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 X-Spam-Level: X-Spam-Status: No, score=-15.8 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 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 AB099C433F5 for ; Thu, 2 Sep 2021 21:58:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 90C0A60F12 for ; Thu, 2 Sep 2021 21:58:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347955AbhIBV70 (ORCPT ); Thu, 2 Sep 2021 17:59:26 -0400 Received: from mail.kernel.org ([198.145.29.99]:54992 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347683AbhIBV7V (ORCPT ); Thu, 2 Sep 2021 17:59:21 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C3D1A60F12; Thu, 2 Sep 2021 21:58:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1630619903; bh=S9YjKxtcJFESm+xz/VkwLPcKBtuPlNLYGpGGjWla9lI=; h=Date:From:To:Subject:In-Reply-To:From; b=jGlyty/uJFPiSMPsB3BRC91dq954gfb52FkhchjAYskY2G5QGjvI9IQDm++V9/YiK RfxORc8zPKt2aP3HbFhZnOZVzFoCZ7UuGf7aFMxVpVFqxvh068jxTDop/e9cHZ90Qa +e5dIgYLq3Sjscm7DF8mqBRQKreuyKO1zloIC4gU= Date: Thu, 02 Sep 2021 14:58:22 -0700 From: Andrew Morton To: akpm@linux-foundation.org, linmiaohe@huawei.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, naoya.horiguchi@nec.com, torvalds@linux-foundation.org Subject: [patch 159/212] mm/hwpoison: fix potential pte_unmap_unlock pte error Message-ID: <20210902215822.jKdOK27-5%akpm@linux-foundation.org> In-Reply-To: <20210902144820.78957dff93d7bea620d55a89@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Miaohe Lin Subject: mm/hwpoison: fix potential pte_unmap_unlock pte error If the first pte is equal to poisoned_pfn, i.e. check_hwpoisoned_entry() return 1, the wrong ptep - 1 would be passed to pte_unmap_unlock(). Link: https://lkml.kernel.org/r/20210814105131.48814-3-linmiaohe@huawei.com Fixes: ad9c59c24095 ("mm,hwpoison: send SIGBUS with error virutal address") Signed-off-by: Miaohe Lin Acked-by: Naoya Horiguchi Signed-off-by: Andrew Morton --- mm/memory-failure.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/mm/memory-failure.c~mm-hwpoison-fix-potential-pte_unmap_unlock-pte-error +++ a/mm/memory-failure.c @@ -632,7 +632,7 @@ static int hwpoison_pte_range(pmd_t *pmd { struct hwp_walk *hwp = (struct hwp_walk *)walk->private; int ret = 0; - pte_t *ptep; + pte_t *ptep, *mapped_pte; spinlock_t *ptl; ptl = pmd_trans_huge_lock(pmdp, walk->vma); @@ -645,14 +645,15 @@ static int hwpoison_pte_range(pmd_t *pmd if (pmd_trans_unstable(pmdp)) goto out; - ptep = pte_offset_map_lock(walk->vma->vm_mm, pmdp, addr, &ptl); + mapped_pte = ptep = pte_offset_map_lock(walk->vma->vm_mm, pmdp, + addr, &ptl); for (; addr != end; ptep++, addr += PAGE_SIZE) { ret = check_hwpoisoned_entry(*ptep, addr, PAGE_SHIFT, hwp->pfn, &hwp->tk); if (ret == 1) break; } - pte_unmap_unlock(ptep - 1, ptl); + pte_unmap_unlock(mapped_pte, ptl); out: cond_resched(); return ret; _