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Date: Tue, 31 Jan 2017 02:25:22 +0000 (GMT)
From: James Simmons <jsimmons@infradead.org>
To: Dan Carpenter <dan.carpenter@oracle.com>
cc: Liang Zhen <liang.zhen@intel.com>,
        Amir Shehata <amir.shehata@intel.com>,
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        Doug Oucharek <doug.s.oucharek@intel.com>
Subject: Re: [PATCH 60/60] staging: lustre: libcfs: fix minimum size check
 for libcfs ioctl
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> It looks like what happened is there were two patches applied out of
> sync.  Let's add a fixes tag and CC the original author.

So the only problem here is the commit message. I will update it then.
 
> Fixes: ed2f549dc0f6 ("staging: lustre: libcfs: test if userland data is to small")
> 
> This patch was probably correct when it was written but commit
> 1290932728e5 ("staging: lustre: Dynamic LNet Configuration (DLC) IOCTL
> changes") ended up getting applied first so the size was wrong.
> 
> The lstcon_ioctl_entry() function doesn't have enough size checking.

This sounds like a separate patch. I will open a ticket about this and
your comments below.

> Also I'm uncomfortable with:
> 
> 	data = container_of(hdr, struct libcfs_ioctl_data, ioc_hdr);
> 
> If hdr isn't the first member of the struct then the code is broken but
> container_of() implies that that isn't a hard requirement.  It should
> just be:
> 
> 	data = (struct libcfs_ioctl_data *)hdr;

Don't know if hdr being first is a hard requirment. Doug, Amir do you know 
if it is an requirement?