Daniel Fandrich wrote: > parted 3.0 crashes for me when accessing the attached EFI partition table > with the following crash log. This was compiled on an ubuntu 11.04 x86_64 > Linux system. ... > Assertion (last_usable <= disk->dev->length) at gpt.c:727 in function > _parse_header() failed.
Thank you for the complete bug report. Here's the patch I'm about to push: >From bd21f396933c6fc8c8877eba4855c96569710392 Mon Sep 17 00:00:00 2001 From: Jim Meyering <meyer...@redhat.com> Date: Fri, 24 Jun 2011 13:32:33 +0200 Subject: [PATCH] gpt: don't abort for a truncated GPT-formatted device This fixes the problem two ways. The first fix (via gpt_alloc) rejects any device that is too small, but it is insufficient. Choose a slightly larger truncated device with an otherwise intact primary GPT header and you can still trigger the failed assertion. To fix it in general, we make _header_is_valid detect the problem. * libparted/labels/gpt.c (gpt_alloc): Reject a device that is so small that there is no room for a single partition. (_header_is_valid): Validate LastUsableLBA here, as well, so that we now reject as invalid any GPT header that specifies a LastUsableLBA larger than the device size. Leave the assertion in _parse_header. * tests/t0203-gpt-tiny-device-abort.sh: Test for this. * tests/Makefile.am (TESTS): Add it. * NEWS: (Bug fixes): Mention it. Reported by Daniel Fandrich in http://thread.gmane.org/gmane.comp.gnu.parted.bugs/10466 --- NEWS | 2 + libparted/labels/gpt.c | 16 ++++++++++-- tests/Makefile.am | 1 + tests/t0203-gpt-tiny-device-abort.sh | 44 ++++++++++++++++++++++++++++++++++ 4 files changed, 60 insertions(+), 3 deletions(-) create mode 100644 tests/t0203-gpt-tiny-device-abort.sh diff --git a/NEWS b/NEWS index 790b303..ae4dc37 100644 --- a/NEWS +++ b/NEWS @@ -4,6 +4,8 @@ GNU parted NEWS -*- outline -*- ** Bug fixes + libparted: no longer aborts for a pathologically small GPT-formatted device + libparted: works with a two-component linux kernel version number like 3.0 diff --git a/libparted/labels/gpt.c b/libparted/labels/gpt.c index e1c0a32..8c9816f 100644 --- a/libparted/labels/gpt.c +++ b/libparted/labels/gpt.c @@ -517,13 +517,19 @@ gpt_alloc (const PedDevice *dev) disk = _ped_disk_alloc ((PedDevice *) dev, &gpt_disk_type); if (!disk) goto error; - disk->disk_specific = gpt_disk_data = ped_malloc (sizeof (GPTDiskData)); - if (!disk->disk_specific) - goto error_free_disk; data_start = 2 + GPT_DEFAULT_PARTITION_ENTRY_ARRAY_SIZE / dev->sector_size; data_end = dev->length - 2 - GPT_DEFAULT_PARTITION_ENTRY_ARRAY_SIZE / dev->sector_size; + + /* If the device is too small to have room for data, reject it. */ + if (data_end <= data_start) + goto error_free_disk; + + disk->disk_specific = gpt_disk_data = ped_malloc (sizeof (GPTDiskData)); + if (!disk->disk_specific) + goto error_free_disk; + ped_geometry_init (&gpt_disk_data->data_area, dev, data_start, data_end - data_start + 1); gpt_disk_data->entry_count = GPT_DEFAULT_PARTITION_ENTRIES; @@ -665,6 +671,10 @@ _header_is_valid (PedDisk const *disk, GuidPartitionTableHeader_t *gpt, if (first_usable < 3) return 0; + PedSector last_usable = PED_LE64_TO_CPU (gpt->LastUsableLBA); + if (disk->dev->length < last_usable) + return 0; + origcrc = gpt->HeaderCRC32; gpt->HeaderCRC32 = 0; if (pth_crc32 (dev, gpt, &crc) != 0) diff --git a/tests/Makefile.am b/tests/Makefile.am index b57142b..86402c0 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -11,6 +11,7 @@ TESTS = \ t0200-gpt.sh \ t0201-gpt.sh \ t0202-gpt-pmbr.sh \ + t0203-gpt-tiny-device-abort.sh \ t0205-gpt-list-clobbers-pmbr.sh \ t0206-gpt-print-with-corrupt-primary-clobbers-pmbr.sh \ t0207-IEC-binary-notation.sh \ diff --git a/tests/t0203-gpt-tiny-device-abort.sh b/tests/t0203-gpt-tiny-device-abort.sh new file mode 100644 index 0000000..22c8b21 --- /dev/null +++ b/tests/t0203-gpt-tiny-device-abort.sh @@ -0,0 +1,44 @@ +#!/bin/sh +# parted before 3.1 could abort for a pathologically small device with +# a valid primary GPT header but no room for the backup header. + +# Copyright (C) 2009-2011 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/>. + +. "${srcdir=.}/init.sh"; path_prepend_ ../parted + +N=2M +dev=loop-file +# create a file large enough to hold a GPT partition table +dd if=/dev/null of=$dev bs=1 seek=$N || framework_failure + +# create a GPT partition table +parted -s $dev mklabel gpt > out 2>&1 || fail=1 +# expect no output +compare out /dev/null || fail=1 + +# truncate it to 34 sectors. +for i in 33 34 35 67 68 69 101 102 103; do + dd if=$dev of=bad count=$i + + # Print the partition table. Before, this would evoke a failed assertion. + printf 'i\no\n' > in + parted ---pretend-input-tty bad u s p < in > out 2> err || fail=1 + # don't bother comparing stdout + # expect no stderr + compare err /dev/null || fail=1 +done + +Exit $fail -- 1.7.6.rc2.302.gc2115 _______________________________________________ bug-parted mailing list bug-parted@gnu.org https://lists.gnu.org/mailman/listinfo/bug-parted