On 03/07/2018 05:25 PM, Mark Wielaard wrote:
debugedit would blindly use an .debug_str index from the .debug_info or
.debug_line sections assuming it would result in a valid string. Which
would crash and burn if the DWARF data was bogus when the string was
used. So check whenever converting an string index into a char pointer
so we can produce a more helpful error message.
https://bugzilla.redhat.com/show_bug.cgi?id=1543912
Signed-off-by: Mark Wielaard <m...@klomp.org>
---
tools/debugedit.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/tools/debugedit.c b/tools/debugedit.c
index 57cd830..6c71cbc 100644
--- a/tools/debugedit.c
+++ b/tools/debugedit.c
@@ -820,6 +820,9 @@ record_file_string_entry_idx (struct strings *strings,
size_t old_idx)
struct stridxentry *entry = string_find_new_entry (strings, old_idx);
if (entry != NULL)
{
+ if (old_idx >= debug_sections[DEBUG_STR].size)
+ error (1, 0, "Bad string pointer index %zd", old_idx);
+
Strent *strent;
const char *old_str = (char *)debug_sections[DEBUG_STR].data + old_idx;
const char *file = skip_dir_prefix (old_str, base_dir);
@@ -870,6 +873,9 @@ record_existing_string_entry_idx (struct strings *strings,
size_t old_idx)
struct stridxentry *entry = string_find_new_entry (strings, old_idx);
if (entry != NULL)
{
+ if (old_idx >= debug_sections[DEBUG_STR].size)
+ error (1, 0, "Bad string pointer index %zd", old_idx);
+
const char *str = (char *)debug_sections[DEBUG_STR].data + old_idx;
Strent *strent = strtab_add_len (strings->str_tab,
str, strlen (str) + 1);
@@ -1533,6 +1539,10 @@ edit_attributes (DSO *dso, unsigned char *ptr, struct
abbrev_tag *t, int phase)
{
const char *dir;
size_t idx = do_read_32_relocated (ptr);
+ if (idx >= debug_sections[DEBUG_STR].size)
+ error (1, 0,
+ "%s: Bad string pointer index %zd for comp_dir",
+ dso->filename, idx);
dir = (char *) debug_sections[DEBUG_STR].data + idx;
free (comp_dir);
@@ -1558,6 +1568,10 @@ edit_attributes (DSO *dso, unsigned char *ptr, struct
abbrev_tag *t, int phase)
case. */
char *name;
size_t idx = do_read_32_relocated (ptr);
+ if (idx >= debug_sections[DEBUG_STR].size)
+ error (1, 0,
+ "%s: Bad string pointer index %zd for unit name",
+ dso->filename, idx);
name = (char *) debug_sections[DEBUG_STR].data + idx;
if (*name == '/' && comp_dir == NULL)
{
I was somewhat tempted to mumble something about putting these
common-looking checks into a function but ... meh, it's Friday :P
Applied, thanks for the patch!
- Panu -
_______________________________________________
Rpm-maint mailing list
Rpm-maint@lists.rpm.org
http://lists.rpm.org/mailman/listinfo/rpm-maint
