by: Joerg Roedel Acked-by: Kirill A. Shutemov Link: https://lkml.kernel.org/r/20201027230648.1885111-1-nivedita@alum.mit.edu Signed-off-by: Sasha Levin --- arch/x86/mm/ident_map.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/arch/x86/mm/ident_map.c b/arch/x86/mm/ident_map.c index fe7a12599d8eb..968d7005f4a72 100644 --- a/arch/x86/mm/ident_map.c +++ b/arch/x86/mm/ident_map.c @@ -62,6 +62,7 @@ static int ident_p4d_init(struct x86_mapping_info *info, p4d_t *p4d_page, unsigned long addr, unsigned long end) { unsigned long next; + int result; for (; addr < end; addr = next) { p4d_t *p4d = p4d_page + p4d_index(addr); @@ -73,13 +74,20 @@ static int ident_p4d_init(struct x86_mapping_info *info, p4d_t *p4d_page, if (p4d_present(*p4d)) { pud = pud_offset(p4d, 0); - ident_pud_init(info, pud, addr, next); + result = ident_pud_init(info, pud, addr, next); + if (result) + return result; + continue; } pud = (pud_t *)info->alloc_pgt_page(info->context); if (!pud) return -ENOMEM; - ident_pud_init(info, pud, addr, next); + + result = ident_pud_init(info, pud, addr, next); + if (result) + return result; + set_p4d(p4d, __p4d(__pa(pud) | info->kernpg_flag)); }