From a285412479b6d5af3e48273a92ec2f1987df8cd1 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Sat, 21 May 2011 19:33:04 +0200 Subject: perf tools: Pre-check sample size before parsing Check that the total size of the sample fields having a fixed size do not exceed the one of the whole event. This robustifies the sample parsing. Signed-off-by: Frederic Weisbecker Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: Stephane Eranian --- tools/perf/builtin-test.c | 4 +++- tools/perf/util/event.c | 16 ++++++++++++++++ tools/perf/util/event.h | 12 +++++++++++- tools/perf/util/evsel.c | 6 +++++- tools/perf/util/python.c | 5 +++-- tools/perf/util/session.c | 1 + tools/perf/util/session.h | 2 ++ 7 files changed, 41 insertions(+), 5 deletions(-) (limited to 'tools') diff --git a/tools/perf/builtin-test.c b/tools/perf/builtin-test.c index 11e3c84..44d7df2 100644 --- a/tools/perf/builtin-test.c +++ b/tools/perf/builtin-test.c @@ -474,6 +474,7 @@ static int test__basic_mmap(void) unsigned int nr_events[nsyscalls], expected_nr_events[nsyscalls], i, j; struct perf_evsel *evsels[nsyscalls], *evsel; + int sample_size = perf_sample_size(attr.sample_type); for (i = 0; i < nsyscalls; ++i) { char name[64]; @@ -558,7 +559,8 @@ static int test__basic_mmap(void) goto out_munmap; } - perf_event__parse_sample(event, attr.sample_type, false, &sample); + perf_event__parse_sample(event, attr.sample_type, sample_size, + false, &sample); evsel = perf_evlist__id2evsel(evlist, sample.id); if (evsel == NULL) { pr_debug("event with id %" PRIu64 diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c index 1023f67..17c1c3c 100644 --- a/tools/perf/util/event.c +++ b/tools/perf/util/event.c @@ -35,6 +35,22 @@ const char *perf_event__name(unsigned int id) return perf_event__names[id]; } +int perf_sample_size(u64 sample_type) +{ + u64 mask = sample_type & PERF_SAMPLE_MASK; + int size = 0; + int i; + + for (i = 0; i < 64; i++) { + if ((mask << i) & 1) + size++; + } + + size *= sizeof(u64); + + return size; +} + static struct perf_sample synth_sample = { .pid = -1, .tid = -1, diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h index 9c35170..c083328 100644 --- a/tools/perf/util/event.h +++ b/tools/perf/util/event.h @@ -56,6 +56,13 @@ struct read_event { u64 id; }; + +#define PERF_SAMPLE_MASK \ + (PERF_SAMPLE_IP | PERF_SAMPLE_TID | \ + PERF_SAMPLE_TIME | PERF_SAMPLE_ADDR | \ + PERF_SAMPLE_ID | PERF_SAMPLE_STREAM_ID | \ + PERF_SAMPLE_CPU | PERF_SAMPLE_PERIOD) + struct sample_event { struct perf_event_header header; u64 array[]; @@ -75,6 +82,8 @@ struct perf_sample { struct ip_callchain *callchain; }; +int perf_sample_size(u64 sample_type); + #define BUILD_ID_SIZE 20 struct build_id_event { @@ -178,6 +187,7 @@ int perf_event__preprocess_sample(const union perf_event *self, const char *perf_event__name(unsigned int id); int perf_event__parse_sample(const union perf_event *event, u64 type, - bool sample_id_all, struct perf_sample *sample); + int sample_size, bool sample_id_all, + struct perf_sample *sample); #endif /* __PERF_RECORD_H */ diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index d6fd59b..bfce8bf 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -304,7 +304,8 @@ static int perf_event__parse_id_sample(const union perf_event *event, u64 type, } int perf_event__parse_sample(const union perf_event *event, u64 type, - bool sample_id_all, struct perf_sample *data) + int sample_size, bool sample_id_all, + struct perf_sample *data) { const u64 *array; @@ -319,6 +320,9 @@ int perf_event__parse_sample(const union perf_event *event, u64 type, array = event->sample.array; + if (sample_size + sizeof(event->header) > event->header.size) + return -EFAULT; + if (type & PERF_SAMPLE_IP) { data->ip = event->ip.ip; array++; diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c index 8b0eff8..4174c09 100644 --- a/tools/perf/util/python.c +++ b/tools/perf/util/python.c @@ -690,8 +690,9 @@ static PyObject *pyrf_evlist__read_on_cpu(struct pyrf_evlist *pevlist, return PyErr_NoMemory(); first = list_entry(evlist->entries.next, struct perf_evsel, node); - perf_event__parse_sample(event, first->attr.sample_type, sample_id_all, - &pevent->sample); + perf_event__parse_sample(event, first->attr.sample_type, + perf_sample_size(first->attr.sample_type), + sample_id_all, &pevent->sample); return pyevent; } diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c index db65206..8940fd8 100644 --- a/tools/perf/util/session.c +++ b/tools/perf/util/session.c @@ -97,6 +97,7 @@ out: void perf_session__update_sample_type(struct perf_session *self) { self->sample_type = perf_evlist__sample_type(self->evlist); + self->sample_size = perf_sample_size(self->sample_type); self->sample_id_all = perf_evlist__sample_id_all(self->evlist); perf_session__id_header_size(self); } diff --git a/tools/perf/util/session.h b/tools/perf/util/session.h index 8daaa2d..66d4e14 100644 --- a/tools/perf/util/session.h +++ b/tools/perf/util/session.h @@ -43,6 +43,7 @@ struct perf_session { */ struct hists hists; u64 sample_type; + int sample_size; int fd; bool fd_pipe; bool repipe; @@ -159,6 +160,7 @@ static inline int perf_session__parse_sample(struct perf_session *session, struct perf_sample *sample) { return perf_event__parse_sample(event, session->sample_type, + session->sample_size, session->sample_id_all, sample); } -- cgit v1.1