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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 EC32BFA3728 for ; Wed, 16 Oct 2019 22:23:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C352721848 for ; Wed, 16 Oct 2019 22:23:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571264600; bh=OBdtrm8pJtajj5WunNduBtqbGjzE7rTRWzKQSZySMEs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=g4KSm1Nc0QRnRlM7pKtIlqQstje4Kac9M29hvS7MntXNZwHguGzK5WWBS+jd69i5U Plx7/pQD5oakHjgtF15YalavNbp2OOoLgOhyMxqr8Ld3xjL/Zph4lmU/FKMJrgayK9 CLNvCcHy2FCk8k/BrT2sF3PXm6ANtdGDu31bbW5w= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2437083AbfJPVw5 (ORCPT ); Wed, 16 Oct 2019 17:52:57 -0400 Received: from mail.kernel.org ([198.145.29.99]:41276 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2436896AbfJPVwy (ORCPT ); Wed, 16 Oct 2019 17:52:54 -0400 Received: from localhost (unknown [192.55.54.58]) (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 943B420872; Wed, 16 Oct 2019 21:52:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571262772; bh=OBdtrm8pJtajj5WunNduBtqbGjzE7rTRWzKQSZySMEs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fHM4ujKbIn6mUCLxrYbvnoa8XJG8W2rBsVanOR5eRr88b+SU4tTueVGSKq3hj3Qvj 8Q54bCV/nLxG9W+WKhcNFfO0tx2JHbxMOaEQShEwAmUrMdTAafmedS3zynJ5SNxaiI q6YQSz0HnvUNUJvc24+xHcTdoAil8cVeeYX09G/o= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jia-Ju Bai , Anna Schumaker , Sasha Levin Subject: [PATCH 4.4 13/79] fs: nfs: Fix possible null-pointer dereferences in encode_attrs() Date: Wed, 16 Oct 2019 14:49:48 -0700 Message-Id: <20191016214741.602462781@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191016214729.758892904@linuxfoundation.org> References: <20191016214729.758892904@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: Jia-Ju Bai [ Upstream commit e2751463eaa6f9fec8fea80abbdc62dbc487b3c5 ] In encode_attrs(), there is an if statement on line 1145 to check whether label is NULL: if (label && (attrmask[2] & FATTR4_WORD2_SECURITY_LABEL)) When label is NULL, it is used on lines 1178-1181: *p++ = cpu_to_be32(label->lfs); *p++ = cpu_to_be32(label->pi); *p++ = cpu_to_be32(label->len); p = xdr_encode_opaque_fixed(p, label->label, label->len); To fix these bugs, label is checked before being used. These bugs are found by a static analysis tool STCheck written by us. Signed-off-by: Jia-Ju Bai Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin --- fs/nfs/nfs4xdr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c index 1cb50bb898b01..15cd9db6d616d 100644 --- a/fs/nfs/nfs4xdr.c +++ b/fs/nfs/nfs4xdr.c @@ -1123,7 +1123,7 @@ static void encode_attrs(struct xdr_stream *xdr, const struct iattr *iap, } else *p++ = cpu_to_be32(NFS4_SET_TO_SERVER_TIME); } - if (bmval[2] & FATTR4_WORD2_SECURITY_LABEL) { + if (label && (bmval[2] & FATTR4_WORD2_SECURITY_LABEL)) { *p++ = cpu_to_be32(label->lfs); *p++ = cpu_to_be32(label->pi); *p++ = cpu_to_be32(label->len); -- 2.20.1