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Subject: Re: [PATCH] Fix io_read() and io_write() when io_import_fixed() is
 used.
To:     David Laight <David.Laight@ACULAB.COM>
Cc:     LKML <linux-kernel@vger.kernel.org>
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 <3d5daf51252846cb851bf37d18842c4c@AcuMS.aculab.com>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <0db5b894-1914-1970-677e-01cdb8c93254@kernel.dk>
Date:   Tue, 4 Feb 2020 07:07:00 -0700
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On 2/4/20 7:05 AM, David Laight wrote:
> From: Jens Axboe
>> Sent: 04 February 2020 14:01
>> On 2/4/20 4:20 AM, David Laight wrote:
>>> io_import_fixed() returns 0 on success so io_import_iovec() may
>>> not return the length of the transfer.
>>>
>>> Instead always use the value from iov_iter_count()
>>> (Which is called at the same place.)
>>>
>>> Fixes 9d93a3f5a (modded by 491381ce0) and 9e645e110.
>>
>> What kernel is this against? This shouldn't be an issue
>> in anything newer than 5.3-stable.
> 
> Sources are 5.4.0-rc7.
> So not entirely 'the latest'.
> I didn't update late in the 5.5 cycle and won't until
> we get to rc4 (or so).

Ah ok, I think that's why. 5.4-stable will have a fix, 5.4.0
probably not. 5.5-rc and forward should be fine.

-- 
Jens Axboe