Re: [PATCH] elf: Don't call fatal_error in _dl_signal_error

[Florian Weimer <fweimer@redhat.com>]

* H. J. Lu:

> Don't call fatal_error in _dl_signal_error since _dl_signal_error should
> only be called from _dl_catch_exception and get_catch should never return
> NULL.  Otherwise, fatal_error should be called directly instead.
> ---
>  elf/dl-catch.c | 13 ++++---------
>  1 file changed, 4 insertions(+), 9 deletions(-)
>
> diff --git a/elf/dl-catch.c b/elf/dl-catch.c
> index 2109516dba..a023555165 100644
> --- a/elf/dl-catch.c
> +++ b/elf/dl-catch.c
> @@ -117,16 +117,11 @@ _dl_signal_error (int errcode, const char *objname, const char *occasion,
>    if (! errstring)
>      errstring = N_("DYNAMIC LINKER BUG!!!");
>  
> -  if (lcatch != NULL)
> -    {
> -      _dl_exception_create (lcatch->exception, objname, errstring);
> -      *lcatch->errcode = errcode;
> +  _dl_exception_create (lcatch->exception, objname, errstring);
> +  *lcatch->errcode = errcode;
>  
> -      /* We do not restore the signal mask because none was saved.  */
> -      __longjmp (lcatch->env[0].__jmpbuf, 1);
> -    }
> -  else
> -    fatal_error (errcode, objname, occasion, errstring);
> +  /* We do not restore the signal mask because none was saved.  */
> +  __longjmp (lcatch->env[0].__jmpbuf, 1);
>  }
>  rtld_hidden_def (_dl_signal_error)

elf/ld.so program-does-not-exist triggers are null pointer dereference
with this patch.

I'll post a proper test case for this, looks like we have a gap here.

Thanks,
Florian