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 AF7B71CDFD5 for ; Mon, 2 Jun 2025 09:32:47 +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=1748856767; cv=none; b=ZPJ8mgnySg3/jQKVzsVn+Z2JsZIayANv11Fc/GQVnqF/P82MS/iF0JcBnieAY0zTiHRJ1bv2UIjSq39ZpufTmMXBcVmLZx68Fis6HVz5X2sirVlScN5hKenLRSCnsGMDsl8Ky1MEogv2uHaWXDjEm6S9Ekyhl9djmEKIsoaSkig= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748856767; c=relaxed/simple; bh=1X4L7u/3s7ZJTyFnSRfmV19dbdOdnbPxBE8rxS+z6HY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=uE04tmxHSlcEKS+zf6o5ojR+skUflYyFFwKVZN3A05e9y7UuVubQW5V8KmndklK/4og5H7MtQmBRlSucOyZUa7n45S7/LYDlIPI2nDp1VAhBmxiQ2jEiu0T2yS4STtK2fy/76idnpgdvQB3fKG/nz+PcBmffYkEbLZnpyp112N4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=SnuDzSsX; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="SnuDzSsX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CDFEFC4CEEB; Mon, 2 Jun 2025 09:32:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1748856767; bh=1X4L7u/3s7ZJTyFnSRfmV19dbdOdnbPxBE8rxS+z6HY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=SnuDzSsXDF5lcPy7XXtUZhnS43moNRjo+Bi2x56NDJkDWHnGFLDdqg7ncrIywMhqP OeUdJ9rsT580IdYA0a/FlHNIv2Yt6GJtADQypLqH6r7o3KEfnVshz30K651FWbbYXS /exaRk+BvospWnmK6MbYwxKbY+cSYSBisKrHYiBo= Date: Mon, 2 Jun 2025 11:32:44 +0200 From: Greg Kroah-Hartman To: Christian Brauner Cc: Luca Boccassi , stable@kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: Please consider backporting coredump %F patch to stable kernels Message-ID: <2025060211-egotistic-overnight-9d10@gregkh> References: <20250602-vulkan-wandbild-fb6a495c3fc3@brauner> Precedence: bulk X-Mailing-List: linux-fsdevel@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: <20250602-vulkan-wandbild-fb6a495c3fc3@brauner> On Mon, Jun 02, 2025 at 11:09:05AM +0200, Christian Brauner wrote: > On Fri, May 30, 2025 at 10:44:16AM +0100, Luca Boccassi wrote: > > Dear stable maintainer(s), > > > > The following series was merged for 6.16: > > > > https://lore.kernel.org/all/20250414-work-coredump-v2-0-685bf231f828@kernel.org/ > > > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c57f07b235871c9e5bffaccd458dca2d9a62b164 > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=95c5f43181fe9c1b5e5a4bd3281c857a5259991f > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b5325b2a270fcaf7b2a9a0f23d422ca8a5a8bdea > > > > This allows the userspace coredump handler to get a PIDFD referencing > > the crashed process. > > > > We have discovered that there are real world exploits that can be used > > to trick coredump handling userspace software to act on foreign > > processes due to PID reuse attacks: > > > > https://security-tracker.debian.org/tracker/CVE-2025-4598 > > > > We have fixed the worst case scenario, but to really and > > comprehensively fix the whole problem we need this new %F option. We > > have backported the userspace side to the systemd stable branch. Would > > it be possible to backport the above 3 patches to at least the 6.12 > > series, so that the next Debian stable can be fully covered? The first > > two are small bug fixes so it would be good to have them, and the > > third one is quite small and unless explicitly configured in the > > core_pattern, it will be inert, so risk should be low. > > I agree that we should try and backport this if Greg agrees we can do > this. v6.15 will be easy to do. Further back might need some custom work > though. Let's see what Greg thinks. Yes, seems like a good thing to backport to at least 6.12.y if possible. Is it just the above 3 commits? thanks, greg k-h