Fix checksum writing in signboot.sh

The printf command takes an octal value after \, so we have to convert
our decimal representation to octal first and then write it.

This unbreaks extboot signing. Multiboot wasn't affected yet because
the checksum was < 8.

Spotted and first patch by Glauber Costa <glommer@redhat.com>.
Printf idea by Paolo Bonzini <bonzini@gnu.org>.

Signed-off-by: Alexander Graf <agraf@suse.de>
CC: Glauber Costa <glommer@redhat.com>
CC: Paolo Bonzini <bonzini@gnu.org>
CC: Jan Ondrej <ondrejj@salstar.sk>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Message-Id:

diff --git a/pc-bios/optionrom/signrom.sh b/pc-bios/optionrom/signrom.sh
index 43228113726d425f6c3a07306b286f380f12321b..975b27dd602150f64cf4fe213225f5cf2f66f77a 100755 (executable)
--- a/pc-bios/optionrom/signrom.sh
+++ b/pc-bios/optionrom/signrom.sh
@@ -39,7 +39,8 @@ done
 
 sum=$(( $sum % 256 ))
 sum=$(( 256 - $sum ))
+sum_octal=$( printf "%o" $sum )
 
 # and write the output file
 cp "$1" "$2"
-printf "\\$sum" | dd of="$2" bs=1 count=1 seek=$size conv=notrunc 2>/dev/null
+printf "\\$sum_octal" | dd of="$2" bs=1 count=1 seek=$size conv=notrunc 2>/dev/null