Posted Aug 19, 2010 14:33 UTC (Thu) by NAR
In reply to: Xorg flaw
Parent article: An ancient kernel hole is closed
Looks like any X client can crash the server, with or without a patched kernel.
If I understood correctly the problem (which is far from certain) the client can ask the server to allocate memory in the server's address space. Consequently the X server can run out of memory and the OOM killer can kill it. This seems to a be a feature, not a bug (i.e. the whole X server was designed this way). By the way, the X server uses the most memory on my system currently (according to top) and as far as I know, most of the memory is allocated on behalf of clients.
Anyway, nowadays most X clients run locally and if a malicious attacker already controls a client locally, even if it doesn't find any local root holes (which I'm sure there are plenty of), he can delete all of the user's files, send e-mails in the user's name, etc.
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