Messages in this thread |  | | | Date | Wed, 18 Jan 2012 02:50:13 +0100 | | From | Andi Kleen <> | | Subject | Re: Compat 32-bit syscall entry from 64-bit task!? [was: Re: [RFC,PATCH 1/2] seccomp_filters: system call filtering using BPF] |
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> Our ptrace jailer is checking cs to figure out if a task is a compat task > or not, if the kernel can change that behind our back it means our jailer
Every user program change it behind your back.
Your ptrace jailer isn't.
> I think this behaviour is so unexpected that it can only cause security > problems in the long run. Is anyone counting on this? Where is this > behaviour documented?
Look up far jumps in any x86 manual.
-Andi -- ak@linux.intel.com -- Speaking for myself only.
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