[PATCH] d: fix ASAN in option processing

[Iain Buclaw]

Excerpts from Martin Liška's message of November 25, 2021 2:59 pm:
> Fixes:
> 
> ==129444==ERROR: AddressSanitizer: global-buffer-overflow on address 0x00000666ca5c at pc 0x000000ef094b bp 0x7fffffff8180 sp 0x7fffffff8178
> READ of size 4 at 0x00000666ca5c thread T0
>      #0 0xef094a in parse_optimize_options ../../gcc/d/d-attribs.cc:855
>      #1 0xef0d36 in d_handle_optimize_attribute ../../gcc/d/d-attribs.cc:916
>      #2 0xef107e in d_handle_optimize_attribute ../../gcc/d/d-attribs.cc:887
>      #3 0xff85b1 in decl_attributes(tree_node**, tree_node*, int, tree_node*) ../../gcc/attribs.c:829
>      #4 0xef2a91 in apply_user_attributes(Dsymbol*, tree_node*) ../../gcc/d/d-attribs.cc:427
>      #5 0xf7b7f3 in get_symbol_decl(Declaration*) ../../gcc/d/decl.cc:1346
>      #6 0xf87bc7 in get_symbol_decl(Declaration*) ../../gcc/d/decl.cc:967
>      #7 0xf87bc7 in DeclVisitor::visit(FuncDeclaration*) ../../gcc/d/decl.cc:808
>      #8 0xf83db5 in DeclVisitor::build_dsymbol(Dsymbol*) ../../gcc/d/decl.cc:146
> 
> for the following test-case: gcc/testsuite/gdc.dg/attr_optimize1.d.
> 
> Ready for master?

Thanks, looks OK to me, does it need backporting as well?

Iain.



> Thanks,
> Martin
> 
> gcc/d/ChangeLog:
> 
> 	* d-attribs.cc (parse_optimize_options): Check index before
> 	accessing cl_options.
> ---
>   gcc/d/d-attribs.cc | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/gcc/d/d-attribs.cc b/gcc/d/d-attribs.cc
> index d81b7d122f7..1ec800526f7 100644
> --- a/gcc/d/d-attribs.cc
> +++ b/gcc/d/d-attribs.cc
> @@ -852,7 +852,9 @@ parse_optimize_options (tree args)
>     unsigned j = 1;
>     for (unsigned i = 1; i < decoded_options_count; ++i)
>       {
> -      if (! (cl_options[decoded_options[i].opt_index].flags & CL_OPTIMIZATION))
> +      unsigned opt_index = decoded_options[i].opt_index;
> +      if (opt_index >= cl_options_count
> +	  && ! (cl_options[opt_index].flags & CL_OPTIMIZATION))
>   	{
>   	  ret = false;
>   	  warning (OPT_Wattributes,
> -- 
> 2.34.0
> 
>