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 8D2EE4A2C; Sun, 25 Aug 2024 05:54:43 +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=1724565283; cv=none; b=mNz/GnVuC6ENjE+XgMxir5wdl+0f5UpXOZ+iEKdKyph4eIUYyuHb5laQ3HWJiowxmQjC09D6eagylH4aUQ0BDVt7woB0M2AYwhg5lmimNY80uwPd7Gtkkp5HnDnGLbRFEo5De5pLdXZeWvPcVVxMzPVUbDa17ep25Eo+bxtpC/g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724565283; c=relaxed/simple; bh=owT9cjCQl8VaNV12SGllrJLyCpVWeh3HI13fm4EgNyk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=LKh2zv/cuR9HUCuA2lXVdgcUG9MBGK7oTrIJdsTmkrJilpXx+X9JQcYJLvsat8qEDrA2bK6USn/5LAe1zqGrSLO8j7byMIh+5gdhrHdF+da7mkK2w/DucowExFrr3CsXLVS74lpU83225pUikzOa23U/92v0XW6gVIx+D9xykS8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=vPUBDCun; 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="vPUBDCun" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C1BE6C32782; Sun, 25 Aug 2024 05:54:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1724565283; bh=owT9cjCQl8VaNV12SGllrJLyCpVWeh3HI13fm4EgNyk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=vPUBDCunCnhR0RMHL5bwRgTF9UmJr9T/j1knjJelphKRSD7KL1OADfiALMxz9hJk9 tWPAVkbZSqOcBj1v9S2fnSGE0bHP8kxWvTbzcibJXSuMD7TPVRt6DUOz672vk5i9Ns S3txXlf7YP2S4jeU/lglzHURV+krydripvAkpBjs= Date: Sun, 25 Aug 2024 07:54:40 +0200 From: Greg Kroah-Hartman To: Xia Fukun Cc: cve@kernel.org, linux-kernel@vger.kernel.org, linux-cve-announce@vger.kernel.org, "Zhangqiao (2012 lab)" , "Chenhui (Judy)" Subject: Re: CVE-2022-48921: sched/fair: Fix fault in reweight_entity Message-ID: <2024082539-balancing-rematch-d61d@gregkh> References: <2024082218-CVE-2022-48921-5016@gregkh> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Sat, Aug 24, 2024 at 05:52:05PM +0800, Xia Fukun wrote: > > On 2024/8/22 11:31, Greg Kroah-Hartman wrote: > > Description > > =========== > > > > In the Linux kernel, the following vulnerability has been resolved: > > > > sched/fair: Fix fault in reweight_entity > > > > Syzbot found a GPF in reweight_entity. This has been bisected to > > commit 4ef0c5c6b5ba ("kernel/sched: Fix sched_fork() access an invalid > > sched_task_group") > > > > There is a race between sched_post_fork() and setpriority(PRIO_PGRP) > > within a thread group that causes a null-ptr-deref in > > reweight_entity() in CFS. The scenario is that the main process spawns > > number of new threads, which then call setpriority(PRIO_PGRP, 0, -20), > > wait, and exit. For each of the new threads the copy_process() gets > > invoked, which adds the new task_struct and calls sched_post_fork() > > for it. > > > > > > The Linux kernel CVE team has assigned CVE-2022-48921 to this issue. > > > > Commit 13765de8148f ("sched/fair: Fix fault in reweight_entity") > is reverted by commit b1e8206582f9 ("sched: Fix yet more sched_fork() > races"). Since commit 13765de8148f only fixes a single instance > of this problem, not the whole class. > > I think the CVE-2022-48921 needs to adjust the corresponding commit > to commit b1e8206582f9 ("sched: Fix yet more sched_fork() races"). I think we just need to assign a new CVE to b1e8206582f9, as that was not backported to everywhere that 13765de8148f was applied, right? Wouldn't that be the correct thing to do as it did fix things in a different way. thanks, greg k-h