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Fri, 13 Dec 2024 11:50:31 -0800 (PST) Message-ID: <3464006e-e1a5-48e4-b229-4c1c8609164f@kernel.dk> Date: Fri, 13 Dec 2024 12:50:30 -0700 Precedence: bulk X-Mailing-List: linux-btrfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 3/3] btrfs: don't read from userspace twice in btrfs_uring_encoded_read() To: Mark Harmstone , linux-btrfs@vger.kernel.org, io-uring@vger.kernel.org References: <20241213184444.2112559-1-maharmstone@fb.com> <20241213184444.2112559-3-maharmstone@fb.com> Content-Language: en-US From: Jens Axboe In-Reply-To: <20241213184444.2112559-3-maharmstone@fb.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 12/13/24 11:44 AM, Mark Harmstone wrote: > If we return -EAGAIN the first time because we need to block, > btrfs_uring_encoded_read() will get called twice. Take a copy of args > the first time, to prevent userspace from messing around with it. Looks good to me, however I think you'd want to add: Reported-by: Jens Axboe Fixes: 34310c442e17 ("btrfs: add io_uring command for encoded reads (ENCODED_READ ioctl)") to the tags, but probably whoever applies this can do that. -- Jens Axboe