From: Dave Chinner <david@fromorbit.com>
To: Eric Sandeen <sandeen@redhat.com>
Cc: Jouko Orava <jouko.orava@helsinki.fi>,
linux-ext4@vger.kernel.org, Zheng Liu <gnehzuil.liu@gmail.com>
Subject: Re: Bug: Large writes can fail on ext4 if the write buffer is not empty
Date: Fri, 20 Apr 2012 12:12:11 +1000 [thread overview]
Message-ID: <20120420021211.GD9541@dastard> (raw)
In-Reply-To: <4F901E0C.3010008@redhat.com>
On Thu, Apr 19, 2012 at 09:15:40AM -0500, Eric Sandeen wrote:
> On 4/19/12 8:10 AM, Jouko Orava wrote:
> > I'd also like to point at the real bug here, in Jouni's original strace:
> >
> > writev(3, [{"\0\0\0\0\0\0\0\0", 8}, {"", 2147483648}], 2) = -2147483640
> >
> > The syscall returns a negative value, which is not the actual number of
> > bytes written (since it is 32-bit wrapped), and errno has not been
> > changed. There is no way for userspace to handle this result correctly!
> >
> > There is no way anyone sane should just gloss over this saying
> > "programmer fault, you're doing it wrong".
> > This is a real bug, and deserves fixing sooner rather than later.
>
> Agreed, I think Dave was a little to quick on the draw on his reply. :)
I was pointing the -EFAULT error in the second syscall which was
just being passed the 2GB sized buffer, not the above error from the
first syscall.
Cheers,
Dave.
--
Dave Chinner
david@fromorbit.com
next prev parent reply other threads:[~2012-04-20 2:12 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-04-12 14:47 Bug: Large writes can fail on ext4 if the write buffer is not empty Jouni Siren
2012-04-12 16:06 ` Zheng Liu
2012-04-12 20:20 ` Jan Kara
2012-04-13 1:22 ` [PATCH RESEND] ext4: change return value from int to ssize_t in ext4_file_write Zheng Liu
2012-05-22 19:44 ` Eric Sandeen
2012-05-28 22:08 ` Ted Ts'o
2012-04-13 0:10 ` Bug: Large writes can fail on ext4 if the write buffer is not empty Dave Chinner
2012-04-19 13:10 ` Jouko Orava
2012-04-19 14:15 ` Eric Sandeen
2012-04-19 14:38 ` Jouko Orava
2012-04-19 14:45 ` Eric Sandeen
2012-04-19 15:09 ` Jouko Orava
2012-04-19 15:28 ` Zheng Liu
2012-04-20 2:12 ` Dave Chinner [this message]
2012-04-19 14:56 ` Zheng Liu
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