[tip:perf/urgent] perf bpf: Return NULL when RB tree lookup fails in perf_env__find_btf()

[tip-bot for Jiri Olsa]

Commit-ID:  2db7b1e0bd49d2b0e7d16949e167b1cfaf5c07cf
Gitweb:     https://git.kernel.org/tip/2db7b1e0bd49d2b0e7d16949e167b1cfaf5c07cf
Author:     Jiri Olsa <jolsa@xxxxxxxxxx>
AuthorDate: Wed, 17 Apr 2019 16:55:39 +0200
Committer:  Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Wed, 17 Apr 2019 14:30:23 -0300

perf bpf: Return NULL when RB tree lookup fails in perf_env__find_btf()

We don't return NULL when we don't find the bpf_prog_info_node, fix
that.

Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Reported-by: Song Liu <songliubraving@xxxxxx>
Acked-by: Song Liu <songliubraving@xxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Fixes: 3792cb2ff43b ("perf bpf: Save BTF in a rbtree in perf_env")
Link: http://lkml.kernel.org/r/20190417145539.11669-1-jolsa@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/util/env.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c
index 34a363f2e71b..9494f9dc61ec 100644
--- a/tools/perf/util/env.c
+++ b/tools/perf/util/env.c
@@ -111,10 +111,12 @@ struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id)
 		else if (btf_id > node->id)
 			n = n->rb_right;
 		else
-			break;
+			goto out;
 	}
+	node = NULL;
 
 	up_read(&env->bpf_progs.lock);
+out:
 	return node;
 }