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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77181E92FDD for ; Fri, 6 Oct 2023 04:00:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229970AbjJFEAo (ORCPT ); Fri, 6 Oct 2023 00:00:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56750 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229968AbjJFEAj (ORCPT ); Fri, 6 Oct 2023 00:00:39 -0400 Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2789CE7 for ; Thu, 5 Oct 2023 21:00:36 -0700 (PDT) Received: from imladris.home.surriel.com ([10.0.13.28] helo=imladris.surriel.com) by shelob.surriel.com with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1qoc0k-0000mf-30; Fri, 06 Oct 2023 00:00:22 -0400 From: riel@surriel.com To: linux-kernel@vger.kernel.org Cc: kernel-team@meta.com, linux-mm@kvack.org, akpm@linux-foundation.org, muchun.song@linux.dev, mike.kravetz@oracle.com, leit@meta.com, willy@infradead.org, Rik van Riel , stable@kernel.org Subject: [PATCH 1/4] hugetlbfs: clear resv_map pointer if mmap fails Date: Thu, 5 Oct 2023 23:59:06 -0400 Message-ID: <20231006040020.3677377-2-riel@surriel.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20231006040020.3677377-1-riel@surriel.com> References: <20231006040020.3677377-1-riel@surriel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: riel@surriel.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rik van Riel Hugetlbfs leaves a dangling pointer in the VMA if mmap fails. This has not been a problem so far, but other code in this patch series tries to follow that pointer. Signed-off-by: Mike Kravetz Signed-off-by: Rik van Riel Cc: stable@kernel.org Fixes: 04ada095dcfc ("hugetlb: don't delete vma_lock in hugetlb MADV_DONTNEED processing") --- mm/hugetlb.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index ba6d39b71cb1..a86e070d735b 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1138,8 +1138,7 @@ static void set_vma_resv_map(struct vm_area_struct *vma, struct resv_map *map) VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma); - set_vma_private_data(vma, (get_vma_private_data(vma) & - HPAGE_RESV_MASK) | (unsigned long)map); + set_vma_private_data(vma, (unsigned long)map); } static void set_vma_resv_flags(struct vm_area_struct *vma, unsigned long flags) @@ -6806,8 +6805,10 @@ bool hugetlb_reserve_pages(struct inode *inode, */ if (chg >= 0 && add < 0) region_abort(resv_map, from, to, regions_needed); - if (vma && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) + if (vma && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { kref_put(&resv_map->refs, resv_map_release); + set_vma_resv_map(vma, NULL); + } return false; } -- 2.41.0