From patchwork Fri May 13 14:23:58 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 572506 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 CDB9BC433EF for ; Fri, 13 May 2022 14:32:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1381129AbiEMOcJ (ORCPT ); Fri, 13 May 2022 10:32:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46768 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1381092AbiEMOan (ORCPT ); Fri, 13 May 2022 10:30:43 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C65E360B84; Fri, 13 May 2022 07:28:22 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 6CC59B8306C; Fri, 13 May 2022 14:28:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8619FC34100; Fri, 13 May 2022 14:28:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1652452100; bh=v8J2OCyu1oXEQFYPXvhQXRaH7SZLEAzRz12sZR131bE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dtaqVebBwkRIgipVmjMpIUAS8af9RZR6gt541WyyLmKwulCrUrt85vhM/QLJ6PiQH 5FKAy3AI+dMxoHx6JGt4L98pEKizPYSWyUkcm9GniqayQRdpD60Xk14i5KUDD9t4e1 b2PH2GOINK390uq6rN5y4VRbzc0hbTObr0OnrS7Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Muchun Song , Mike Kravetz , Axel Rasmussen , David Rientjes , Fam Zheng , "Kirill A. Shutemov" , Lars Persson , Peter Xu , Xiongchun Duan , Zi Yan , Andrew Morton , Linus Torvalds Subject: [PATCH 5.15 16/21] mm: hugetlb: fix missing cache flush in copy_huge_page_from_user() Date: Fri, 13 May 2022 16:23:58 +0200 Message-Id: <20220513142230.347129253@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220513142229.874949670@linuxfoundation.org> References: <20220513142229.874949670@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Muchun Song commit e763243cc6cb1fcc720ec58cfd6e7c35ae90a479 upstream. userfaultfd calls copy_huge_page_from_user() which does not do any cache flushing for the target page. Then the target page will be mapped to the user space with a different address (user address), which might have an alias issue with the kernel address used to copy the data from the user to. Fix this issue by flushing dcache in copy_huge_page_from_user(). Link: https://lkml.kernel.org/r/20220210123058.79206-4-songmuchun@bytedance.com Fixes: fa4d75c1de13 ("userfaultfd: hugetlbfs: add copy_huge_page_from_user for hugetlb userfaultfd support") Signed-off-by: Muchun Song Reviewed-by: Mike Kravetz Cc: Axel Rasmussen Cc: David Rientjes Cc: Fam Zheng Cc: Kirill A. Shutemov Cc: Lars Persson Cc: Peter Xu Cc: Xiongchun Duan Cc: Zi Yan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- mm/memory.c | 2 ++ 1 file changed, 2 insertions(+) --- a/mm/memory.c +++ b/mm/memory.c @@ -5467,6 +5467,8 @@ long copy_huge_page_from_user(struct pag if (rc) break; + flush_dcache_page(subpage); + cond_resched(); } return ret_val;