From 5f8987d3999edb26e757115fe87be55787d510b9 Mon Sep 17 00:00:00 2001
From: Nick Clifton <nickc@redhat.com>
Date: Tue, 17 Dec 2024 09:18:57 +0000
Subject: [PATCH] nm: Avoid potential segmentation fault when displaying
symbols without version info.
PR 32467
---
binutils/nm.c | 24 ++++++++++++++++--------
1 file changed, 16 insertions(+), 8 deletions(-)
diff --git a/binutils/nm.c b/binutils/nm.c
index faf27c59b4d..0ba7604d34f 100644
--- a/binutils/nm.c
+++ b/binutils/nm.c
@@ -682,7 +682,7 @@ print_symname (const char *form, struct extended_symbol_info *info,
const char *name, bfd *abfd)
{
char *alloc = NULL;
- char *atver = NULL;
+ char *atname = NULL;
if (name == NULL)
name = info->sinfo->name;
@@ -690,9 +690,19 @@ print_symname (const char *form, struct extended_symbol_info *info,
if (!with_symbol_versions
&& bfd_get_flavour (abfd) == bfd_target_elf_flavour)
{
- atver = strchr (name, '@');
+ char *atver = strchr (name, '@');
+
if (atver)
- *atver = 0;
+ {
+ /* PR 32467 - Corrupt binaries might include an @ character in a
+ symbol name. Since non-versioned symbol names can be in
+ read-only memory (via memory mapping of a file's contents) we
+ cannot just replace the @ character with a NUL. Instead we
+ create a truncated copy of the name. */
+ atname = xstrdup (name);
+ atname [atver - name] = 0;
+ name = atname;
+ }
}
if (do_demangle && *name)
@@ -703,9 +713,7 @@ print_symname (const char *form, struct extended_symbol_info *info,
}
if (unicode_display != unicode_default)
- {
- name = convert_utf8 (name);
- }
+ name = convert_utf8 (name);
if (info != NULL && info->elfinfo && with_symbol_versions)
{
@@ -726,8 +734,8 @@ print_symname (const char *form, struct extended_symbol_info *info,
}
}
printf (form, name);
- if (atver)
- *atver = '@';
+
+ free (atname);
free (alloc);
}
--
2.43.5