From 2b6f639a5209f70a6c065f57bfd4b2bf3e28dbe4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20G=C3=B6ttsche?= <cgzones@googlemail.com>
Date: Mon, 29 Apr 2024 18:39:00 +0200
Subject: [PATCH] libselinux: avoid pointer dereference before check
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Since commit 5876aca0 ("libselinux: free data on selabel open failure")
the close handler of label backends must support partial initialized
state, e.g. ->data being NULL.  Thus checks for NULL were added, but in
two cases the pointers in question were already dereferenced before.

Reorder the dereference after the NULL-checks.

Fixes: 5876aca0 ("libselinux: free data on selabel open failure")
Reported-by: Cppcheck
Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Acked-by: James Carter <jwcart2@gmail.com>
---
 src/label_media.c | 4 +++-
 src/label_x.c     | 4 +++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/label_media.c b/src/label_media.c
index 94a58062..852aeada 100644
--- a/src/label_media.c
+++ b/src/label_media.c
@@ -164,12 +164,14 @@ finish:
 static void close(struct selabel_handle *rec)
 {
 	struct saved_data *data = (struct saved_data *)rec->data;
-	struct spec *spec, *spec_arr = data->spec_arr;
+	struct spec *spec, *spec_arr;
 	unsigned int i;
 
 	if (!data)
 		return;
 
+	spec_arr = data->spec_arr;
+
 	for (i = 0; i < data->nspec; i++) {
 		spec = &spec_arr[i];
 		free(spec->key);
diff --git a/src/label_x.c b/src/label_x.c
index f994eefa..a8decc7a 100644
--- a/src/label_x.c
+++ b/src/label_x.c
@@ -191,12 +191,14 @@ finish:
 static void close(struct selabel_handle *rec)
 {
 	struct saved_data *data = (struct saved_data *)rec->data;
-	struct spec *spec, *spec_arr = data->spec_arr;
+	struct spec *spec, *spec_arr;
 	unsigned int i;
 
 	if (!data)
 		return;
 
+	spec_arr = data->spec_arr;
+
 	for (i = 0; i < data->nspec; i++) {
 		spec = &spec_arr[i];
 		free(spec->key);
-- 
2.33.0