From: Alan Modra <amodra@gmail.com>
To: binutils@sourceware.org
Subject: bfd_get_symbol_leading_char vs. ""
Date: Wed, 23 Aug 2023 11:07:20 +0930 [thread overview]
Message-ID: <ZOVi0Fjw5fb6SH7S@squeak.grove.modra.org> (raw)
Some places matching the first char of a string against
bfd_get_symbol_leading_char, which may be zero, didn't check for the
string being "". This patch adds the check to stop accesses past the
end of the string and potential buffer overruns.
The dlltool one was found by oss-fuzz quite a while ago.
bfd/
* cofflink.c (_bfd_coff_link_input_bfd): Ensure a zero
bfd_get_symbol_leading_char doesn't lead to accessing past the
zero string terminator.
* linker.c (bfd_wrapped_link_hash_lookup): Likewise.
(unwrap_hash_lookup): Likewise.
binutils/
* dlltool.c (scan_filtered_symbols): Ensure a zero
bfd_get_symbol_leading_char doesn't lead to accessing past the
zero string terminator.
diff --git a/bfd/cofflink.c b/bfd/cofflink.c
index aea5c4c38a5..221f6e8183a 100644
--- a/bfd/cofflink.c
+++ b/bfd/cofflink.c
@@ -1618,7 +1618,8 @@ _bfd_coff_link_input_bfd (struct coff_final_link_info *flaginfo, bfd *input_bfd)
/* Ignore fake names invented by compiler; treat them all as
the same name. */
if (*name == '~' || *name == '.' || *name == '$'
- || (*name == bfd_get_symbol_leading_char (input_bfd)
+ || (*name
+ && *name == bfd_get_symbol_leading_char (input_bfd)
&& (name[1] == '~' || name[1] == '.' || name[1] == '$')))
name = "";
diff --git a/bfd/linker.c b/bfd/linker.c
index 0f4f9a1776c..28fffc3ad63 100644
--- a/bfd/linker.c
+++ b/bfd/linker.c
@@ -544,7 +544,9 @@ bfd_wrapped_link_hash_lookup (bfd *abfd,
char prefix = '\0';
l = string;
- if (*l == bfd_get_symbol_leading_char (abfd) || *l == info->wrap_char)
+ if (*l
+ && (*l == bfd_get_symbol_leading_char (abfd)
+ || *l == info->wrap_char))
{
prefix = *l;
++l;
@@ -621,8 +623,9 @@ unwrap_hash_lookup (struct bfd_link_info *info,
{
const char *l = h->root.string;
- if (*l == bfd_get_symbol_leading_char (input_bfd)
- || *l == info->wrap_char)
+ if (*l
+ && (*l == bfd_get_symbol_leading_char (input_bfd)
+ || *l == info->wrap_char))
++l;
if (startswith (l, WRAP))
diff --git a/binutils/dlltool.c b/binutils/dlltool.c
index 085d4c2ce41..6d63e11e084 100644
--- a/binutils/dlltool.c
+++ b/binutils/dlltool.c
@@ -1500,7 +1500,8 @@ scan_filtered_symbols (bfd *abfd, void *minisyms, long symcount,
bfd_fatal (bfd_get_filename (abfd));
symbol_name = bfd_asymbol_name (sym);
- if (bfd_get_symbol_leading_char (abfd) == symbol_name[0])
+ if (*symbol_name
+ && *symbol_name == bfd_get_symbol_leading_char (abfd))
++symbol_name;
def_exports (xstrdup (symbol_name) , 0, -1, 0, 0,
--
Alan Modra
Australia Development Lab, IBM
reply other threads:[~2023-08-23 1:37 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=ZOVi0Fjw5fb6SH7S@squeak.grove.modra.org \
--to=amodra@gmail.com \
--cc=binutils@sourceware.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).