Messages in this thread | | | Subject | Re: [PATCH 07/12] perf_events: add LBR software filter support for Intel X86 | From | Peter Zijlstra <> | Date | Thu, 06 Oct 2011 18:43:44 +0200 |
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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?
ISTR Masami telling me they ran fuzzers on it, feeding it bad instructions etc. But maybe he can tell more.
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