On 9/21/19 5:30 PM, Nicolas Iooss wrote:
Several static analyzers (clang's one, Facebook Infer, etc.) warn about
NULL pointer dereferences after a call to CU_ASSERT_PTR_NOT_NULL_FATAL()
in the test code written using CUnit framework. This is because this
CUnit macro is too complex for them to understand that the pointer
cannot be NULL: it is translated to a call to CU_assertImplementation()
with an argument as TRUE in order to mean that the call is fatal if the
asserted condition failed (cf.
http://cunit.sourceforge.net/doxdocs/group__Framework.html).
A possible solution could consist in replacing the
CU_ASSERT_..._FATAL() calls by assert() ones, as most static analyzers
know about assert(). Nevertheless this seems to go against CUnit's API.
An alternative solution consists in overriding CU_ASSERT_..._FATAL()
macros in order to expand to assert() after a call to the matching
CU_ASSERT_...() non-fatal macro. This appears to work fine and to remove
many false-positive warnings from various static analyzers.
As this substitution should only occur when using static analyzer, put
it under #ifdef __CHECKER__, which is the macro used by sparse when
analyzing the Linux kernel.
Signed-off-by: Nicolas Iooss <nicolas.iooss@xxxxxxx>
---
libsemanage/tests/test_utilities.c | 2 ++
libsemanage/tests/utilities.h | 24 ++++++++++++++++++++++
libsepol/tests/helpers.h | 27 +++++++++++++++++++++++++
libsepol/tests/test-common.c | 2 ++
libsepol/tests/test-deps.c | 2 ++
libsepol/tests/test-expander-attr-map.c | 1 +
libsepol/tests/test-expander-roles.c | 1 +
libsepol/tests/test-expander-users.c | 1 +
scripts/run-scan-build | 6 +++++-
9 files changed, 65 insertions(+), 1 deletion(-)
diff --git a/libsemanage/tests/test_utilities.c b/libsemanage/tests/test_utilities.c
index 601508c2c386..ba995b5ae094 100644
--- a/libsemanage/tests/test_utilities.c
+++ b/libsemanage/tests/test_utilities.c
@@ -34,6 +34,8 @@
#include <string.h>
#include <unistd.h>
+#include "utilities.h"
+
void test_semanage_is_prefix(void);
void test_semanage_split_on_space(void);
void test_semanage_split(void);
diff --git a/libsemanage/tests/utilities.h b/libsemanage/tests/utilities.h
index c9d54d1e1b76..1d15a98d9db1 100644
--- a/libsemanage/tests/utilities.h
+++ b/libsemanage/tests/utilities.h
@@ -41,6 +41,30 @@
CU_ASSERT_STRING_EQUAL(__str, __str2); \
} while (0)
+
+/* Override CU_*_FATAL() in order to help static analyzers by really asserting that an assertion holds */
+#ifdef __CHECKER__
+
+#undef CU_ASSERT_FATAL
+#define CU_ASSERT_FATAL(value) do { \
+ CU_ASSERT(value); \
+ assert(value); \
+ } while (0)
You only want to evaluate value once and save the result for use in both
CU_ASSERT() and assert() or it could change, e.g.
CU_ASSERT_FATAL(semanage_ibendport_del_local(sh, key) >= 0);
+
+#undef CU_FAIL_FATAL
+#define CU_FAIL_FATAL(msg) do { \
+ CU_FAIL(msg); \
+ assert(0); \
+ } while (0)
+
+#undef CU_ASSERT_PTR_NOT_NULL_FATAL
+#define CU_ASSERT_PTR_NOT_NULL_FATAL(value) do { \
+ CU_ASSERT_PTR_NOT_NULL(value); \
+ assert((value) != NULL); \
+ } while (0)
Ditto.
+
+#endif /* __CHECKER__ */
+
#define I_NULL -1
#define I_FIRST 0
#define I_SECOND 1
diff --git a/libsepol/tests/helpers.h b/libsepol/tests/helpers.h
index 10d390946499..34b8f21e10e0 100644
--- a/libsepol/tests/helpers.h
+++ b/libsepol/tests/helpers.h
@@ -24,9 +24,36 @@
#include <sepol/policydb/policydb.h>
#include <sepol/policydb/conditional.h>
+#include <CUnit/Basic.h>
/* helper functions */
+/* Override CU_*_FATAL() in order to help static analyzers by really asserting that an assertion holds */
+#ifdef __CHECKER__
+
+#include <assert.h>
+
+#undef CU_ASSERT_FATAL
+#define CU_ASSERT_FATAL(value) do { \
+ CU_ASSERT(value); \
+ assert(value); \
+ } while (0)
+
+#undef CU_FAIL_FATAL
+#define CU_FAIL_FATAL(msg) do { \
+ CU_FAIL(msg); \
+ assert(0); \
+ } while (0)
+
+#undef CU_ASSERT_PTR_NOT_NULL_FATAL
+#define CU_ASSERT_PTR_NOT_NULL_FATAL(value) do { \
+ CU_ASSERT_PTR_NOT_NULL(value); \
+ assert((value) != NULL); \
+ } while (0)
+
+#endif /* __CHECKER__ */
+
+
/* Load a source policy into p. policydb_init will called within this function.
