linux-kernel - Re: [PATCH v2 3/5] objtool: Add support for annotated jump tables

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAMj1kXG1K2ka+ygUbRNwGvwFFMuOSXxawpHfCPmZjYSY2weDpA@mail.gmail.com>
Date: Fri, 11 Oct 2024 08:29:48 +0200
From: Ard Biesheuvel <ardb@...nel.org>
To: Josh Poimboeuf <jpoimboe@...nel.org>
Cc: Ard Biesheuvel <ardb+git@...gle.com>, linux-kernel@...r.kernel.org, llvm@...ts.linux.dev, 
	keescook@...omium.org, linux-hardening@...r.kernel.org, nathan@...nel.org, 
	Peter Zijlstra <peterz@...radead.org>, Jan Beulich <jbeulich@...e.com>, 
	"Jose E. Marchesi" <jemarch@....org>, Kees Cook <kees@...nel.org>
Subject: Re: [PATCH v2 3/5] objtool: Add support for annotated jump tables

On Thu, 10 Oct 2024 at 22:15, Josh Poimboeuf <jpoimboe@...nel.org> wrote:
>
> On Thu, Oct 10, 2024 at 02:28:05PM +0200, Ard Biesheuvel wrote:
> > +++ b/tools/objtool/arch/x86/special.c
> > @@ -115,30 +115,51 @@ struct reloc *arch_find_switch_table(struct objtool_file *file,
> >       struct reloc  *text_reloc, *rodata_reloc;
> >       struct section *table_sec;
> >       unsigned long table_offset;
> > +     struct symbol *sym;
> >
> >       /* look for a relocation which references .rodata */
> >       text_reloc = find_reloc_by_dest_range(file->elf, insn->sec,
> >                                             insn->offset, insn->len);
>
> Hm, we can probably put insn_reloc() in check.h and use that here to
> take advantage of its caching for the no_reloc case.
>

insn_reloc() filters out R_*_NONE relocations, for the reasons pointed
out in the commit log.