From 19a6ebfa895ce3baa6bd07cb5227556c82f20cb6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20G=C3=B6ttsche?= <cgzones@googlemail.com>
Date: Tue, 8 Jun 2021 17:59:01 +0200
Subject: [PATCH] libsepol: do not allocate memory of size 0
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Content-Type: text/plain; charset=UTF-8
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In case cats_ebitmap_len() returns 0, do not allocate but quit.

Found by clang-analyzer

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Acked-by: James Carter <jwcart2@gmail.com>
---
 libsepol/src/kernel_to_cil.c  | 5 ++++-
 libsepol/src/kernel_to_conf.c | 5 ++++-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/libsepol/src/kernel_to_cil.c b/libsepol/src/kernel_to_cil.c
index 30a27bf527d5..5aaee6288565 100644
--- a/libsepol/src/kernel_to_cil.c
+++ b/libsepol/src/kernel_to_cil.c
@@ -1034,11 +1034,14 @@ static char *cats_ebitmap_to_str(struct ebitmap *cats, char **val_to_name)
 {
 	struct ebitmap_node *node;
 	uint32_t i, start, range;
-	char *catsbuf, *p;
+	char *catsbuf = NULL, *p;
 	const char *fmt;
 	int len, remaining;
 
 	remaining = (int)cats_ebitmap_len(cats, val_to_name);
+	if (remaining == 0) {
+		goto exit;
+	}
 	catsbuf = malloc(remaining);
 	if (!catsbuf) {
 		goto exit;
diff --git a/libsepol/src/kernel_to_conf.c b/libsepol/src/kernel_to_conf.c
index ffdf179a71f3..cb8e13809d52 100644
--- a/libsepol/src/kernel_to_conf.c
+++ b/libsepol/src/kernel_to_conf.c
@@ -1025,12 +1025,15 @@ static char *cats_ebitmap_to_str(struct ebitmap *cats, char **val_to_name)
 {
 	struct ebitmap_node *node;
 	uint32_t i, start, range, first;
-	char *catsbuf, *p;
+	char *catsbuf = NULL, *p;
 	const char *fmt;
 	char sep;
 	int len, remaining;
 
 	remaining = (int)cats_ebitmap_len(cats, val_to_name);
+	if (remaining == 0) {
+		goto exit;
+	}
 	catsbuf = malloc(remaining);
 	if (!catsbuf) {
 		goto exit;
-- 
2.32.0