This is the mail archive of the binutils-cvs@sourceware.org mailing list for the binutils project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

[binutils-gdb] Fix excessive memory allocation attempts and possible integer overfloaws when attempting to read a C


https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=6cee897971d4d7cd37d2a686bb6d2aa3e759c8ca

commit 6cee897971d4d7cd37d2a686bb6d2aa3e759c8ca
Author: Nick Clifton <nickc@redhat.com>
Date:   Fri Nov 3 11:55:21 2017 +0000

    Fix excessive memory allocation attempts and possible integer overfloaws when attempting to read a COFF binary with a corrupt symbol count.
    
    	PR 22385
    	* coffgen.c (_bfd_coff_get_external_symbols): Check for an
    	overlarge raw syment count.
    	(coff_get_normalized_symtab): Likewise.

Diff:
---
 bfd/ChangeLog |  8 ++++++++
 bfd/coffgen.c | 17 +++++++++++++++--
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index b8cddd5..e857d2e 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,11 @@
+2017-11-03  Mingi Cho  <mgcho.minic@gmail.com>
+	    Nick Clifton  <nickc@redhat.com>
+
+	PR 22385
+	* coffgen.c (_bfd_coff_get_external_symbols): Check for an
+	overlarge raw syment count.
+	(coff_get_normalized_symtab): Likewise.
+
 2017-11-01  James Bowman  <james.bowman@ftdichip.com>
 
 	* archures.c: Add bfd_mach_ft32b.
diff --git a/bfd/coffgen.c b/bfd/coffgen.c
index 98363d0..81efd9b 100644
--- a/bfd/coffgen.c
+++ b/bfd/coffgen.c
@@ -1640,13 +1640,23 @@ _bfd_coff_get_external_symbols (bfd *abfd)
   size = obj_raw_syment_count (abfd) * symesz;
   if (size == 0)
     return TRUE;
+  /* Check for integer overflow and for unreasonable symbol counts.  */
+  if (size < obj_raw_syment_count (abfd)
+      || (bfd_get_file_size (abfd) > 0
+	  && size > bfd_get_file_size (abfd)))
+    
+    {
+      _bfd_error_handler (_("%B: corrupt symbol count: %#Lx"),
+			  abfd, obj_raw_syment_count (abfd));
+      return FALSE;
+    }
 
   syms = bfd_malloc (size);
   if (syms == NULL)
     {
       /* PR 21013: Provide an error message when the alloc fails.  */
-      _bfd_error_handler (_("%B: Not enough memory to allocate space for %Lu symbols"),
-			  abfd, size);
+      _bfd_error_handler (_("%B: not enough memory to allocate space for %#Lx symbols of size %#Lx"),
+			  abfd, obj_raw_syment_count (abfd), symesz);
       return FALSE;
     }
 
@@ -1794,6 +1804,9 @@ coff_get_normalized_symtab (bfd *abfd)
     return NULL;
 
   size = obj_raw_syment_count (abfd) * sizeof (combined_entry_type);
+  /* Check for integer overflow.  */
+  if (size < obj_raw_syment_count (abfd))
+    return NULL;
   internal = (combined_entry_type *) bfd_zalloc (abfd, size);
   if (internal == NULL && size != 0)
     return NULL;


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]