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Subject: Re: [PATCH][V2] RDMA/nes: do not leak uninitialized resp.reserved to
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To: Chien Tin Tung <chien.tin.tung@intel.com>
References: <20170904133705.3980-1-colin.king@canonical.com>
 <20170905144041.GA13068@ctung-MOBL3.amr.corp.intel.com>
Cc: Faisal Latif <faisal.latif@intel.com>,
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From: Colin Ian King <colin.king@canonical.com>
Message-ID: <d999c3dc-6d24-84eb-0321-e5f97f3e7088@canonical.com>
Date: Tue, 5 Sep 2017 15:45:09 +0100
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On 05/09/17 15:40, Chien Tin Tung wrote:
> On Mon, Sep 04, 2017 at 02:37:05PM +0100, Colin King wrote:
>> From: Colin Ian King <colin.king@canonical.com>
>>
>> resp.reserved has not been initialized and so the copy_to_user (via
>> ib_copy_to_udata) is copying uninitialized data from the stack back
>> to user space which is a potential information leak. Fix this by
>> initializing all of resp to zero.
> 
> Reserved field is not copied as the length of reserved is subtracted
> from the size of resp and passed to ib_copy_to_udata.
> 
>  if (ib_copy_to_udata(udata, &resp, sizeof resp - sizeof resp.reserved)) {
> 
> 
> This patch is not necessary.

Apologies, I completely overlooked that.

> 
> Chien
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