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<2807E5FD2F6FDA4886F6618EAC48510E79E66216@CRSMSX101.amr.corp.intel.com> X-Nvconfidentiality: public From: John Hubbard Message-ID: <746b2412-f48a-9722-2763-253a1b9c899d@nvidia.com> Date: Fri, 2 Aug 2019 12:25:01 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <2807E5FD2F6FDA4886F6618EAC48510E79E66216@CRSMSX101.amr.corp.intel.com> X-Originating-IP: [10.124.1.5] X-ClientProxiedBy: HQMAIL104.nvidia.com (172.18.146.11) To HQMAIL107.nvidia.com (172.20.187.13) Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1564774001; bh=rRhheBqnK3+cjDjuz6CHnpsz5YflbO5z8PXp1A2YK5w=; h=X-PGP-Universal:Subject:To:CC:References:X-Nvconfidentiality:From: Message-ID:Date:User-Agent:MIME-Version:In-Reply-To: X-Originating-IP:X-ClientProxiedBy:Content-Type:Content-Language: Content-Transfer-Encoding; b=byi/JLB7CNtV06561y8XoJ3SAPfLWvMAReG7pbHQL4vyYMWIeKNh0N7pvRnXFQG1L qdrcKeqyYLdfyHlBvNt3iltX04f4l9yslTmpDdtWvq1t3b7bkuO+rrbkZHys+WsmhV 6Aa9W+8qQAz5X83c7tyDcDc6Mg36wKOuzq27pabbfn+69ez0SBMHEuaNtlKh20Fcaj gTip6LdymKj+uFDjnVTxb7sYVNWRS9rebCu5gBiFOf/CT8TUXKtD/8+Sk9b10OKO7l 1Y0kk6maXEh1JdSy6qqRDc1JYyIdeVQu9Kdnt4cKXn6PzYq3IXSks/FI+pwJb3dRVj 9ZhtT6T5hfRNQ== Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org On 8/2/19 9:09 AM, Weiny, Ira wrote: >> >> On 02.08.19 07:48, John Hubbard wrote: >>> On 8/1/19 9:36 PM, Juergen Gross wrote: >>>> On 02.08.19 04:19, john.hubbard@gmail.com wrote: >>>>> From: John Hubbard >>> ... >>> If that's not the case (both here, and in 3 or 4 other patches in this >>> series, then as you said, I should add NULL checks to put_user_pages() >>> and put_user_pages_dirty_lock(). >> >> In this case it is not correct, but can easily be handled. The NULL case can >> occur only in an error case with the pages array filled partially or not at all. >> >> I'd prefer something like the attached patch here. > > I'm not an expert in this code and have not looked at it carefully but that patch does seem to be the better fix than forcing NULL checks on everyone. > OK, I'll use Juergen's approach, and also check for that pattern in the other patches. thanks, -- John Hubbard NVIDIA