[PATCH bpf-next v3 11/11] selftests/bpf: Add verifier tests for bpf lsm

[Xu Kuohai]

From: Xu Kuohai <xukuohai at huawei.com>

Add verifier tests to check bpf lsm return values and disabled hooks.

Signed-off-by: Xu Kuohai <xukuohai at huawei.com>
---
 .../selftests/bpf/prog_tests/verifier.c       |   3 +-
 .../selftests/bpf/progs/verifier_lsm.c        | 155 ++++++++++++++++++
 2 files changed, 157 insertions(+), 1 deletion(-)
 create mode 100644 tools/testing/selftests/bpf/progs/verifier_lsm.c

diff --git a/tools/testing/selftests/bpf/prog_tests/verifier.c b/tools/testing/selftests/bpf/prog_tests/verifier.c
index c4f9f306646e..07398846085c 100644
--- a/tools/testing/selftests/bpf/prog_tests/verifier.c
+++ b/tools/testing/selftests/bpf/prog_tests/verifier.c
@@ -84,6 +84,7 @@
 #include "verifier_xadd.skel.h"
 #include "verifier_xdp.skel.h"
 #include "verifier_xdp_direct_packet_access.skel.h"
+#include "verifier_lsm.skel.h"
 
 #define MAX_ENTRIES 11
 
@@ -196,8 +197,8 @@ void test_verifier_value_illegal_alu(void)    { RUN(verifier_value_illegal_alu);
 void test_verifier_value_or_null(void)        { RUN(verifier_value_or_null); }
 void test_verifier_var_off(void)              { RUN(verifier_var_off); }
 void test_verifier_xadd(void)                 { RUN(verifier_xadd); }
-void test_verifier_xdp(void)                  { RUN(verifier_xdp); }
 void test_verifier_xdp_direct_packet_access(void) { RUN(verifier_xdp_direct_packet_access); }
+void test_verifier_lsm(void)                  { RUN(verifier_lsm); }
 
 static int init_test_val_map(struct bpf_object *obj, char *map_name)
 {
diff --git a/tools/testing/selftests/bpf/progs/verifier_lsm.c b/tools/testing/selftests/bpf/progs/verifier_lsm.c
new file mode 100644
index 000000000000..005f28eebf71
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/verifier_lsm.c
@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_misc.h"
+
+SEC("lsm/file_alloc_security")
+__description("lsm bpf prog exit with valid return code. test 1")
+__success
+__naked int return_code_vaild_test1(void)
+{
+	asm volatile ("					\
+	r0 = 0;						\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("lsm/file_alloc_security")
+__description("lsm bpf prog exit with valid return code. test 2")
+__success
+__naked int return_code_vaild_test2(void)
+{
+	asm volatile ("					\
+	r0 = -4095;					\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("lsm/file_alloc_security")
+__description("lsm bpf prog exit with valid return code. test 3")
+__success
+__naked int return_code_vaild_test3(void)
+{
+	asm volatile ("                                 \
+	call %[bpf_get_prandom_u32];                    \
+	r0 <<= 63;                                      \
+	r0 s>>= 63;                                     \
+	r0 &= -13;                                      \
+	exit;                                           \
+	"      :
+	: __imm(bpf_get_prandom_u32)
+	: __clobber_all);
+}
+
+SEC("lsm/vm_enough_memory")
+__description("lsm bpf prog exit with valid return code. test 4")
+__success
+__naked int return_code_vaild_test4(void)
+{
+	asm volatile ("					\
+	r0 = 0;						\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("lsm/vm_enough_memory")
+__description("lsm bpf prog exit with valid return code. test 5")
+__success
+__naked int return_code_vaild_test5(void)
+{
+	asm volatile ("					\
+	r0 = -4096;					\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("lsm/vm_enough_memory")
+__description("lsm bpf prog exit with valid return code. test 6")
+__success
+__naked int return_code_vaild_test6(void)
+{
+	asm volatile ("					\
+	r0 = 4096;					\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("lsm/file_free_security")
+__description("lsm bpf prog exit with valid return code. test 7")
+__success
+__naked void return_code_vaild_test7(void)
+{
+	asm volatile ("					\
+	r0 = -4096;					\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("lsm/file_free_security")
+__description("lsm bpf prog exit with valid return code. test 8")
+__success
+__naked void return_code_vaild_test8(void)
+{
+	asm volatile ("					\
+	r0 = 4096;					\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("lsm/file_alloc_security")
+__description("lsm bpf prog exit with invalid return code. test 1")
+__failure __msg("R0 has smin=1 smax=1 should have been in [-4095, 0]")
+__naked int return_code_invalid_test1(void)
+{
+	asm volatile ("					\
+	r0 = 1;						\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("lsm/file_alloc_security")
+__description("lsm bpf prog exit with invalid return code. test 2")
+__failure __msg("R0 has smin=-4096 smax=-4096 should have been in [-4095, 0]")
+__naked int return_code_invalid_test2(void)
+{
+	asm volatile ("					\
+	r0 = -4096;					\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("lsm/getprocattr")
+__description("lsm disabled hook: getprocattr")
+__failure __msg("points to disabled bpf lsm hook")
+__naked int disabled_hook_test1(void)
+{
+	asm volatile ("					\
+	r0 = 0;						\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("lsm/setprocattr")
+__description("lsm disabled hook: setprocattr")
+__failure __msg("points to disabled bpf lsm hook")
+__naked int disabled_hook_test2(void)
+{
+	asm volatile ("					\
+	r0 = 0;						\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("lsm/ismaclabel")
+__description("lsm disabled hook: ismaclabel")
+__failure __msg("points to disabled bpf lsm hook")
+__naked int disabled_hook_test3(void)
+{
+	asm volatile ("					\
+	r0 = 0;						\
+	exit;						\
+"	::: __clobber_all);
+}
+
+char _license[] SEC("license") = "GPL";
-- 
2.30.2