Re: [PATCH 1/2] metadump: warn about corruption if log is dirty

[Eric Sandeen <sandeen@sandeen.net>]

On 4/11/17 1:30 PM, Brian Foster wrote:
> On Tue, Apr 11, 2017 at 04:12:36PM +0200, Jan Tulak wrote:
>> Add a warning about possible corruption when exporting a dirty log, as
>> the log content does not agree with obfuscated metadata.
>>
>> Signed-off-by: Jan Tulak <jtulak@redhat.com>
>> ---
> 
> Thanks for posting this...
> 
>>  db/metadump.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/db/metadump.c b/db/metadump.c
>> index 66952f6..74e24b2 100644
>> --- a/db/metadump.c
>> +++ b/db/metadump.c
>> @@ -2726,7 +2726,8 @@ copy_log(void)
>>  		/* keep the dirty log */
>>  		if (obfuscate)
>>  			print_warning(
>> -_("Filesystem log is dirty; image will contain unobfuscated metadata in log."));
>> +_("Filesystem log is dirty; image will contain unobfuscated metadata in log "
>> +  "and a log replay can cause a corruption."));
> 
> I think a slightly more verbose message might be a good idea. For
> example, something like the following:
> 
> "Filesystem log is dirty; image will contain unobfuscated metadata in
> the log. Log recovery of an obfuscated image can cause filesystem
> corruption. Please mount the source image to clean the log or disable
> metadump obfuscation."
> 
> That could also say "... or verify that log recovery of the resulting
> image does not cause corruption," but that might be overkill. Thoughts?
> Eric?

I think we do need a good explanation, but that will take a lot of workd.
We could also refer to the man page for more details - it's getting pretty
long for a warning from the tool.

The other bummer is that we cannot detect whether an image has been
obfuscated, so the restore tool can only say "if it's obfuscated...."

-Eric

> Brian
> 
>>  		break;
>>  	case -1:
>>  		/* log detection error */
>> -- 
>> 2.1.4
>>
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