Messages in this thread | | | Date | Thu, 6 Oct 2011 19:14:12 +0200 | From | Andi Kleen <> | Subject | Re: [PATCH 07/12] perf_events: add LBR software filter support for Intel X86 |
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On Thu, Oct 06, 2011 at 06:43:44PM +0200, Peter Zijlstra wrote: > On Thu, 2011-10-06 at 17:32 +0200, Andi Kleen wrote: > > > + kernel_insn_init(&insn, kaddr); > > > + insn_get_opcode(&insn); > > > > This makes me uncomfortable. AFAIK that's the first use of the opcode > > decoder being used directly for user space. It has a quite large attack > > surface. Who says it cannot be exploited? > > You mean: > arch/x86/kernel/cpu/perf_event_intel_ds.c:intel_pmu_pebs_fixup_ip() > doesn't use the opcode decoder on user space code?
True it does. Ok the second. I know uprobes is planning it too, so the problem has to be handled eventually.
Still it makes me uncomfortable.
-Andi -- ak@linux.intel.com -- Speaking for myself only.
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