From: Andrew Morton <akpm@linux-foundation.org>
To: Pengcheng Yang <yangpc@wangsu.com>
Cc: gregkh@linuxfoundation.org, jannh@google.com,
viro@zeniv.linux.org.uk, linux-kernel@vger.kernel.org
Subject: Re: [PATCH RESEND] kernel/relay.c: fix read_pos error when multiple readers
Date: Thu, 23 Jan 2020 17:23:21 -0800 [thread overview]
Message-ID: <20200123172321.0ef6744e784692585f9843b3@linux-foundation.org> (raw)
In-Reply-To: <1579691175-28949-1-git-send-email-yangpc@wangsu.com>
On Wed, 22 Jan 2020 19:06:15 +0800 Pengcheng Yang <yangpc@wangsu.com> wrote:
> When reading, read_pos should start with bytes_consumed,
> not file->f_pos. Because when there is more than one reader,
> the read_pos corresponding to file->f_pos may have been consumed,
> which will cause the data that has been consumed to be read
> and the bytes_consumed update error.
That sounds fairly serious. Are you able to describe a userspace setup
which will trigger this? Do you have any test code which is able to
demonstrate the bug?
We really should have a relay testcase in tools/testing, but relay came
along before we became diligent about this.
next prev parent reply other threads:[~2020-01-24 1:23 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-22 11:06 Pengcheng Yang
2020-01-24 1:23 ` Andrew Morton [this message]
2020-03-20 11:04 ` Pengcheng Yang
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