[PATCH 5/8] perf header: Use a max number of command line args

[Arnaldo Carvalho de Melo]

From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

Sashiko suggests we use some reasonable max number of args to avoid
overflows when reading perf.data files, do it.

Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/util/header.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index a3b7b796639b42c0..a18f216f77c27430 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -2795,6 +2795,9 @@ process_event_desc(struct feat_fd *ff, void *data __maybe_unused)
 	return 0;
 }
 
+// Some reasonable arbitrary max for the number of command line arguments
+#define MAX_CMDLINE_NR 32768
+
 static int process_cmdline(struct feat_fd *ff, void *data __maybe_unused)
 {
 	struct perf_env *env = &ff->ph->env;
@@ -2804,6 +2807,9 @@ static int process_cmdline(struct feat_fd *ff, void *data __maybe_unused)
 	if (do_read_u32(ff, &nr))
 		return -1;
 
+	if (nr > MAX_CMDLINE_NR)
+		return -1;
+
 	env->nr_cmdline = nr;
 
 	cmdline = zalloc(ff->size + nr + 1);
-- 
2.53.0