public inbox for binutils@sourceware.org
 help / color / mirror / Atom feed
From: Alan Modra <amodra@gmail.com>
To: binutils@sourceware.org
Subject: Sanity check reloc count in get_reloc_upper_bound
Date: Thu, 10 Nov 2022 20:41:55 +1030	[thread overview]
Message-ID: <Y2zOaxv1jkhwTIAi@squeak.grove.modra.org> (raw)

The idea here is the stop tools from allocating up to 32G per section
for the arelent pointer array, only to find a little later that the
section reloc count was fuzzed.  This usually doesn't hurt much (on
systems that allow malloc overcommit) except when compiled with asan.

We already do this for ELF targets, and while fixing the logic
recently I decided other targets ought to do the same.

	* elf64-sparc.c (elf64_sparc_get_reloc_upper_bound): Sanity check
	section reloc count against file size.
	* mach-o.c (bfd_mach_o_get_reloc_upper_bound): Likewise.
	* aoutx.h (get_reloc_upper_bound): Likewise, and don't duplicate
	check done in bfd_get_reloc_upper_bound.
	* pdp11.c (get_reloc_upper_bound): Likewise.
	* coffgen.c (coff_get_reloc_upper_bound): Likewise.

diff --git a/bfd/aoutx.h b/bfd/aoutx.h
index 4aed23426ca..61ea9f7ce04 100644
--- a/bfd/aoutx.h
+++ b/bfd/aoutx.h
@@ -2485,13 +2485,7 @@ NAME (aout, canonicalize_reloc) (bfd *abfd,
 long
 NAME (aout, get_reloc_upper_bound) (bfd *abfd, sec_ptr asect)
 {
-  bfd_size_type count;
-
-  if (bfd_get_format (abfd) != bfd_object)
-    {
-      bfd_set_error (bfd_error_invalid_operation);
-      return -1;
-    }
+  size_t count, raw;
 
   if (asect->flags & SEC_CONSTRUCTOR)
     count = asect->reloc_count;
@@ -2507,11 +2501,21 @@ NAME (aout, get_reloc_upper_bound) (bfd *abfd, sec_ptr asect)
       return -1;
     }
 
-  if (count >= LONG_MAX / sizeof (arelent *))
+  if (count >= LONG_MAX / sizeof (arelent *)
+      || _bfd_mul_overflow (count, obj_reloc_entry_size (abfd), &raw))
     {
       bfd_set_error (bfd_error_file_too_big);
       return -1;
     }
+  if (!bfd_write_p (abfd))
+    {
+      ufile_ptr filesize = bfd_get_file_size (abfd);
+      if (filesize != 0 && raw > filesize)
+	{
+	  bfd_set_error (bfd_error_file_truncated);
+	  return -1;
+	}
+    }
   return (count + 1) * sizeof (arelent *);
 }
 \f
diff --git a/bfd/coffgen.c b/bfd/coffgen.c
index 3e0fbc6184f..aab41c34ec7 100644
--- a/bfd/coffgen.c
+++ b/bfd/coffgen.c
@@ -1976,19 +1976,25 @@ coff_get_normalized_symtab (bfd *abfd)
 long
 coff_get_reloc_upper_bound (bfd *abfd, sec_ptr asect)
 {
-  if (bfd_get_format (abfd) != bfd_object)
+  size_t count, raw;
+
+  count = asect->reloc_count;
+  if (count >= LONG_MAX / sizeof (arelent *)
+      || _bfd_mul_overflow (count, bfd_coff_relsz (abfd), &raw))
     {
-      bfd_set_error (bfd_error_invalid_operation);
+      bfd_set_error (bfd_error_file_too_big);
       return -1;
     }
-#if SIZEOF_LONG == SIZEOF_INT
-  if (asect->reloc_count >= LONG_MAX / sizeof (arelent *))
+  if (!bfd_write_p (abfd))
     {
-      bfd_set_error (bfd_error_file_too_big);
-      return -1;
+      ufile_ptr filesize = bfd_get_file_size (abfd);
+      if (filesize != 0 && raw > filesize)
+	{
+	  bfd_set_error (bfd_error_file_truncated);
+	  return -1;
+	}
     }
-#endif
-  return (asect->reloc_count + 1L) * sizeof (arelent *);
+  return (count + 1) * sizeof (arelent *);
 }
 
