[OSy] Windows Syscall API

[Petr Tuma]

Dobry den,

na prednasce byl vznesen dotaz na detaily kolem osetrovani chybnych
parametru ve Windows Syscall API. Zminoval jsem clanek z
www.sysinternals.com, tady je link:

http://www.sysinternals.com/Information/NativeApi.html

Konkretne z tohoto clanku: "Each system service performs operations
specific to the API they implement, of course, but most of them must
deal with the validation of the parameters passed to them from user
mode. Many parameters are pointers, and dereferencing an invalid pointer
in kernel mode without taking precautionary measures can prove
catastrophic. Validating parameters is straight-forward, but the number
of Native APIs and the number of parameters they take have made getting
it right tough for Microsoft. In 1997 I wrote a program called NTCrash
that barraged the Native API interface with garbage parameters. The
program discovered 13 WIN32K system services that failed to perform
comprehensive parameter validation, the result of which were Blue
Screens. Microsoft closed these holes in Service Pack 1."

Petr Tuma

-- 
Petr Tuma
Distributed Systems Research Group
Department of Software Engineering
Faculty of Mathematics and Physics
Charles University, Czech Republic
http://nenya.ms.mff.cuni.cz/~ceres