Messages in this thread | | | Date | Wed, 6 Jun 2012 10:54:59 +0930 | From | Christopher Yeoh <> | Subject | Re: [PATCH] CMA: Do no enable it by default |
| |
On Tue, 5 Jun 2012 13:05:41 +0200 Borislav Petkov <bp@amd64.org> wrote: > > CROSS_MEMORY_ATTACH is a MPI feature which shouldn't be enabled by > default on every linux system simply because the majority of users do > not need it.
btw although CMA was primarily written for MPI it is used by more than just MPI implementations. For example, recent versions of strace now use it instead of PTRACE_PEEKDATA if its available:
http://article.gmane.org/gmane.comp.sysutils.strace.devel/2467/match=process_vm_readv
> Besides, in the config option it says "... which allow a process with > the correct privileges to directly read from or write to to another > process's address space.", which, if the reading process has somehow > gained privileges (as that never happens) is your security issue right > there.
The privileges required are exactly the same as required to ptrace the target. You're rather stuffed anyway if you have a hostile process with those privileges.
Regards,
Chris -- cyeoh@au.ibm.com
| |