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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 0AAD5C433E1 for ; Thu, 20 Aug 2020 10:26:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D625220738 for ; Thu, 20 Aug 2020 10:26:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597919173; bh=0ETO/R8vx8r+dQSD3C/4hIPkA1h9Zp+nM/phIiVQ3Kg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=giED8wngK20LzCAVn2mcui0FhradFmSoM5FSpuG+l0Br1rkEwzqgp6iNNyE1hNcxm sVhS/PobUE1hupkImnTUfZqC/XHg5ZRLMNUjwwM8jdvsEiaXSLvbIheKxl3vi4xATe xtjaFIX94X5vRKj/zEW321fUIc+DmusAIiK7emKw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731717AbgHTK0M (ORCPT ); Thu, 20 Aug 2020 06:26:12 -0400 Received: from mail.kernel.org ([198.145.29.99]:52072 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731696AbgHTKXJ (ORCPT ); Thu, 20 Aug 2020 06:23:09 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.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 45DFD2075E; Thu, 20 Aug 2020 10:23:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597918988; bh=0ETO/R8vx8r+dQSD3C/4hIPkA1h9Zp+nM/phIiVQ3Kg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KijWR/THG7VOzHYlshjEMu8D0y3cEaLABycbhuKfSVl+SlPYR/317Zk4htSQWa7iM KE6O/CdXCE0/uBYVfl7lNWYTxZZqoAQSZJhAQqEYsMZkkPBPLhI1CNfZJYuk4TaZ82 5n2GXPR9zqoJZE1aqCEL7WmMT8sHvI0GtG7PPKS8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jeffrey Mitchell , Trond Myklebust , Sasha Levin Subject: [PATCH 4.4 143/149] nfs: Fix getxattr kernel panic and memory overflow Date: Thu, 20 Aug 2020 11:23:40 +0200 Message-Id: <20200820092132.622121151@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200820092125.688850368@linuxfoundation.org> References: <20200820092125.688850368@linuxfoundation.org> User-Agent: quilt/0.66 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 From: Jeffrey Mitchell [ Upstream commit b4487b93545214a9db8cbf32e86411677b0cca21 ] Move the buffer size check to decode_attr_security_label() before memcpy() Only call memcpy() if the buffer is large enough Fixes: aa9c2669626c ("NFS: Client implementation of Labeled-NFS") Signed-off-by: Jeffrey Mitchell [Trond: clean up duplicate test of label->len != 0] Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin --- fs/nfs/nfs4proc.c | 2 -- fs/nfs/nfs4xdr.c | 6 +++++- 2 files changed, 5 insertions(+), 3 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 566afcc36adb5..ca1702cefb852 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -4916,8 +4916,6 @@ static int _nfs4_get_security_label(struct inode *inode, void *buf, return ret; if (!(fattr.valid & NFS_ATTR_FATTR_V4_SECURITY_LABEL)) return -ENOENT; - if (buflen < label.len) - return -ERANGE; return 0; } diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c index 15cd9db6d616d..28c1b765e4444 100644 --- a/fs/nfs/nfs4xdr.c +++ b/fs/nfs/nfs4xdr.c @@ -4158,7 +4158,11 @@ static int decode_attr_security_label(struct xdr_stream *xdr, uint32_t *bitmap, goto out_overflow; if (len < NFS4_MAXLABELLEN) { if (label) { - memcpy(label->label, p, len); + if (label->len) { + if (label->len < len) + return -ERANGE; + memcpy(label->label, p, len); + } label->len = len; label->pi = pi; label->lfs = lfs; -- 2.25.1