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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Pavel Begunkov' <asml.silence@gmail.com>,
        Jens Axboe <axboe@kernel.dk>,
        "io-uring@vger.kernel.org" <io-uring@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [PATCH] io_uring: fix iovec leaks
Thread-Topic: [PATCH] io_uring: fix iovec leaks
Thread-Index: AQHV3emh7zgsynhUKk2BR9GeKazohKgVyZ8A
Date:   Tue, 11 Feb 2020 10:07:06 +0000
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From: Pavel Begunkov
> Sent: 07 February 2020 19:05
> Allocated iovec is freed only in io_{read,write,send,recv)(), and just
> leaves it if an error occured. There are plenty of such cases:
> - cancellation of non-head requests
> - fail grabbing files in __io_queue_sqe()
> - set REQ_F_NOWAIT and returning in __io_queue_sqe()
> - etc.
> 
> Add REQ_F_NEED_CLEANUP, which will force such requests with custom
> allocated resourses go through cleanup handlers on put.

This looks horribly fragile.

	David

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