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 8CF6B219A94; Tue, 6 May 2025 07:39:30 +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=1746517170; cv=none; b=eb+0Hvu6oHRWJvwRgeNXDTBGaQ5wiTiRoow6IE0i1+AJbhJPEVWPMzy752xVp3NjIft7wWEm3iOizsIoXaiLggSK0SVGXATiod1a+xtWll1AinV4bnbwIQ0fBi0ywRDxeb9UWRG16Ox9JnosL4N4x8BsKx1G1Q/YDWzOlewxHXM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746517170; c=relaxed/simple; bh=ldajszjlmAJBEpZ7WGRkd+NEPH8q2U32qIt+60788A8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=jf8WJpMsbee+UHoLmUZUMOwpwrPErDputnsB1vJZZk20SP12EwWP9uoEccaYjEaYVxY29ilHeSL0H60fTdtQuEPt2uyo/TdbY52nYaxbJ4mcZUx/YEosFi835Ij0BZW4nVKqUM8/sRM4o6xNA+17gpg/9gwWX3k1fX5R1/01uds= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TpEZgMWt; 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="TpEZgMWt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AA4E3C4CEE4; Tue, 6 May 2025 07:39:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1746517169; bh=ldajszjlmAJBEpZ7WGRkd+NEPH8q2U32qIt+60788A8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=TpEZgMWtRdVUAcq5WPuB3opmprM3oi218jk02ZJLh1AM5Fowc2zzm7ClsB6JQkLdg WcdcDUvSLsWm7OAxM/fjV4cB8aj96mm9Qzr2YxyKiYAPFtZGWWuhxBeJMO3cFxny57 xStUmBf/jNAbGPAY054+tfLKAJoRYQxLvZElEDme4ZYktVXu7Jv7MuwF5Zc06R2Yvk XqgvK2LaYbg+ackwJr5GK7551Dv45RTP9xY3Eetc2tgovd0S+pEQQQV8XFZVmaGR1j 6DEOmpx0LJHrIcy5N7qpfEplsuCDsjpd6BFsXaZuHSs+7w1vS/q2xwL1TCxY2JPuYR PqdQ0D4c6t05g== Date: Tue, 6 May 2025 09:39:22 +0200 From: Christian Brauner To: Jann Horn Cc: Kuniyuki Iwashima , alexander@mihalicyn.com, bluca@debian.org, daan.j.demeyer@gmail.com, davem@davemloft.net, david@readahead.eu, edumazet@google.com, horms@kernel.org, jack@suse.cz, kuba@kernel.org, lennart@poettering.net, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, me@yhndnzj.com, netdev@vger.kernel.org, oleg@redhat.com, pabeni@redhat.com, viro@zeniv.linux.org.uk, zbyszek@in.waw.pl Subject: Re: [PATCH RFC v3 08/10] net, pidfs, coredump: only allow coredumping tasks to connect to coredump socket Message-ID: <20250506-zertifikat-teint-d866c715291a@brauner> References: <20250505193828.21759-1-kuniyu@amazon.com> <20250505194451.22723-1-kuniyu@amazon.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: > ("a kernel socket" is not necessarily the same as "a kernel socket > intended for core dumping") Indeed. The usermodehelper is a kernel protocol. Here it's the task with its own credentials that's connecting to a userspace socket. Which makes this very elegant because it's just userspace IPC. No one is running around with kernel credentials anywhere.