linux-kernel - Re: [PATCH] tpm: add support for partial reads

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 23 Jul 2018 14:38:08 -0700
From:   Tadeusz Struk <tadeusz.struk@...el.com>
To:     James Bottomley <James.Bottomley@...senPartnership.com>,
        Jarkko Sakkinen <jarkko.sakkinen@...ux.intel.com>
Cc:     jgg@...pe.ca, linux-integrity@...r.kernel.org,
        linux-security-module@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] tpm: add support for partial reads

On 07/23/2018 02:13 PM, James Bottomley wrote:
> The current patch does, you even provided a use case in your last email
>  (it's do command to get sizing followed by do command with correctly
> sized buffer). 

The example I provided was: #1 send a command, #2 read the response header
(10 bytes), get the actual response size from the header and then #3 read
the full response (response size - size of the header bytes).

> 
> However, if you tie it to O_NONBLOCK, it won't because no-one currently
> opens the TPM device non blocking so it's an ABI conformant
> discriminator of the uses.  Tying to O_NONBLOCK should be simple
> because it's in file->f_flags.

I think that it might be an option. Especially that I have this on top of
the async patch. Let's discuss this when Jarkko is back.

Thanks,
-- 
Tadeusz