Re: Make bfd_mach_o_archive_p more robust

[Tristan Gingold <gingold at adacore dot com>]

On Jan 27, 2009, at 3:29 PM, Andreas Schwab wrote:

> Mach-O fat archives and Java bytecode files have the same magic  
> number.
> Make sure bfd_mach_o_archive_p does not match the latter by checking
> that the number of architectures is reasonable.  This is the same
> heuristic that file(1) uses.

Fine to me (although I can't yet approve it).

Tristan.

> Andreas.
>
> 2009-01-27  Andreas Schwab  <schwab@suse.de>
>
> 	* mach-o.c (bfd_mach_o_archive_p): Restrict the number of
> 	architectures in the archive.
>
> --- bfd/mach-o.c	07 Jan 2009 09:44:50 +0100	1.31
> +++ bfd/mach-o.c	27 Jan 2009 15:28:33 +0100	
> @@ -2098,6 +2098,11 @@ bfd_mach_o_archive_p (bfd *abfd)
>   adata->nfat_arch = bfd_getb32 (buf + 4);
>   if (adata->magic != 0xcafebabe)
>     goto error;
> +  /* Avoid matching Java bytecode files, which have the same magic  
> number.
> +     In the Java bytecode file format this field contains to the JVM
> +     version, which starts at 43.0.  */
> +  if (adata->nfat_arch > 30)
> +    goto error;
>
>   adata->archentries =
>     bfd_alloc (abfd, adata->nfat_arch * sizeof  
> (mach_o_fat_archentry));
>
> --
> Andreas Schwab, SuSE Labs, schwab@suse.de
> SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
> PGP key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276  
> 4ED5
> "And now for something completely different."