[tip:perf/core] perf strbuf: Match va_{add,copy} with va_end

[tip-bot for Sanskriti Sharma]

Commit-ID:  ce49d8436cffa9b7a6a5f110879d53e89dbc6746
Gitweb:     https://git.kernel.org/tip/ce49d8436cffa9b7a6a5f110879d53e89dbc6746
Author:     Sanskriti Sharma <sansharm@xxxxxxxxxx>
AuthorDate: Tue, 2 Oct 2018 10:29:10 -0400
Committer:  Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Mon, 8 Oct 2018 14:23:44 -0300

perf strbuf: Match va_{add,copy} with va_end

Ensure that all code paths in strbuf_addv() call va_end() on the
ap_saved copy that was made.

Fixes the following coverity complaint:

  Error: VARARGS (CWE-237): [#def683]
  tools/perf/util/strbuf.c:106: missing_va_end: va_end was not called
  for "ap_saved".

Signed-off-by: Sanskriti Sharma <sansharm@xxxxxxxxxx>
Reviewed-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Joe Lawrence <joe.lawrence@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/1538490554-8161-2-git-send-email-sansharm@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/util/strbuf.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/strbuf.c b/tools/perf/util/strbuf.c
index 3d1cf5bf7f18..9005fbe0780e 100644
--- a/tools/perf/util/strbuf.c
+++ b/tools/perf/util/strbuf.c
@@ -98,19 +98,25 @@ static int strbuf_addv(struct strbuf *sb, const char *fmt, va_list ap)
 
 	va_copy(ap_saved, ap);
 	len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
-	if (len < 0)
+	if (len < 0) {
+		va_end(ap_saved);
 		return len;
+	}
 	if (len > strbuf_avail(sb)) {
 		ret = strbuf_grow(sb, len);
-		if (ret)
+		if (ret) {
+			va_end(ap_saved);
 			return ret;
+		}
 		len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap_saved);
 		va_end(ap_saved);
 		if (len > strbuf_avail(sb)) {
 			pr_debug("this should not happen, your vsnprintf is broken");
+			va_end(ap_saved);
 			return -EINVAL;
 		}
 	}
+	va_end(ap_saved);
 	return strbuf_setlen(sb, sb->len + len);
 }