 asymbol *
diff --git a/bfd/elf64-sparc.c b/bfd/elf64-sparc.c
index e9f03cf8e3a..fb4483dcd17 100644
--- a/bfd/elf64-sparc.c
+++ b/bfd/elf64-sparc.c
@@ -37,14 +37,25 @@
 static long
 elf64_sparc_get_reloc_upper_bound (bfd *abfd ATTRIBUTE_UNUSED, asection *sec)
 {
-#if SIZEOF_LONG == SIZEOF_INT
-  if (sec->reloc_count >= LONG_MAX / 2 / sizeof (arelent *))
+  size_t count, raw;
+
+  count = sec->reloc_count;
+  if (count >= LONG_MAX / 2 / sizeof (arelent *)
+      || _bfd_mul_overflow (count, sizeof (Elf64_External_Rela), &raw))
     {
       bfd_set_error (bfd_error_file_too_big);
       return -1;
     }
-#endif
-  return (sec->reloc_count * 2L + 1) * sizeof (arelent *);
+  if (!bfd_write_p (abfd))
+    {
+      ufile_ptr filesize = bfd_get_file_size (abfd);
+      if (filesize != 0 && raw > filesize)
+	{
+	  bfd_set_error (bfd_error_file_truncated);
+	  return -1;
+	}
+    }
+  return (count * 2 + 1) * sizeof (arelent *);
 }
 
 static long
diff --git a/bfd/mach-o.c b/bfd/mach-o.c
index 5279343768c..664ff44a8e7 100644
--- a/bfd/mach-o.c
+++ b/bfd/mach-o.c
@@ -1407,17 +1407,27 @@ bfd_mach_o_write_dyld_info (bfd *abfd, bfd_mach_o_load_command *command)
 }
 
 long
-bfd_mach_o_get_reloc_upper_bound (bfd *abfd ATTRIBUTE_UNUSED,
-				  asection *asect)
+bfd_mach_o_get_reloc_upper_bound (bfd *abfd, asection *asect)
 {
-#if SIZEOF_LONG == SIZEOF_INT
-   if (asect->reloc_count >= LONG_MAX / sizeof (arelent *))
+  size_t count, raw;
+
+  count = asect->reloc_count;
+  if (count >= LONG_MAX / sizeof (arelent *)
+      || _bfd_mul_overflow (count, BFD_MACH_O_RELENT_SIZE, &raw))
     {
       bfd_set_error (bfd_error_file_too_big);
       return -1;
     }
-#endif
- return (asect->reloc_count + 1L) * sizeof (arelent *);
+  if (!bfd_write_p (abfd))
+    {
+      ufile_ptr filesize = bfd_get_file_size (abfd);
+      if (filesize != 0 && raw > filesize)
+	{
+	  bfd_set_error (bfd_error_file_truncated);
+	  return -1;
+	}
+    }
+  return (count + 1) * sizeof (arelent *);
 }
 
 /* In addition to the need to byte-swap the symbol number, the bit positions
diff --git a/bfd/pdp11.c b/bfd/pdp11.c
index 9ef63cc311c..de9c8690e20 100644
--- a/bfd/pdp11.c
+++ b/bfd/pdp11.c
@@ -2125,13 +2125,7 @@ NAME (aout, canonicalize_reloc) (bfd *abfd,
 long
 NAME (aout, get_reloc_upper_bound) (bfd *abfd, sec_ptr asect)
 {
-  bfd_size_type count;
-
-  if (bfd_get_format (abfd) != bfd_object)
-    {
-      bfd_set_error (bfd_error_invalid_operation);
-      return -1;
-    }
+  size_t count, raw;
 
   if (asect->flags & SEC_CONSTRUCTOR)
     count = asect->reloc_count;
@@ -2147,11 +2141,21 @@ NAME (aout, get_reloc_upper_bound) (bfd *abfd, sec_ptr asect)
       return -1;
     }
 
-  if (count >= LONG_MAX / sizeof (arelent *))
+  if (count >= LONG_MAX / sizeof (arelent *)
+      || _bfd_mul_overflow (count, obj_reloc_entry_size (abfd), &raw))
     {
       bfd_set_error (bfd_error_file_too_big);
       return -1;
     }
+  if (!bfd_write_p (abfd))
+    {
+      ufile_ptr filesize = bfd_get_file_size (abfd);
+      if (filesize != 0 && raw > filesize)
+	{
+	  bfd_set_error (bfd_error_file_truncated);
+	  return -1;
+	}
+    }
   return (count + 1) * sizeof (arelent *);
 }
 

-- 
Alan Modra
Australia Development Lab, IBM

                 reply	other threads:[~2022-11-10 10:11 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=Y2zOaxv1jkhwTIAi@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).