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Subject: Re: [PATCH 1/4] nfs: use-after-free in svc_process_common()
To:     Trond Myklebust <trondmy@hammerspace.com>,
        "bfields@fieldses.org" <bfields@fieldses.org>
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        "chuck.lever@oracle.com" <chuck.lever@oracle.com>,
        "jlayton@kernel.org" <jlayton@kernel.org>
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From:   Vasily Averin <vvs@virtuozzo.com>
Message-ID: <226cf590-9a53-a126-cbc7-b8624c8d6102@virtuozzo.com>
Date:   Mon, 24 Dec 2018 14:48:59 +0300
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On 12/24/18 12:53 PM, Trond Myklebust wrote:
> On Mon, 2018-12-24 at 11:59 +0300, Vasily Averin wrote:
>> Can I just check rqstp->rq_prot ? It is inherited from incoming
>> svc_req,
>> and it seems it enough to check its propo, it isn't? 
>>
>> svc_process_common()
>> ...
>>         /* Setup reply header */
>>         if (rqstp->rq_prot == IPPROTO_TCP)
>>                 svc_tcp_prep_reply_hdr(rqstp);
> 
> Yes. In these days with retpoline slowing down all indirect function
> calls, then the above is probably the better solution.

I've submitted v4 patch version with these changes.