linux-kernel - RE: [PATCH] io_uring: fix iovec leaks

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Message-ID: <1255e56851a54c8c805695f1160bec9f@AcuMS.aculab.com>
Date:   Tue, 11 Feb 2020 10:07:06 +0000
From:   David Laight <David.Laight@...LAB.COM>
To:     'Pavel Begunkov' <asml.silence@...il.com>,
        Jens Axboe <axboe@...nel.dk>,
        "io-uring@...r.kernel.org" <io-uring@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: RE: [PATCH] io_uring: fix iovec leaks

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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