shim: Allow data after the end of device path node in load options #694
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When looking for load option optional data, the parser asserts that the byte after the end of device path node is the same as what the file path length says it should be. While unusual, it is valid if the end of device path node comes before the end of the file path list. That supports some unusual Dell load options where there are two device paths in the list but the first is terminated by an End Entire Device Path. Maybe they intended to use an End Device Path Instance node there? Who knows. Either way, treating it as invalid ends up trying to read paths from the beginning of the option with obviously poor results. Fixes: rhboot#649 Signed-off-by: Dan Nicholson <dbn@endlessos.org>
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When looking for load option optional data, the parser asserts that the byte after the end of device path node is the same as what the file path length says it should be. While unusual, it is valid if the end of device path node comes before the end of the file path list.
That supports some unusual Dell load options where there are two device paths in the list but the first is terminated by an End Entire Device Path. Maybe they intended to use an End Device Path Instance node there? Who knows. Either way, treating it as invalid ends up trying to read paths from the beginning of the option with obviously poor results.
Fixes: #649