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@ajeddeloh
Created April 3, 2018 23:59
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###
### Load debuging information about GNU GRUB 2 modules into GDB
### automatically. Needs readelf, Perl and gmodule.pl script
###
### $Id: .gdbinit,v 1.1 2006/05/14 11:38:08 lkundrak Exp $
### Lubomir Kundrak <lkudrak@skosi.org>
###
set architecture i386:x86-64
#set architecture i8086
# Add section numbers and addresses to .segments.tmp
define dump_module_sections
set $mod = $arg0
# FIXME: save logging status
set logging file .segments.tmp
set logging redirect on
set logging overwrite off
set logging on
printf "%s", $mod->name
set $segment = $mod->segment
while ($segment)
printf " %i 0x%x", $segment->section, $segment->addr
set $segment = $segment->next
end
printf "\n"
set logging off
# FIXME: restore logging status
end
document dump_module_sections
Gather information about module whose mod structure was
given for use with match_and_load_symbols
end
# Generate and execute GDB commands and delete temporary files
# afterwards
define match_and_load_symbols
shell perl gmodule.pl <.segments.tmp >.loadsym.gdb
source .loadsym.gdb
shell rm -f .segments.tmp .loadsym.gdb
end
document match_and_load_symbols
Launch script, that matches section names with information
generated by dump_module_sections and load debugging info
apropriately
end
###
define load_module
dump_module_sections $arg0
match_and_load_symbols
end
document load_module
Load debugging information for module given as argument.
end
define load_all_modules
set $this = grub_dl_head
while ($this != 0)
dump_module_sections $this->mod
set $this = $this->next
end
match_and_load_symbols
end
document load_all_modules
Load debugging information for all loaded modules.
end
###
# really primitive stack trace
define rbp_walk
info sym $rip
set $frameptr = $rbp
while ($frameptr != 0)
set $oldbp = *((int*)($frameptr + 4))
info sym $oldbp
set $frameptr = *((int*)($frameptr))
end
end
file kernel.exec
target remote :1234
# this address is the "free magic broken" address for 1618.0.0
watch *0x3cec8166
# inform when module is loaded
break grub_dl_add
commands
silent
load_module mod
cont
end
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