-
Helge Deller authored
As on x86-64 and other architectures, the boot kernel on parisc (vmlinuz and bzImage) contains a full compressed copy of the final kernel executable (vmlinux.bin.gz), which one should be able to extract with the extract-vmlinux script. But on parisc extracting the kernel with extract-vmlinux fails. Currently the script first checks if the given file is an ELF file (which is true on parisc) and if so returns it. Thus on parisc we unexpectedly get back the vmlinuz boot file instead of the uncompressed vmlinux image. This patch fixes this issue by reverting the logic. It now first tries to find a compression signature in the given file and if that fails it checks the file itself as fallback. Signed-off-by:
Helge Deller <deller@gmx.de>
Helge Deller authoredAs on x86-64 and other architectures, the boot kernel on parisc (vmlinuz and bzImage) contains a full compressed copy of the final kernel executable (vmlinux.bin.gz), which one should be able to extract with the extract-vmlinux script. But on parisc extracting the kernel with extract-vmlinux fails. Currently the script first checks if the given file is an ELF file (which is true on parisc) and if so returns it. Thus on parisc we unexpectedly get back the vmlinuz boot file instead of the uncompressed vmlinux image. This patch fixes this issue by reverting the logic. It now first tries to find a compression signature in the given file and if that fails it checks the file itself as fallback. Signed-off-by:
Helge Deller <deller@gmx.de>
Code owners
Assign users and groups as approvers for specific file changes. Learn more.
extract-vmlinux 1.68 KiB
#!/bin/sh
# ----------------------------------------------------------------------
# extract-vmlinux - Extract uncompressed vmlinux from a kernel image
#
# Inspired from extract-ikconfig
# (c) 2009,2010 Dick Streefland <dick@streefland.net>
#
# (c) 2011 Corentin Chary <corentin.chary@gmail.com>
#
# Licensed under the GNU General Public License, version 2 (GPLv2).
# ----------------------------------------------------------------------
check_vmlinux()
{
# Use readelf to check if it's a valid ELF
# TODO: find a better to way to check that it's really vmlinux
# and not just an elf
readelf -h $1 > /dev/null 2>&1 || return 1
cat $1
exit 0
}
try_decompress()
{
# The obscure use of the "tr" filter is to work around older versions of
# "grep" that report the byte offset of the line instead of the pattern.
# Try to find the header ($1) and decompress from here
for pos in `tr "$1\n$2" "\n$2=" < "$img" | grep -abo "^$2"`
do
pos=${pos%%:*}
tail -c+$pos "$img" | $3 > $tmp 2> /dev/null
check_vmlinux $tmp
done
}
# Check invocation:
me=${0##*/}
img=$1
if [ $# -ne 1 -o ! -s "$img" ]
then
echo "Usage: $me <kernel-image>" >&2
exit 2
fi
# Prepare temp files:
tmp=$(mktemp /tmp/vmlinux-XXX)
trap "rm -f $tmp" 0
# That didn't work, so retry after decompression.
try_decompress '\037\213\010' xy gunzip
try_decompress '\3757zXZ\000' abcde unxz
try_decompress 'BZh' xy bunzip2
try_decompress '\135\0\0\0' xxx unlzma
try_decompress '\211\114\132' xy 'lzop -d'
try_decompress '\002!L\030' xxx 'lz4 -d'
try_decompress '(\265/\375' xxx unzstd
# Finally check for uncompressed images or objects:
check_vmlinux $img
# Bail out:
echo "$me: Cannot find vmlinux." >&2