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Subject: Re: [patch] copy_to_user check and whitespace cleanups in
	fs/cifs/file.c
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Jesper Juhl <juhl-lkml@dif.dk>
Cc: Steve French <sfrench@samba.org>, Steve French <sfrench@us.ibm.com>,
       samba-technical <samba-technical@lists.samba.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Date: Sun, 26 Dec 2004 23:38:07 +0000
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On Sul, 2004-12-26 at 23:24, Jesper Juhl wrote:
> Hi,
> 
> Patch below adds a check for the copy_to_user return value and makes a few 
> whitespace cleanups in  fs/cifs/file.c::cifs_user_read()
> I hope bundling two different things together in one patch is OK when the 
> change is as small as this, but if you want it spplit in two patches, then 
> just say so.

Corrupts the stats
Fails to free smb_read_data where in some cases it was freed before

I'm not sure the stats matter but I think you need something more like


residue = copy_to_user(....)
if(smb_read_data) {
   cifs_buf_release(...)
  ...
}

Then

if(residue) {
    total_read += bytes_read - residue;
    FreeXid(xid);
    return total_read ? total_read: -EFAULT;
}