From patchwork Sat Jul 6 21:45:42 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ronnie Sahlberg X-Patchwork-Id: 1128539 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-cifs-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 45h4yn62J3z9s7T for ; Sun, 7 Jul 2019 07:45:53 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726734AbfGFVpw (ORCPT ); Sat, 6 Jul 2019 17:45:52 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60398 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726714AbfGFVpw (ORCPT ); Sat, 6 Jul 2019 17:45:52 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B26C63082E0F; Sat, 6 Jul 2019 21:45:51 +0000 (UTC) Received: from test1135.test.redhat.com (vpn2-54-27.bne.redhat.com [10.64.54.27]) by smtp.corp.redhat.com (Postfix) with ESMTP id 14C0280DD; Sat, 6 Jul 2019 21:45:50 +0000 (UTC) From: Ronnie Sahlberg To: linux-cifs Cc: Steve French , Ronnie Sahlberg Subject: [PATCH] cifs: refactor and clean up arguments in the reparse point parsing Date: Sun, 7 Jul 2019 07:45:42 +1000 Message-Id: <20190706214542.1505-1-lsahlber@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.46]); Sat, 06 Jul 2019 21:45:51 +0000 (UTC) Sender: linux-cifs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org Signed-off-by: Ronnie Sahlberg --- fs/cifs/smb2ops.c | 66 ++++++++++++++++++++++++++----------------------------- 1 file changed, 31 insertions(+), 35 deletions(-) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index c4047ad7b43f..4b0b14946343 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -2383,11 +2383,6 @@ parse_reparse_posix(struct reparse_posix_data *symlink_buf, /* See MS-FSCC 2.1.2.6 for the 'NFS' style reparse tags */ len = le16_to_cpu(symlink_buf->ReparseDataLength); - if (len + sizeof(struct reparse_data_buffer) > plen) { - cifs_dbg(VFS, "srv returned malformed symlink buffer\n"); - return -EINVAL; - } - if (le64_to_cpu(symlink_buf->InodeType) != NFS_SPECFILE_LNK) { cifs_dbg(VFS, "%lld not a supported symlink type\n", le64_to_cpu(symlink_buf->InodeType)); @@ -2437,22 +2432,38 @@ parse_reparse_symlink(struct reparse_symlink_data_buffer *symlink_buf, } static int -parse_reparse_point(struct reparse_symlink_data_buffer *buf, - u32 plen, char **target_path, - struct cifs_sb_info *cifs_sb) +parse_reparse_point(struct reparse_data_buffer *buf, + u32 plen, char **target_path, + struct cifs_sb_info *cifs_sb) { - /* See MS-FSCC 2.1.2 */ - if (le32_to_cpu(buf->ReparseTag) == IO_REPARSE_TAG_NFS) - return parse_reparse_posix((struct reparse_posix_data *)buf, - plen, target_path, cifs_sb); - else if (le32_to_cpu(buf->ReparseTag) == IO_REPARSE_TAG_SYMLINK) - return parse_reparse_symlink(buf, plen, target_path, - cifs_sb); + if (plen < sizeof(struct reparse_data_buffer)) { + cifs_dbg(VFS, "reparse buffer is too small. Must be " + "at least 8 bytes but was %d\n", plen); + return -EIO; + } - cifs_dbg(VFS, "srv returned invalid symlink buffer tag:%d\n", - le32_to_cpu(buf->ReparseTag)); + if (plen < le16_to_cpu(buf->ReparseDataLength) + + sizeof(struct reparse_data_buffer)) { + cifs_dbg(VFS, "srv returned invalid reparse buf " + "length: %d\n", plen); + return -EIO; + } - return -EIO; + /* See MS-FSCC 2.1.2 */ + switch (le32_to_cpu(buf->ReparseTag)) { + case IO_REPARSE_TAG_NFS: + return parse_reparse_posix( + (struct reparse_posix_data *)buf, + plen, target_path, cifs_sb); + case IO_REPARSE_TAG_SYMLINK: + return parse_reparse_symlink( + (struct reparse_symlink_data_buffer *)buf, + plen, target_path, cifs_sb); + default: + cifs_dbg(VFS, "srv returned unknown symlink buffer " + "tag:0x%08x\n", le32_to_cpu(buf->ReparseTag)); + return -EOPNOTSUPP; + } } #define SMB2_SYMLINK_STRUCT_SIZE \ @@ -2581,23 +2592,8 @@ smb2_query_symlink(const unsigned int xid, struct cifs_tcon *tcon, goto querty_exit; } - if (plen < 8) { - cifs_dbg(VFS, "reparse buffer is too small. Must be " - "at least 8 bytes but was %d\n", plen); - rc = -EIO; - goto querty_exit; - } - - if (plen < le16_to_cpu(reparse_buf->ReparseDataLength) + 8) { - cifs_dbg(VFS, "srv returned invalid reparse buf " - "length: %d\n", plen); - rc = -EIO; - goto querty_exit; - } - - rc = parse_reparse_point( - (struct reparse_symlink_data_buffer *)reparse_buf, - plen, target_path, cifs_sb); + rc = parse_reparse_point(reparse_buf, plen, target_path, + cifs_sb); goto querty_exit; }