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Issue 761078 link

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Issue metadata

Status: Untriaged
Owner: ----
Cc:
Components:
EstimatedDays: ----
NextAction: ----
OS: Chrome
Pri: 2
Type: Bug



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snow: M60: incomplete dev<->verified sequence leads to OOBE

Project Member Reported by apronin@chromium.org, Aug 31 2017

Issue description

Branched from  issue 755909 

Based on the provided video ( crbug.com/755909#c1 ), the following sequence leads to seeing OOBE on snow/M60:
1) Esc-Reload-Power to get to recover screen.
2) On recovery screen: "Ctrl-D", then "Enter" to turn OS verification OFF - leads to reboot.
3) On OS verification is OFF screen: "Space", then "Enter" to turn OS verification ON - leads to reboot.

At no point the OS has a chance to do the powerwash (stateful wipe + clearing the tpm owner), as confirmed by no evidence of the powerwash whitescreen in the video. Why does it go to OOBE? 

Differences in f/w behavior (snow-2695.90.B vs gnawty-5216.39.B)? 
 

Comment 1 by sha...@chromium.org, Aug 31 2017

At VbInit() time (before we have the opportunity to transition out of dev mode), if we just transitioned to dev mode, we're clearing TPM ownership:

        /*
         * Clear ownership if developer flag has toggled, or if an owner-clear
         * has been requested.
         */
        if ((developer_mode ? FLAG_LAST_BOOT_DEVELOPER : 0) !=
            (in_flags & FLAG_LAST_BOOT_DEVELOPER)) {
                VBDEBUG(("TPM: Developer flag changed; clearing owner.\n"));
                RETURN_ON_FAILURE(TPMClearAndReenable());
        } else if (clear_tpm_owner_request) {
                VBDEBUG(("TPM: Clearing owner as specifically requested.\n"));
                RETURN_ON_FAILURE(TPMClearAndReenable());
        }

I would expect that would put us back at OOBE on our next boot regardless of whether we get to boot a kernel in dev mode. Is it not the case for some platforms? Which platforms?
Components: OS>Systems>Security
Status: Archived (was: Untriaged)
Looks like this is WAI? Also inactive for quite some time so archiving - Andrey please re-open if necessary
Status: Untriaged (was: Archived)
I'd like to understand if that's indeed happening, and, if yes, what's the reason.

Based on info in  issue 755909 :
 - on snow running M60, going through these steps (incomplete transition to dev) leads to OOBE;
 - on gnawty running M62, it does not.

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