[PATCH] perf tools: Fix proper buffer size for feature processing

From: Jiri Olsa
Date: Mon Jul 15 2019 - 11:06:49 EST


After Song Liu's segfault fix for pipe mode, Arnaldo reported
following error:

# perf record -o - | perf script
0x514 [0x1ac]: failed to process type: 80

It's caused by wrong buffer size setup in feature processing,
which makes cpu topology feature fail, because it's using
buffer size to recognize its header version.

Cc: David Carrillo-Cisneros <davidcc@xxxxxxxxxx>
Cc: Song Liu <songliubraving@xxxxxx>
Cc: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Reported-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Fixes: e9def1b2e74e ("perf tools: Add feature header record to pipe-mode")
Link: http://lkml.kernel.org/n/tip-2lj87zz8tq9ye1ntax3ulw0n@xxxxxxxxxxxxxx
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
tools/perf/util/header.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index c24db7f4909c..20111f8da5cb 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -3747,7 +3747,7 @@ int perf_event__process_feature(struct perf_session *session,
return 0;

ff.buf = (void *)fe->data;
- ff.size = event->header.size - sizeof(event->header);
+ ff.size = event->header.size - sizeof(*fe);
ff.ph = &session->header;

if (feat_ops[feat].process(&ff, NULL))
--
2.21.0