*
* Example: test_load_policy(p, POLICY_BASE, 1, "foo", "base.conf") will load the
diff --git a/libsepol/tests/test-common.c b/libsepol/tests/test-common.c
index 1d902880fe2e..f690635eee27 100644
--- a/libsepol/tests/test-common.c
+++ b/libsepol/tests/test-common.c
@@ -26,6 +26,8 @@
#include <CUnit/Basic.h>
+#include "helpers.h"
+
void test_sym_presence(policydb_t * p, const char *id, int sym_type, unsigned int scope_type, unsigned int *decls, unsigned int len)
{
scope_datum_t *scope;
diff --git a/libsepol/tests/test-deps.c b/libsepol/tests/test-deps.c
index 6bbba810564a..f4ab09ba0dbf 100644
--- a/libsepol/tests/test-deps.c
+++ b/libsepol/tests/test-deps.c
@@ -66,6 +66,8 @@
#include <sepol/debug.h>
#include <sepol/handle.h>
+#include "helpers.h"
+
#define BASE_MODREQ_TYPE_GLOBAL 0
#define BASE_MODREQ_ATTR_GLOBAL 1
#define BASE_MODREQ_OBJ_GLOBAL 2
diff --git a/libsepol/tests/test-expander-attr-map.c b/libsepol/tests/test-expander-attr-map.c
index d10636ca09a8..a9744541fe00 100644
--- a/libsepol/tests/test-expander-attr-map.c
+++ b/libsepol/tests/test-expander-attr-map.c
@@ -21,6 +21,7 @@
#include "test-expander-attr-map.h"
#include "test-common.h"
+#include "helpers.h"
#include <sepol/policydb/policydb.h>
#include <CUnit/Basic.h>
diff --git a/libsepol/tests/test-expander-roles.c b/libsepol/tests/test-expander-roles.c
index aba3c9bd19c4..74c781b85e68 100644
--- a/libsepol/tests/test-expander-roles.c
+++ b/libsepol/tests/test-expander-roles.c
@@ -22,6 +22,7 @@
#include "test-expander-roles.h"
#include "test-common.h"
+#include "helpers.h"
#include <sepol/policydb/policydb.h>
#include <CUnit/Basic.h>
diff --git a/libsepol/tests/test-expander-users.c b/libsepol/tests/test-expander-users.c
index 9d9c7a62f215..ab2265c110d5 100644
--- a/libsepol/tests/test-expander-users.c
+++ b/libsepol/tests/test-expander-users.c
@@ -21,6 +21,7 @@
*/
#include "test-expander-users.h"
+#include "helpers.h"
#include <sepol/policydb/policydb.h>
#include <CUnit/Basic.h>
diff --git a/scripts/run-scan-build b/scripts/run-scan-build
index 88fe551ce698..ae5aa48b4a05 100755
--- a/scripts/run-scan-build
+++ b/scripts/run-scan-build
@@ -22,7 +22,11 @@ export RUBYLIB="$DESTDIR/$(${RUBY:-ruby} -e 'puts RbConfig::CONFIG["vendorlibdir
# Build and analyze
make -C .. CC=clang clean distclean -j"$(nproc)"
-scan-build -analyze-headers -o "$OUTPUTDIR" make -C .. CC=clang DESTDIR="$DESTDIR" install install-pywrap install-rubywrap all test
+scan-build -analyze-headers -o "$OUTPUTDIR" make -C .. \
+ CC=clang \
+ DESTDIR="$DESTDIR" \
+ CFLAGS="-O2 -Wall -D__CHECKER__ -I$DESTDIR/usr/include" \
+ install install-pywrap install-rubywrap all test
# Reduce the verbosity in order to keep the message from scan-build saying
# "scan-build: Run 'scan-view /.../output-scan-build/2018-...' to examine bug reports.
