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Re: [PATCH] Missing string termination in elf-setup-vdso.h?

On Mon, Aug 19, 2013 at 07:14:24PM +0200, Andreas Arnez wrote:
> While trying to understand what information is stored for VDSOs in the
> link map, I stumbled upon what looks like a missing string termination
> bug.  It seems that this code is usually not reached; thus I'm not sure
> which systems are affected by this (potential) bug.
Looks  OK for me with possible improvement. A line after diff is

l->l_libname->name = l->l_name = memcpy (copy, dsoname, len);

If it was not elf I would say just use strdup. 
But xstrdup is found on several places of elf. Is xstrdup safe here?
> 2013-08-19  Andreas Arnez  <>
> 	* elf/setup-vdso.h (setup_vdso): Fix missing string termination.
> diff --git a/elf/setup-vdso.h b/elf/setup-vdso.h
> index a98dfec..056d885 100644
> --- a/elf/setup-vdso.h
> +++ b/elf/setup-vdso.h
> @@ -89,7 +89,7 @@ setup_vdso (struct link_map *main_map __attribute__ ((unused)),
>  	     addresses in the vsyscall DSO pages in writev() calls.  */
>  	  const char *dsoname = ((char *) D_PTR (l, l_info[DT_STRTAB])
>  				 + l->l_info[DT_SONAME]->d_un.d_val);
> -	  size_t len = strlen (dsoname);
> +	  size_t len = strlen (dsoname) + 1;
>  	  char *copy = malloc (len);
>  	  if (copy == NULL)
>  	    _dl_fatal_printf ("out of memory\n");

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