perf tools: Validate perf event header size
The 'size' variable includes the header so must be at least
'sizeof(struct perf_event_header)'. Error out immediately if that is
not the case. Also don't byte-swap the header until it is actually
"fetched" from the mmap region.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1372944040-32690-9-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 6b71b88..951a1cf 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1094,8 +1094,10 @@
perf_event_header__bswap(&event->header);
size = event->header.size;
- if (size == 0)
- size = 8;
+ if (size < sizeof(struct perf_event_header)) {
+ pr_err("bad event header size\n");
+ goto out_err;
+ }
if (size > cur_size) {
void *new = realloc(buf, size);
@@ -1164,8 +1166,12 @@
if (session->header.needs_swap)
perf_event_header__bswap(&event->header);
- if (head + event->header.size > mmap_size)
+ if (head + event->header.size > mmap_size) {
+ /* We're not fetching the event so swap back again */
+ if (session->header.needs_swap)
+ perf_event_header__bswap(&event->header);
return NULL;
+ }
return event;
}
@@ -1245,7 +1251,7 @@
size = event->header.size;
- if (size == 0 ||
+ if (size < sizeof(struct perf_event_header) ||
perf_session__process_event(session, event, tool, file_pos) < 0) {
pr_err("%#" PRIx64 " [%#x]: failed to process type: %d\n",
file_offset + head, event->header.size,