[GIT PULL] perf tools updates

Ensure the size of the dynamic fields such as callchains
or raw events don't overlap the whole event boundaries.

This prevents from dereferencing junk if the given size of
the callchain goes too eager.

Reported-by: Linus Torvalds
Reported-by: Ingo Molnar
Signed-off-by: Frederic Weisbecker
Cc: Ingo Molnar
Cc: Peter Zijlstra
Cc: Arnaldo Carvalho de Melo
Cc: Stephane Eranian

tools/perf/util/evsel.c | 26 ++++++++++++++++++++++++++
1 files changed, 26 insertions(+), 0 deletions(-)

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index bfce8bf..ee0fe0d 100644
a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -303,6 +303,17 @@ static int perf_event__parse_id_sample(const union perf_event *event, u64 type,
return 0;
}

+static bool sample_overlap(const union perf_event *event,
+ const void *offset, u64 size)
+{
+ const void *base = event;
+
+ if (offset + size > base + event->header.size)
+ return true;
+
+ return false;
+}
+
int perf_event__parse_sample(const union perf_event *event, u64 type,
int sample_size, bool sample_id_all,
struct perf_sample *data)
@@ -373,14 +384,29 @@ int perf_event__parse_sample(const union perf_event *event, u64 type,
}

if (type & PERF_SAMPLE_CALLCHAIN) {
+ if (sample_overlap(event, array, sizeof(data->callchain->nr)))
+ return -EFAULT;
+
data->callchain = (struct ip_callchain *)array;
+
+ if (sample_overlap(event, array, data->callchain->nr))
+ return -EFAULT;
+
array += 1 + data->callchain->nr;
}

if (type & PERF_SAMPLE_RAW) {
u32 *p = (u32 *)array;
+
+ if (sample_overlap(event, array, sizeof(u32)))
+ return -EFAULT;
+
data->raw_size = *p;
p++;
+
+ if (sample_overlap(event, p, data->raw_size))
+ return -EFAULT;
+
data->raw_data = p;
}

1.7.3.2

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