From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 20732 invoked by alias); 21 Apr 2011 13:13:42 -0000 Received: (qmail 20710 invoked by uid 9737); 21 Apr 2011 13:13:42 -0000 Date: Thu, 21 Apr 2011 13:13:00 -0000 Message-ID: <20110421131342.20708.qmail@sourceware.org> From: zkabelac@sourceware.org To: lvm-devel@redhat.com, lvm2-cvs@sourceware.org Subject: LVM2 ./WHATS_NEW lib/format_text/format-text.c ... Mailing-List: contact lvm2-cvs-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: lvm2-cvs-owner@sourceware.org X-SW-Source: 2011-04/txt/msg00021.txt.bz2 CVSROOT: /cvs/lvm2 Module name: LVM2 Changes by: zkabelac@sourceware.org 2011-04-21 13:13:41 Modified files: . : WHATS_NEW lib/format_text: format-text.c lib/metadata : metadata.c Added files: test : t-pv-duplicate.sh Log message: Fix use of released vgname and vgid Avoid using of already released memory when duplicated MDA is found. As get_pv_from_vg_by_id() may call lvmcache_label_scan() use the local copy of the vgname and vgid on the stack as vginfo may dissapear and code was then accessing garbage in memory. i.e. pvs /dev/loop0 (when /dev/loop0 and /dev/loop1 has same MDA content) Invalid read of size 1 at 0x523C986: dm_hash_lookup (hash.c:325) by 0x440C8C: vginfo_from_vgname (lvmcache.c:399) by 0x4605C0: _create_vg_text_instance (format-text.c:1882) by 0x46140D: _text_create_text_instance (format-text.c:2243) by 0x47EB49: _vg_read (metadata.c:2887) by 0x47FBD8: vg_read_internal (metadata.c:3231) by 0x477594: get_pv_from_vg_by_id (metadata.c:344) by 0x45F07A: _get_pv_if_in_vg (format-text.c:1400) by 0x45F0B9: _populate_pv_fields (format-text.c:1414) by 0x45F40F: _text_pv_read (format-text.c:1493) by 0x480431: _pv_read (metadata.c:3500) by 0x4802B2: pv_read (metadata.c:3462) Address 0x652ab80 is 0 bytes inside a block of size 4 free'd at 0x4C2756E: free (vg_replace_malloc.c:366) by 0x442277: _free_vginfo (lvmcache.c:963) by 0x44235E: _drop_vginfo (lvmcache.c:992) by 0x442B23: _lvmcache_update_vgname (lvmcache.c:1165) by 0x443449: lvmcache_update_vgname_and_id (lvmcache.c:1358) by 0x443C07: lvmcache_add (lvmcache.c:1492) by 0x46588C: _text_read (text_label.c:271) by 0x466A65: label_read (label.c:289) by 0x4413FC: lvmcache_label_scan (lvmcache.c:635) by 0x4605AD: _create_vg_text_instance (format-text.c:1881) by 0x46140D: _text_create_text_instance (format-text.c:2243) by 0x47EB49: _vg_read (metadata.c:2887) Add testing script Patches: http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/WHATS_NEW.diff?cvsroot=lvm2&r1=1.1972&r2=1.1973 http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/lib/format_text/format-text.c.diff?cvsroot=lvm2&r1=1.178&r2=1.179 http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/lib/metadata/metadata.c.diff?cvsroot=lvm2&r1=1.454&r2=1.455 http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/test/t-pv-duplicate.sh.diff?cvsroot=lvm2&r1=NONE&r2=1.1 --- LVM2/WHATS_NEW 2011/04/13 18:26:39 1.1972 +++ LVM2/WHATS_NEW 2011/04/21 13:13:40 1.1973 @@ -1,5 +1,6 @@ Version 2.02.85 - =================================== + Fix use of released memory when duplicate PV is found. Add "devices/issue_discards" to lvm.conf. Issue discards on lvremove, lvreduce, etc if enabled and supported. Fix incorrect tests for dm_snprintf() failure. --- LVM2/lib/format_text/format-text.c 2011/03/11 15:10:17 1.178 +++ LVM2/lib/format_text/format-text.c 2011/04/21 13:13:40 1.179 @@ -1395,11 +1395,23 @@ static int _get_pv_if_in_vg(struct lvmcache_info *info, struct physical_volume *pv) { + char vgname[NAME_LEN + 1]; + char vgid[ID_LEN + 1]; + if (info->vginfo && info->vginfo->vgname && - !is_orphan_vg(info->vginfo->vgname) && - get_pv_from_vg_by_id(info->fmt, info->vginfo->vgname, - info->vginfo->vgid, info->dev->pvid, pv)) - return 1; + !is_orphan_vg(info->vginfo->vgname)) { + /* + * get_pv_from_vg_by_id() may call + * lvmcache_label_scan() and drop cached + * vginfo so make a local copy of string. + */ + strcpy(vgname, info->vginfo->vgname); + memcpy(vgid, info->vginfo->vgid, sizeof(vgid)); + + if (get_pv_from_vg_by_id(info->fmt, vgname, vgid, + info->dev->pvid, pv)) + return 1; + } return 0; } --- LVM2/lib/metadata/metadata.c 2011/04/08 14:40:20 1.454 +++ LVM2/lib/metadata/metadata.c 2011/04/21 13:13:40 1.455 @@ -2771,6 +2771,9 @@ * If precommitted is set, use precommitted metadata if present. * * Either of vgname or vgid may be NULL. + * + * Note: vginfo structs must not be held or used as parameters + * across the call to this function. */ static struct volume_group *_vg_read(struct cmd_context *cmd, const char *vgname, /cvs/lvm2/LVM2/test/t-pv-duplicate.sh,v --> standard output revision 1.1 --- LVM2/test/t-pv-duplicate.sh +++ - 2011-04-21 13:13:42.016714000 +0000 @@ -0,0 +1,25 @@ +#!/bin/sh +# Copyright (C) 2011 Red Hat, Inc. All rights reserved. +# +# This copyrighted material is made available to anyone wishing to use, +# modify, copy, or redistribute it subject to the terms and conditions +# of the GNU General Public License v.2. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software Foundation, +# Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + +# 'Exercise duplicate metadata diagnostics' + +. lib/test + +aux prepare_devs 3 + +vgcreate -c n --metadatasize 128k $vg1 $dev1 + +# copy mda +dd if=$dev1 of=$dev2 bs=256K count=1 +dd if=$dev1 of=$dev3 bs=256K count=1 + +pvs $dev1 +vgs $vg1