From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792697091; b=J5wiSSKNUTbevPH3DtdljiiIlEbxN6VxIpaEz2jXha7fbMTU4RP/QtlSgesbLL7lk5Y0 PD8m+mwQzPculaejGpuSRVwVuPqkVDbjT+Sn800ZkXhtIaF8SPtIkkdIWE27k7lzLIc2d fCzVLxn24om4dzcKgjwbr7xuOx5EaLZwrEUfsrbJl1/hQnkJILZXmIMwa/r+QuQOKO5aj O0M/lqGYRmwjmmA2DP39OR3N+yXJrLzkDSOOAqseesPENMscjvrVZL9yGSc7BmGcLVSAm F+GSmLG6KTDgB6PMpa0xcWv/rNGHumwc5okqnhkP5KDhAG9GqGDYhiKm1xvlhy1IeiA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792697091; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=rYWHiFbQm2dwxFsz4ZREOzfxKwGWqmDgU1C9LjFjhyk=; b=RQiTjFziGULhAbYZxVVJIPwJoVUWV4YPb+Y+8RDJ8O+Vp+tzJDI4QWS4RU5Bz8HXc7SH aw2R6b3Ja5HB0n7EbWg7ypU5RXETDu3AEAtVNNTjUfzd1v3/IcG/DVj2jYvHA8TJ6zRKr nuoaCLX3iZqHI84m2wf7UqEaxVrdh5VIJ/FUV+mBxT+iblLF/yoMqvBorfhugp1zKAGhY l3tgTX5gZjXF52vGjpfQUpoapz1ThyWn0LbPFu0coYOzTJRIvjzb/fzgfB/jh0bCbatrR chrnLYI+I77mLgknpZ/LbYLgwDtGjWescihpqAgxJ9e2o3db67mL5yVTspJTj8V5IBw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Alb4+QzG; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0C293606A319 for ; Thu, 22 Oct 2026 19:24:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Alb4+QzG Received: by smtp.kernel.org (Postfix) with ESMTPSA id B2FEE1F01825; Thu, 22 Oct 2026 19:24:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792697090; bh=rYWHiFbQm2dwxFsz4ZREOzfxKwGWqmDgU1C9LjFjhyk=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=Alb4+QzGmOybq6zgaMhrQhf4zE7DSXgf1WrNIQIK8f/OYx0GUOTPEBTy3h9fMJ1QT XvWH3pwEgbsS8BBGjmmf/TqjBWmC8zcsDdkYTo3QT7MKatAMxPi+HHfjLep44VC1Gr X8+ebnr087sDgmsr6Yt929X6/wSvoZJLKVfxec3ej0B40lTZ1Gv/BdNl51bAREvfNm ehbMRz+tGxpRYBYJ2FIOEUgJTtqDhzBASYAEoji97k6Ty7G9iFqUb3WpoAOsFKgOr/ XjKeB0gGASsKvdKZZzwQz7taBmbJbD8zZYU/i7OST0ueuFQiKq/1qB7lK68xxYhTHH 3jFAxWYbQgRRg== Date: Thu, 22 Oct 2026 12:24:50 -0700 From: Kees Cook To: Martin Jambor Cc: Jan Hubicka , gcc-patches@gcc.gnu.org, linux-hardening@vger.kernel.org, Richard Biener Subject: Re: [PATCH] ipa-icf: Step to the next caller past a thunk in redirect_all_callers Message-ID: <202610221224.60CF7CE4B@keescook> References: <20261015194513.i.609-kees@kernel.org> X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Tue, Oct 20, 2026 at 05:14:25PM +0200, Martin Jambor wrote: > Hi, > > On Mon, Oct 19 2026, Richard Biener wrote: > > On Thu, 15 Oct 2026, Kees Cook wrote: > > > >> redirect_all_callers walks the callers of N, but steps past a thunk > >> caller with next_callee, the next call the thunk makes. A thunk makes > >> only that one call, so the walk ends there, and so the callers after > >> the thunk in the list would not be redirected. This came with the thunk > >> check in commit 17d1bf760f8 ("re PR target/65263"). > > > > Huh. This looks obvious to me, thus OK unless Jan or Martin object > > soon. > > This is fairly obviously OK. > > Thanks for catching this! I don't have commit access, so if someone can do that bit for me, I'd appreciate it. :) Thanks! -- Kees Cook