Messages in this thread | | | Date | Fri, 15 May 2009 21:56:44 +0200 | From | Pavel Machek <> | Subject | Re: [RFC 1/1] seccomp: Add bitmask of allowed system calls. |
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Hi!
> Briefly, it adds a second seccomp mode (2) where one uploads a bitmask. > Syscall n is allowed if, and only if, bit n is true in the bitmask. If n > is beyond the range of the bitmask, the syscall is denied. > > If prctl is allowed by the bitmask, then a process may switch to mode 1, > or may set a new bitmask iff the new bitmask is a subset of the current > one. (Possibly moving to mode 1 should only be allowed if read, write, > sigreturn, exit are in the currently allowed set.) > > If a process forks/clones, the child inherits the seccomp state of the > parent. (And hopefully I'm managing the memory correctly here.)
If you allow setuid exec here, you have added a security hole. Deny setuid() to sendmail and have fun...
-- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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