From: Arnaldo Carvalho de Melo <acme@redhat.com>
Date: Wed, 19 May 2021 16:50:31 +0000 (-0300)
Subject: perf parse-events: Check if the software events array slots are populated
X-Git-Tag: microblaze-v5.15~346^2~9
X-Git-Url: http://git.monstr.eu/?p=linux-2.6-microblaze.git;a=commitdiff_plain;h=3b2f17ad1770e51b8b4e68b5069c4f1ee477eff8

perf parse-events: Check if the software events array slots are populated

To avoid a NULL pointer dereference when the kernel supports the new
feature but the tooling still hasn't an entry for it.

This happened with the recently added PERF_COUNT_SW_CGROUP_SWITCHES
software event.

Reported-by: Thomas Richter <tmricht@linux.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Link: https://lore.kernel.org/linux-perf-users/YKVESEKRjKtILhog@kernel.org/
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 269997066f6e..84108c17f48d 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -2932,9 +2932,14 @@ restart:
 	}
 
 	for (i = 0; i < max; i++, syms++) {
+		/*
+		 * New attr.config still not supported here, the latest
+		 * example was PERF_COUNT_SW_CGROUP_SWITCHES
+		 */
+		if (syms->symbol == NULL)
+			continue;
 
-		if (event_glob != NULL && syms->symbol != NULL &&
-		    !(strglobmatch(syms->symbol, event_glob) ||
+		if (event_glob != NULL && !(strglobmatch(syms->symbol, event_glob) ||
 		      (syms->alias && strglobmatch(syms->alias, event_glob))))
 			continue;