From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8CCF620B806; Wed, 28 May 2025 23:00:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748473206; cv=none; b=AkVu7UVm5ueEBY0iA52rZV6yC/NShh487Td68xzecKnXTVPPNZivyHT+vGNo/Vayau330/ou/Mqz7shUrYLiFY1pN9dhZo6fSNVdwT/bW7oevVvS+JpzZqkKX3+Tqp62T1vYz0oS9YOLxGvK549KZb0sE9UWmIrttnuR8Yuh6mk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748473206; c=relaxed/simple; bh=xugXewHqc3q1cop251f4ND/MS9iKw3qYkpWghA2m+i8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=CazvFX/ibk0Oj39rJ/uACIQ0lxBqzy8tLJgP1Os2oQ8dnxoImPM91gMK3XUTkgve2OlljNO92AHLPpvSmbByJ6dohZ9sh6V8pEru992zOKBFytRK0dJ9D0Yx7aJfOz8UQqwdUi4z9ETOlvAAqS/rbPREHgCWJJOkS+aqrqjBAd0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pRzJuyXv; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="pRzJuyXv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F2701C4CEE3; Wed, 28 May 2025 23:00:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1748473206; bh=xugXewHqc3q1cop251f4ND/MS9iKw3qYkpWghA2m+i8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=pRzJuyXvagDUNcrsTFHDUikt4P4Njr2MVvdguw+JE2AlCrSGxMo+//0IY6DE+j1Xk pugrmgZeUFJx5i3+QpsnIOnacLsPLt08TY2f0CvCBSvmumy5TiWwgnTRKSH5876Nug 5dK6uTFGYlVQ7G1r+9eJfCBw6x9OHkt4dNqEAqBdj4rpXHidKCMK/7VYTjfCGo/JLH d9RbQ+QoU0NAzjuz8gvAH47xzHFAkisipD1Wax/oEykrajdzgU4aVl5SVbas1QDOxX zitEbrzUVMHRucafzPdStW0S4UQuEZ1ULpzmSnlQ0B9vk9nimKJiIeRCcSqAvrmvKQ I19N1dHDDtHeQ== Date: Wed, 28 May 2025 16:00:03 -0700 From: Kees Cook To: Nathan Chancellor Cc: Justin Stitt , Eric Biggers , Arnd Bergmann , Jann Horn , Marco Elver , llvm@lists.linux.dev, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] ubsan: integer-overflow: depend on BROKEN to keep this out of CI Message-ID: <202505281559.FD37A978F@keescook> References: <20250528182616.work.296-kees@kernel.org> <20250528213223.GA3885532@ax162> Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250528213223.GA3885532@ax162> On Wed, May 28, 2025 at 02:32:23PM -0700, Nathan Chancellor wrote: > On Wed, May 28, 2025 at 11:26:22AM -0700, Kees Cook wrote: > > Depending on !COMPILE_TEST isn't sufficient to keep this feature out of > > CI because we can't stop it from being included in randconfig builds. > > This feature is still highly experimental, and is developed in lock-step > > with Clang's Overflow Behavior Types[1]. Depend on BROKEN to keep it > > from being enabled by anyone not expecting it. > > > > Link: https://discourse.llvm.org/t/rfc-v2-clang-introduce-overflowbehaviortypes-for-wrapping-and-non-wrapping-arithmetic/86507 [1] > > Signed-off-by: Kees Cook > > Should this have a 'Cc: stable@vger.kernel.org' on it? There might not > be much randconfig testing on stable but it is still very much possible > for some random user to turn this on and report problems. Ah yeah, I should probably do this via a proper Fixes: tag. I'll add this. > Regardless of that though, I think this is a good idea with how much of > this feature is still being ironed out. > > Reviewed-by: Nathan Chancellor Thanks! > > Once this lands, I plan to mark all issues in the CBL issue tracker that > came about from UBSAN_INTEGER_WRAP as 'have a workaround applied' since > it will not be possible for regular users to hit them but you may > consider notating them in case they need to be addressed before the > feature can be reenabled. Sounds good! -Kees -- Kees Cook