From: Alan Modra <amodra@gmail.com>
To: binutils@sourceware.org
Subject: PR29925, Memory leak in find_abstract_instance
Date: Thu, 22 Dec 2022 07:58:16 +1030 [thread overview]
Message-ID: <Y6N6cNwCN8q5hhHc@squeak.grove.modra.org> (raw)
The testcase in the PR had a variable with both DW_AT_decl_file and
DW_AT_specification, where the DW_AT_specification also specified
DW_AT_decl_file. This leads to a memory leak as the file name is
malloced and duplicates are not expected.
I've also changed find_abstract_instance to not use a temp for "name",
because that can result in a change in behaviour from the usual last
of duplicate attributes wins.
PR 29925
* dwarf2.c (find_abstract_instance): Delete "name" variable.
Free *filename_ptr before assigning new file name.
(scan_unit_for_symbols): Similarly free func->file and
var->file before assigning.
diff --git a/bfd/dwarf2.c b/bfd/dwarf2.c
index 0cd8152ee6e..b608afbc0cf 100644
--- a/bfd/dwarf2.c
+++ b/bfd/dwarf2.c
@@ -3441,7 +3441,6 @@ find_abstract_instance (struct comp_unit *unit,
struct abbrev_info *abbrev;
uint64_t die_ref = attr_ptr->u.val;
struct attribute attr;
- const char *name = NULL;
if (recur_count == 100)
{
@@ -3602,9 +3601,9 @@ find_abstract_instance (struct comp_unit *unit,
case DW_AT_name:
/* Prefer DW_AT_MIPS_linkage_name or DW_AT_linkage_name
over DW_AT_name. */
- if (name == NULL && is_str_form (&attr))
+ if (*pname == NULL && is_str_form (&attr))
{
- name = attr.u.str;
+ *pname = attr.u.str;
if (mangle_style (unit->lang) == 0)
*is_linkage = true;
}
@@ -3612,7 +3611,7 @@ find_abstract_instance (struct comp_unit *unit,
case DW_AT_specification:
if (is_int_form (&attr)
&& !find_abstract_instance (unit, &attr, recur_count + 1,
- &name, is_linkage,
+ pname, is_linkage,
filename_ptr, linenumber_ptr))
return false;
break;
@@ -3622,7 +3621,7 @@ find_abstract_instance (struct comp_unit *unit,
non-string forms into these attributes. */
if (is_str_form (&attr))
{
- name = attr.u.str;
+ *pname = attr.u.str;
*is_linkage = true;
}
break;
@@ -3630,8 +3629,11 @@ find_abstract_instance (struct comp_unit *unit,
if (!comp_unit_maybe_decode_line_info (unit))
return false;
if (is_int_form (&attr))
- *filename_ptr = concat_filename (unit->line_table,
- attr.u.val);
+ {
+ free (*filename_ptr);
+ *filename_ptr = concat_filename (unit->line_table,
+ attr.u.val);
+ }
break;
case DW_AT_decl_line:
if (is_int_form (&attr))
@@ -3643,7 +3645,6 @@ find_abstract_instance (struct comp_unit *unit,
}
}
}
- *pname = name;
return true;
}
@@ -4139,8 +4140,11 @@ scan_unit_for_symbols (struct comp_unit *unit)
case DW_AT_decl_file:
if (is_int_form (&attr))
- func->file = concat_filename (unit->line_table,
- attr.u.val);
+ {
+ free (func->file);
+ func->file = concat_filename (unit->line_table,
+ attr.u.val);
+ }
break;
case DW_AT_decl_line:
@@ -4182,8 +4186,11 @@ scan_unit_for_symbols (struct comp_unit *unit)
case DW_AT_decl_file:
if (is_int_form (&attr))
- var->file = concat_filename (unit->line_table,
- attr.u.val);
+ {
+ free (var->file);
+ var->file = concat_filename (unit->line_table,
+ attr.u.val);
+ }
break;
case DW_AT_decl_line:
--
Alan Modra
Australia Development Lab, IBM
reply other threads:[~2022-12-21 21:28 UTC|newest]
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