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=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 CC089C47082 for ; Sat, 5 Jun 2021 09:10:11 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 300E0613E9 for ; Sat, 5 Jun 2021 09:10:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 300E0613E9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 50C046B0036; Sat, 5 Jun 2021 05:10:10 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 4E2756B006C; Sat, 5 Jun 2021 05:10:10 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3AA056B006E; Sat, 5 Jun 2021 05:10:10 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0215.hostedemail.com [216.40.44.215]) by kanga.kvack.org (Postfix) with ESMTP id 0E6586B0036 for ; Sat, 5 Jun 2021 05:10:10 -0400 (EDT) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 9512F9414 for ; Sat, 5 Jun 2021 09:10:09 +0000 (UTC) X-FDA: 78219098538.28.47AD978 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf14.hostedemail.com (Postfix) with ESMTP id 19CA1C0201C6 for ; Sat, 5 Jun 2021 09:10:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=ScPrT6dq7UFJNtAcHi3Kbb1lZ9AVwXDNeiWLjZz5Hno=; b=IFknYVnj7BNmGV8UkYrFPHR9go /U25Wt3qA+aBjWwinMkr5ZcaL1blgrRaaHgmmrJyaI9Mq3Hw49qyfEmiX4BsHyjMiAf9sHDi/UoiM 1IYGGWy+hKDlGkUOAKIZQbSaMtX0jPuT9EIfvlVsMZ/qi/Z4owJpy4ssubuG8GC+36l07hoqB4wRD QSgHGtOGMwJ8pcdWyABdGQW4aostYqvZdGiDPnWrk/KVAq3SBiJF/myIXMevkQJjhmHx1w+5z/ReN lnbtmUQsWFoBe4dNhvF6D5PL3/vdFk/RojcdILzRK8qP9t05CwrAfOWO/+Cmpf/ebqVnPLWhuCMIU 6iZBFu6w==; Received: from willy by casper.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1lpDju-00DQyc-GU; Fri, 04 Jun 2021 17:36:13 +0000 Date: Fri, 4 Jun 2021 18:36:10 +0100 From: Matthew Wilcox To: Hugh Dickins Cc: Andrew Morton , "Kirill A. Shutemov" , Yang Shi , Wang Yugui , Naoya Horiguchi , Alistair Popple , Ralph Campbell , Zi Yan , Miaohe Lin , Minchan Kim , Jue Wang , Peter Xu , Jan Kara , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 3/7] mm/thp: fix vma_address() if virtual address below file offset Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 19CA1C0201C6 Authentication-Results: imf14.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=IFknYVnj; dmarc=none; spf=none (imf14.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org X-Stat-Signature: xhedw4qmth6xy7e736e73eqdnhuyomtw X-HE-Tag: 1622884206-53989 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Jun 03, 2021 at 02:40:30PM -0700, Hugh Dickins wrote: > static inline unsigned long > -__vma_address(struct page *page, struct vm_area_struct *vma) > +vma_address(struct page *page, struct vm_area_struct *vma) > { > - pgoff_t pgoff = page_to_pgoff(page); > - return vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); > + pgoff_t pgoff; > + unsigned long address; > + > + VM_BUG_ON_PAGE(PageKsm(page), page); /* KSM page->index unusable */ > + pgoff = page_to_pgoff(page); > + if (pgoff >= vma->vm_pgoff) { > + address = vma->vm_start + > + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); > + /* Check for address beyond vma (or wrapped through 0?) */ > + if (address < vma->vm_start || address >= vma->vm_end) > + address = -EFAULT; > + } else if (PageHead(page) && > + pgoff + compound_nr(page) > vma->vm_pgoff) { I think on 32-bit, you need ... pgoff + compound_nr(page) - 1 >= vma->vm_pgoff ... right? > + address = vma->vm_start; > + } else { > + address = -EFAULT; > + } > + return address; > }