#12695 LOW 13.2.0: an empty SN tag prevents boot

[Zarro Boogs per Child]

#12695: an empty SN tag prevents boot
-------------------------------------------+--------------------------------
           Reporter:  Quozl                |       Owner:  Quozl               
               Type:  defect               |      Status:  new                 
           Priority:  low                  |   Milestone:  13.2.0              
          Component:  ofw - open firmware  |     Version:  Development firmware
         Resolution:                       |    Keywords:                      
        Next_action:  package              |    Verified:  0                   
Deployment_affected:                       |   Blockedby:                      
           Blocking:                       |  
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Changes (by Quozl):

  * priority:  normal => low
  * next_action:  reproduce => package


Comment:

 Reproducer:
 {{{
 d# 20 buffer: sn-buf
 : sn$  ( -- adr len )  sn-buf count ;
 : info-inject  ( -- )
    get-mfg-data  " SN" ($delete-tag)  sn$ " SN" put-ascii-tag
    flash-write-enable (put-mfg-data) no-kbc-reboot kbc-on
 ;
 info-inject
 }}}

 This inserted an SN tag with a length of zero, with no trailing NUL.

 During boot the length is unconditionally decremented to remove an
 expected trailing NUL.  The decrement wraps, and so a device tree property
 string is allocated taking all remaining dictionary space.

 Fixed in [http://tracker.coreboot.org/trac/openfirmware/changeset/3667 svn
 3667] by checking for a NUL before removing it.

 This issue is not considered likely enough to require a new release of
 Open Firmware for 13.2.0 but can be included if a new release is made for
 another reason.

-- 
Ticket URL: <http://dev.laptop.org/ticket/12695#comment:1>
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