From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout.web.de (mout.web.de [212.227.15.4]) (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 D0BD7259C; Sun, 30 Jun 2024 18:01:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=212.227.15.4 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719770511; cv=none; b=esflLcepQCk7bT9ok+d3tFptrdRtqQut/Oz3XoYDIfy1ZenoCJnT37A1PRGAgxwn6xpTmIw4+nEbQvnlKfffG3xV6m942PDnkVp+Ltc5d6acMKguSnLusNs0wv4Rr7SDl2FEaZeQg8gOJKajg/5nl0mXAXn6QDr8G6jLCWzCrq8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719770511; c=relaxed/simple; bh=JM4ts4Lg+u1XZgCQxkJ32EGuA7iSoUrxdkoZR/5bRXk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=ciePGusA7N22/HER9in2pAoqmA1x2kDAHrGlwPCvj8CraSu4bnrT1a6b0wc6jMF4O+5Ehyab3+whrJLs9KkNsUauKFiSBGs6Y2A/CrYxgV4tcllQtyM5MogoChHowdP3WCdZIdXYDM2vhocy/nNAFzFvOlblqfmqztqAgP+h72Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=web.de; spf=pass smtp.mailfrom=web.de; dkim=pass (2048-bit key) header.d=web.de header.i=markus.elfring@web.de header.b=FqNB4rRP; arc=none smtp.client-ip=212.227.15.4 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=web.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=web.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=web.de header.i=markus.elfring@web.de header.b="FqNB4rRP" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=web.de; s=s29768273; t=1719770454; x=1720375254; i=markus.elfring@web.de; bh=2l5pzDpEunthmwraZ8MRcFVL/DiaIDsYVGK5RSImcgc=; h=X-UI-Sender-Class:Message-ID:Date:MIME-Version:Subject:To:Cc: References:From:In-Reply-To:Content-Type: Content-Transfer-Encoding:cc:content-transfer-encoding: content-type:date:from:message-id:mime-version:reply-to:subject: to; b=FqNB4rRPmpoZmTeZUtGks31irwq/sxmRR4g2EQlJvDaOKEaSm/ZJ3k426Pp3ZLE/ jn3dnCJe+qWetJeRivDkm/nBwUsNxbU1BZXuWk5qR9vK+cIFU4pKPfRbxjOyqOsC1 l1VKm0hDK1+yZyLf0YaNwNTWAvKdQvWMHXJI9xcnhwGoGTV0TKE2qUapKVnq5pUKJ 26NokycH2PpNif0U8ovQYUnE1F2jzcxsJNVKPSw0AMlgCziJn98cqCuvNtOScAu+z P/eHE5x9Iz1EhtS2Pk972TCkBVczbWMGp/0lzD4tcMRtkui9UYlV7aWVdXGOk5YgY FWyuEfjgSoDpxXBDpQ== X-UI-Sender-Class: 814a7b36-bfc1-4dae-8640-3722d8ec6cd6 Received: from [192.168.178.21] ([94.31.82.95]) by smtp.web.de (mrweb005 [213.165.67.108]) with ESMTPSA (Nemesis) id 1MYtwy-1ssreI2Cga-00P5bO; Sun, 30 Jun 2024 20:00:54 +0200 Message-ID: <55f0bd69-03a6-4a2f-94e0-6c62e2e3a6f8@web.de> Date: Sun, 30 Jun 2024 20:00:52 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [V4] cgroup/cpuset: Prevent UAF in proc_cpuset_show() To: Tejun Heo , Chen Ridong , cgroups@vger.kernel.org Cc: Aditya Kali , Johannes Weiner , =?UTF-8?Q?Michal_Koutn=C3=BD?= , Peter Zijlstra , Serge Hallyn , Waiman Long , Zefan Li , LKML References: <20240628013604.573498-1-chenridong@huawei.com> Content-Language: en-GB From: Markus Elfring In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:cTPgX2zg7g/i2MT8VqlgAlTZHTJNvHuMDr/05KvwiUnXVuksN0z NlWTIryGqdGe6Z8m93kRylnebBLPEJfFuc2bqDXj0G1nPkJRLDH1RsUxatXBvC9oyeNOnhg IaCqmM9nIvotL19mRygn9zJ2HH6Rqj01JQg8aVI4NS3m8L4GQ7+EVy0p1M606SR2f7me41d wrIexzT7rhuIc7i8do0AA== X-Spam-Flag: NO UI-OutboundReport: notjunk:1;M01:P0:sZuomuhfio4=;E3dx0FBev/VnnfLA+TD+f0rV1+f 4eEGWRRAk6EDUalWCzS3YO8f+G1OlEqMHZPvopLjRSGS2CAAp4NlfVYs02bWWkxsRywynVrhC yKf/bOHcv98yFK953doqAQy4gbU0BIK+G5v0ztBwNIt2G32jmF64CbfptSxz0JbdibSfb9sjx dsKXVxuMYDrgTb4CA9YwoLCcOoyFiaEEiJYg+LMzlXCCQq7um4UJ8HpdyeT/6S12CYStnenxs O8dxs+HWcQYLpnMxqOntUlIx4qtwff+plrH0c5W5XJa0VPk+1WmI+ZFQKGNSqBNJVfz4ccEZQ o+k9wshAn8wCiHwKokx4XLQ2P6HDWkKYaMDYKkPBEqxTcu7gElbmWWctb3+3cT9Ppd9pSUh00 znf3Cca3ykk3zMTtWxjk2Wv1nvznspKs9rE3G4ESUuXAZTj1EanFTfI4wnOM1WVNtRH2GAaul EXZAF5Aoz1XyPH3zLt8gYB0WEADqeojsbWzdpWGMCuDzxIk4qR89xLHHvcxBs146Q/hSU2TCT LHKEPcBCc3ya8dyaSjFqlp8ILVC6tgme0yCKfHGG9nYLt2Ai441Fsic3U+KKjLN2aB0OjtrM2 ZlLwVGlGaCLhsRvqJtFSnYrOjRV5xyGMhpSHjCrkZa74s+nvXta2Yivc5YddoKhx7CiThKSL0 zJ6skO7LFDbbWU3AqOthM8OvZfw0GzYnDXZ31q71If8bPV33eo1bmuGY5TlfwHt53hr0BgMvt aYBzW5md/MuM4NT5HuthY+1yeoeL1b2BbkTNXLtsJmvNll+/OAlRyRlAJ1z3HPHgjs4K2wXMI 8vMg5m2zCVp1O5D64s4T8MHT6IYHu2XFZLUMNtp+X83r4= >> Under which circumstances would you become interested to apply statemen= ts >> like the following? >> >> * guard(rcu)(); >> https://elixir.bootlin.com/linux/v6.10-rc5/source/include/linux/rcupd= ate.h#L1093 >> >> * guard(spinlock_irq)(&css_set_lock); >> https://elixir.bootlin.com/linux/v6.10-rc5/source/include/linux/spinl= ock.h#L567 > > I don't really care either way. I find such feedback interesting somehow. > Neither makes meaningful difference here. Would you like to support making the affected source code safer and a bit = more succinct? https://elixir.bootlin.com/linux/v6.10-rc5/source/kernel/cgroup/cpuset.c#L= 5034 Regards, Markus