Re: Something amiss in bacula-9.6.7: Possible race condition

Hello Martin,

Very good detective work, this subtle issue was causing concurrent
database access even if the batch mode was disabled. I have pushed the
patch into the Branch-9.6 git repository.

Best Regards,
Eric

> What is the output of "show catalog" in bconsole?  My guess is that you will
> see db_driver=MySQ i.e. missing the final "L" of MySQL.  This will prevent it
> from reusing the BDB object, leading to unexpected concurrency.
> 
> The bug is caused by this change:
> 
> diff --git a/bacula/src/dird/dird.c b/bacula/src/dird/dird.c
> index fdb1d97bf9..11c4406ea7 100644
> --- a/bacula/src/dird/dird.c
> +++ b/bacula/src/dird/dird.c
> @@ -1265,7 +1265,7 @@ static bool check_catalog(cat_op mode)
>             /* To copy dbdriver field into "CAT" catalog resource class (local)
>              * from dbdriver in "BDB" catalog DB Interface class (global)
>              */
> -            strncpy(catalog->db_driver, BDB_db_driver, db_driver_len);
> +            bstrncpy(catalog->db_driver, BDB_db_driver, db_driver_len);
>           }
>        }
> 
> which was part of 9.6.4.
> 
> To fix it, replace db_driver_len with db_driver_len+1 in this call to
> bstrncpy.  This has been fixed in Bacula 11 because the seemingly minor
> problem with "status catalog" was reported in
> https://bugs.bacula.org/view.php?id=2551 but it looks like the significance of
> it wasn't realized.
>