From: Rich Felker <dalias@libc.org>
To: Shiz <hi@shiz.me>
Cc: musl@lists.openwall.com, darkkirb@darkkirb.be
Subject: Re: [musl] [PATCH] Add support for LLVM's Control Flow Integrity (V2)
Date: Mon, 28 Dec 2020 20:26:56 -0500 [thread overview]
Message-ID: <20201229012656.GE22981@brightrain.aerifal.cx> (raw)
In-Reply-To: <F4C8EA33-9721-47A5-BEC6-5A29A7072989@shiz.me>
On Mon, Dec 28, 2020 at 06:01:45PM +0100, Shiz wrote:
> Hi,
>
> It seems to me guarding all of those with #ifdef __clang__ is not the optimal approach.
> What if another compilers decides to pick up the spec, or an older non-CFI
> Clang is used to compile? I think it's more logical to check the no_sanitize attribute
> with a functional test (like __has_attribute), and to just apply the used attribute
> unconditionally.
Regardless none of these changes belong in source files.
Assuming it actually can be made to work to begin with, the nocfi
stuff should be done on a file-granularity basis with per-target
CFLAGS += ...
The "used" attributes are working around some other problem, either a
bug in clang (sounds most likely) or lack of semantic usedness in musl
source, and should be fixed wherever the bug is not papered over.
Rich
next prev parent reply other threads:[~2020-12-29 1:27 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-27 17:53 [musl] [PATCH] Add support for LLVM's Control Flow Integrity Charlotte Delenk
2020-12-27 23:05 ` Fangrui Song
2020-12-28 0:56 ` Fangrui Song
2020-12-28 9:20 ` Charlotte Delenk
2020-12-28 13:17 ` [musl] [PATCH] Add support for LLVM's Control Flow Integrity (V2) Charlotte Delenk
2020-12-28 17:01 ` Shiz
2020-12-29 1:26 ` Rich Felker [this message]
2020-12-29 10:20 ` Charlotte Delenk
2020-12-29 11:56 ` [musl] [PATCH 1/2] Fix LTO shared library build on GCC and Clang Charlotte Delenk
2020-12-29 11:59 ` [musl] [PATCH 2/2] Add support for LLVM's Control Flow Integrity Charlotte Delenk
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20201229012656.GE22981@brightrain.aerifal.cx \
--to=dalias@libc.org \
--cc=darkkirb@darkkirb.be \
--cc=hi@shiz.me \
--cc=musl@lists.openwall.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://git.vuxu.org/mirror/musl/
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).