Petr Uzel <[email protected]> wrote: > Here is a simple shell script that illustrates the incorrect behavior. > The patch I've sent before fixes the issue (at least for me ;) ). > > ============================ > I'd like to transform it to the form of parted-testsuite, but it will > take me some time as I'm not familiar much with it - any hints would > be highly appreciated ;)
Great. Thanks for the example. Here's how I'd do it, using only a backing file. No need for lvm. First I do it at the shell/command-line level: dev=file dd if=/dev/null of=$dev bs=1 seek=30M ./parted -s $dev mklabel gpt dd if=$dev of=before bs=512 count=1 skip=1 2>/dev/null ./parted -m -s $dev p # make the backing file larger. one byte is enough printf x >> $dev ./parted -m -s $dev p Error: The backup GPT table is not at the end of the disk, as it should be... ... dd if=$dev of=after bs=512 count=1 skip=1 2>/dev/null cmp before after before after differ: byte 17, line 1 [Exit 1] Then I made that into a test like any of the others: [I chose a low numbered name for the new file, because this is a very fundamental property of partition tables (no file system aspects involved) ] In the process, I discovered a GPT-related bug that would provoke a failed assertion. So I fixed that. Patch below. Would you like to write the test case for *it*? If so, please name it t0201-gpt.sh, since it'll be very similar to the one below (which has a FIXME comment I plan to address before pushing). My plan for tomorrow: - apply your patch, and test a little - address FIXME comment in the test script below - ensure that the test passes - push your patch and the test-adding one If you write the test to exercise my patch, (or tell me you'd rather not, in which case I'll do it), I'll push those two change sets, too. >From efeaceacd3af6a8b1b7dcc006e87f99daf15f997 Mon Sep 17 00:00:00 2001 From: Jim Meyering <[email protected]> Date: Mon, 16 Feb 2009 17:54:57 +0100 Subject: [PATCH 1/2] gpt: add a test: printing a partition table must not modify it * tests/t0200-gpt.sh: New file. * tests/Makefile.am (TESTS): Add the new test. --- tests/Makefile.am | 1 + tests/t0200-gpt.sh | 55 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 56 insertions(+), 0 deletions(-) create mode 100755 tests/t0200-gpt.sh diff --git a/tests/Makefile.am b/tests/Makefile.am index 1214f9c..14e4862 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -1,6 +1,7 @@ TESTS = \ t0000-basic.sh \ t0100-print.sh \ + t0200-gpt.sh \ t1000-mkpartfs.sh \ t1100-busy-label.sh \ t1500-small-ext2.sh \ diff --git a/tests/t0200-gpt.sh b/tests/t0200-gpt.sh new file mode 100755 index 0000000..013b0a4 --- /dev/null +++ b/tests/t0200-gpt.sh @@ -0,0 +1,55 @@ +#!/bin/sh + +# Copyright (C) 2009 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. + +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +test_description='ensure that printing a partition table does not modify it' + +: ${srcdir=.} +. $srcdir/test-lib.sh + +N=2M +dev=loop-file +test_expect_success \ + 'create a file large enough to hold a gpt partition table' \ + "dd if=/dev/null of=$dev bs=1 seek=$N 2> /dev/null" + +test_expect_success \ + 'create a gpt partition table' \ + 'parted -s $dev mklabel gpt > out 2>&1' +test_expect_success 'expect no output' '$compare out /dev/null' + +test_expect_success \ + 'save a copy of the original primary GPT table' \ + 'dd if=$dev of=before count=1 skip=1' + +test_expect_success \ + 'extend the backing file by 1 byte' \ + 'printf x >> $dev' + +test_expect_success \ + 'use parted simply to print the partition table' \ + 'parted -m -s $dev p > out 2> err' +# FIXME compare expected out and err + +test_expect_success \ + 'extract the primary GPT table again' \ + 'dd if=$dev of=after count=1 skip=1' + +test_expect_success \ + 'compare partition tables (they had better be identical)' \ + 'compare before after' + +test_done -- 1.6.2.rc0.264.g60787 >From 3dd5698e74dcff6b6a6af0f53a02ec880e64701b Mon Sep 17 00:00:00 2001 From: Jim Meyering <[email protected]> Date: Mon, 16 Feb 2009 19:02:58 +0100 Subject: [PATCH 2/2] avoid failed assertion when creating a GPT partition table... on top of an old one for a larger device Here's the reproducer: dev=file dd if=/dev/null of=$dev bs=1 seek=30M ./parted -s $dev mklabel gpt dd if=$dev of=prim_gpt_before bs=512 count=1 skip=1 2>/dev/null ./parted -m -s $dev p truncate -s +10M $dev ./parted -m -s $dev p dd if=/dev/null of=$dev bs=1 seek=30M ./parted -s $dev mklabel gpt --- libparted/labels/gpt.c | 11 ++++++++--- 1 files changed, 8 insertions(+), 3 deletions(-) diff --git a/libparted/labels/gpt.c b/libparted/labels/gpt.c index 13d2e88..62beead 100644 --- a/libparted/labels/gpt.c +++ b/libparted/labels/gpt.c @@ -4,7 +4,7 @@ original version by Matt Domsch <[email protected]> Disclaimed into the Public Domain - Portions Copyright (C) 2001-2003, 2005-2008 Free Software Foundation, Inc. + Portions Copyright (C) 2001-2003, 2005-2009 Free Software Foundation, Inc. EFI GUID Partition Table handling Per Intel EFI Specification v1.02 @@ -824,8 +824,13 @@ gpt_read (PedDisk * disk) goto error; if (_read_header (disk->dev, &gpt, 1)) { - PED_ASSERT ((PedSector) PED_LE64_TO_CPU (gpt->AlternateLBA) - <= disk->dev->length - 1, goto error_free_gpt); + /* There used to be a GPT partition table here, with an + alternate LBA that extended beyond the current + end-of-device. Treat it as a non-match. */ + if ((PedSector) PED_LE64_TO_CPU (gpt->AlternateLBA) + > disk->dev->length - 1) + goto error_free_gpt; + if ((PedSector) PED_LE64_TO_CPU (gpt->AlternateLBA) < disk->dev->length - 1) { char* zeros = ped_malloc (pth_get_size (disk->dev)); -- 1.6.2.rc0.264.g60787 _______________________________________________ parted-devel mailing list [email protected] http://lists.alioth.debian.org/mailman/listinfo/parted-devel
