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>
This commit is contained in:
Adrian Hunter 2013-07-04 16:20:27 +03:00 committed by Arnaldo Carvalho de Melo
parent 93edcbd91d
commit 27389d7823

View File

@ -1094,8 +1094,10 @@ static int __perf_session__process_pipe_events(struct perf_session *self,
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 @@ fetch_mmaped_event(struct perf_session *session,
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 @@ int __perf_session__process_events(struct perf_session *session,
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,