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=-7.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,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 7143FC43441 for ; Thu, 29 Nov 2018 14:20:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3724E21104 for ; Thu, 29 Nov 2018 14:20:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="TObjm8fd" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3724E21104 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731285AbeK3BZd (ORCPT ); Thu, 29 Nov 2018 20:25:33 -0500 Received: from mail.kernel.org ([198.145.29.99]:49088 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731270AbeK3BZc (ORCPT ); Thu, 29 Nov 2018 20:25:32 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 245A821104; Thu, 29 Nov 2018 14:20:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1543501201; bh=5RB+Ge78ujoLgfRhw2DPUxe/6ymReWdIoDcPEcLiNQE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TObjm8fdKmxPOrdUH0V/yBOj+7dzj6J+QqmfdGcvRAMBtLLk626gm6L5WohgD2ev7 vg2dX+/Bq1T4xGG3zHnX2eG2WkMb0bl4/u1VhvlrS9vfo+Tvs+DRcCFFag7/z+EzBg HILBw2zuOp8Pu6f3Zmit9vaIpya8gdgRc4886UPU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Janosch Frank , David Hildenbrand , Dan Carpenter Subject: [PATCH 4.4 85/86] s390/mm: Check for valid vma before zapping in gmap_discard Date: Thu, 29 Nov 2018 15:12:50 +0100 Message-Id: <20181129140116.504805310@linuxfoundation.org> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181129140109.832117862@linuxfoundation.org> References: <20181129140109.832117862@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Janosch Frank commit 1843abd03250115af6cec0892683e70cf2297c25 upstream. Userspace could have munmapped the area before doing unmapping from the gmap. This would leave us with a valid vmaddr, but an invalid vma from which we would try to zap memory. Let's check before using the vma. Fixes: 1e133ab296f3 ("s390/mm: split arch/s390/mm/pgtable.c") Signed-off-by: Janosch Frank Reviewed-by: David Hildenbrand Reported-by: Dan Carpenter Message-Id: <20180816082432.78828-1-frankja@linux.ibm.com> Signed-off-by: Janosch Frank Signed-off-by: Greg Kroah-Hartman --- arch/s390/mm/pgtable.c | 2 ++ 1 file changed, 2 insertions(+) --- a/arch/s390/mm/pgtable.c +++ b/arch/s390/mm/pgtable.c @@ -637,6 +637,8 @@ void gmap_discard(struct gmap *gmap, uns vmaddr |= gaddr & ~PMD_MASK; /* Find vma in the parent mm */ vma = find_vma(gmap->mm, vmaddr); + if (!vma) + continue; size = min(to - gaddr, PMD_SIZE - (gaddr & ~PMD_MASK)); zap_page_range(vma, vmaddr, size, NULL); }