OpenE2K
/
binutils-gdb
12
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Don't crash if dwarf_decode_macro_bytes's 'body' is NULL 

Hi,

Ref.: https://bugzilla.redhat.com/show_bug.cgi?id=1708192
      https://bugzilla.redhat.com/show_bug.cgi?id=1708786

During the Fedora RPM build process, gdb-add-index is invoked to
extract the DWARF index from the binary, and GDB will segfault because
dwarf2read.c:parse_definition_macro's 'body' variable is NULL.

The underlying problem is that Fedora's rpm-build's "debugedit"
program will silently corrupt .debug_macro strings when a binary is
compiled with -g3.  This is being taken care of by Mark Wielaard,
here:

  https://bugzilla.redhat.com/show_bug.cgi?id=1708786

However, I still feel it's important to make GDB more resilient
against invalid DWARF input, so I'm proposing this rather simple patch
to catch the situation when "body == NULL" (i.e., it's probably been
corrupted) and issue a complaint.  This is not a real fix to the
problem, of course, but at least GDB is able to finish without
segfaulting.

OK for master?

gdb/ChangeLog:
2019-05-15  Sergio Durigan Junior  <sergiodj@redhat.com>

	Ref.: https://bugzilla.redhat.com/show_bug.cgi?id=1708192
	* dwarf2read.c (dwarf_decode_macro_bytes): Check whether 'body' is
	NULL, and complain if that's the case.
This commit is contained in:
Sergio Durigan Junior 2019-05-10 16:57:26 -04:00
parent 905f5b3f1d
commit 7bede82892
2 changed files with 24 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
gdb/ChangeLog
View File

@ -1,3 +1,9 @@
2019-05-15 Sergio Durigan Junior <sergiodj@redhat.com>
Ref.: https://bugzilla.redhat.com/show_bug.cgi?id=1708192
* dwarf2read.c (parse_macro_definition): Check whether 'body' is
NULL, and complain/return if that's the case.
2019-05-15 John Darrington <john@darrington.wattle.id.au>
* s12z-tdep.c (push_pull_get_stack_adjustment): New function.

19
gdb/dwarf2read.c
View File

@ -24609,7 +24609,24 @@ dwarf_decode_macro_bytes (struct dwarf2_cu *cu,
line == 0 ? _("zero") : _("non-zero"), line, body);
if (is_define)
parse_macro_definition (current_file, line, body);
{
if (body != NULL)
parse_macro_definition (current_file, line, body);
else
{
/* Fedora's rpm-build's "debugedit" binary
corrupted .debug_macro sections.
For more info, see
https://bugzilla.redhat.com/show_bug.cgi?id=1708786 */
complaint (_("debug info gives %s invalid macro definition "
"without body (corrupted?) at line %d"
"on file %s"),
at_commandline ? _("command-line")
: _("in-file"),
line, current_file->filename);
}
}
else
{
gdb_assert (macinfo_type == DW_MACRO_undef