From 98cf9c4f57679bc00e5570f7bc8d373b641cd0d1 Mon Sep 17 00:00:00 2001 From: Stephane Eranian Date: Tue, 21 May 2013 12:53:37 +0200 Subject: [PATCH] perf/x86: Check branch sampling priv level in generic code This patch moves commit 194bb12 to the generic code: perf/x86/intel/lbr: Demand proper privileges for PERF_SAMPLE_BRANCH_KERNEL The check is now implemented in generic code instead of x86 specific code. That way we do not have to repeat the test in each arch supporting branch sampling. Signed-off-by: Stephane Eranian Signed-off-by: Peter Zijlstra Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Arnaldo Carvalho de Melo Link: http://lkml.kernel.org/r/20130521105337.GA2879@quad Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/perf_event_intel_lbr.c | 13 +++---------- kernel/events/core.c | 9 ++++----- 2 files changed, 7 insertions(+), 15 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event_intel_lbr.c b/arch/x86/kernel/cpu/perf_event_intel_lbr.c index d978353c939bb..de341d4ec92a4 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_lbr.c +++ b/arch/x86/kernel/cpu/perf_event_intel_lbr.c @@ -310,7 +310,7 @@ void intel_pmu_lbr_read(void) * - in case there is no HW filter * - in case the HW filter has errata or limitations */ -static int intel_pmu_setup_sw_lbr_filter(struct perf_event *event) +static void intel_pmu_setup_sw_lbr_filter(struct perf_event *event) { u64 br_type = event->attr.branch_sample_type; int mask = 0; @@ -318,11 +318,8 @@ static int intel_pmu_setup_sw_lbr_filter(struct perf_event *event) if (br_type & PERF_SAMPLE_BRANCH_USER) mask |= X86_BR_USER; - if (br_type & PERF_SAMPLE_BRANCH_KERNEL) { - if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) - return -EACCES; + if (br_type & PERF_SAMPLE_BRANCH_KERNEL) mask |= X86_BR_KERNEL; - } /* we ignore BRANCH_HV here */ @@ -342,8 +339,6 @@ static int intel_pmu_setup_sw_lbr_filter(struct perf_event *event) * be used by fixup code for some CPU */ event->hw.branch_reg.reg = mask; - - return 0; } /* @@ -391,9 +386,7 @@ int intel_pmu_setup_lbr_filter(struct perf_event *event) /* * setup SW LBR filter */ - ret = intel_pmu_setup_sw_lbr_filter(event); - if (ret) - return ret; + intel_pmu_setup_sw_lbr_filter(event); /* * setup HW LBR filter, if any diff --git a/kernel/events/core.c b/kernel/events/core.c index 53d1b300116a4..a0780b3a3d505 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -6481,11 +6481,6 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr, if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) return -EINVAL; - /* kernel level capture: check permissions */ - if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) - && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) - return -EACCES; - /* propagate priv level, when not set for branch */ if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { @@ -6503,6 +6498,10 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr, */ attr->branch_sample_type = mask; } + /* kernel level capture: check permissions */ + if ((mask & PERF_SAMPLE_BRANCH_KERNEL) + && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) + return -EACCES; } if (attr->sample_type & PERF_SAMPLE_REGS_USER) { -- 2.39.5