[bpf-next,2/7] selftests/bpf: Add tests for non-constant cond_op NE/EQ bound deduction

Commit Message

Yonghong Song March 30, 2023, 5:56 a.m. UTC

Add various tests for code pattern '<non-const> NE/EQ <const>' implemented
in the previous verifier patch. Without the verifier patch, these new
tests will fail.

Signed-off-by: Yonghong Song <[e-mail]>
---
 .../selftests/bpf/prog_tests/verifier.c       |  2 +
 .../verifier_bounds_deduction_non_const.c     | 93 +++++++++++++++++++
 2 files changed, 95 insertions(+)
 create mode 100644 tools/testing/selftests/bpf/progs/verifier_bounds_deduction_non_const.c

Patch

diff --git a/tools/testing/selftests/bpf/prog_tests/verifier.c b/tools/testing/selftests/bpf/prog_tests/verifier.c
index efc8cf2e18d0..73dff693d411 100644
--- a/tools/testing/selftests/bpf/prog_tests/verifier.c
+++ b/tools/testing/selftests/bpf/prog_tests/verifier.c
@@ -7,6 +7,7 @@ 
 #include "verifier_array_access.skel.h"
 #include "verifier_basic_stack.skel.h"
 #include "verifier_bounds_deduction.skel.h"
+#include "verifier_bounds_deduction_non_const.skel.h"
 #include "verifier_bounds_mix_sign_unsign.skel.h"
 #include "verifier_cfg.skel.h"
 #include "verifier_cgroup_inv_retcode.skel.h"
@@ -70,6 +71,7 @@  void test_verifier_and(void)                  { RUN(verifier_and); }
 void test_verifier_array_access(void)         { RUN(verifier_array_access); }
 void test_verifier_basic_stack(void)          { RUN(verifier_basic_stack); }
 void test_verifier_bounds_deduction(void)     { RUN(verifier_bounds_deduction); }
+void test_verifier_bounds_deduction_non_const(void)     { RUN(verifier_bounds_deduction_non_const); }
 void test_verifier_bounds_mix_sign_unsign(void) { RUN(verifier_bounds_mix_sign_unsign); }
 void test_verifier_cfg(void)                  { RUN(verifier_cfg); }
 void test_verifier_cgroup_inv_retcode(void)   { RUN(verifier_cgroup_inv_retcode); }
diff --git a/tools/testing/selftests/bpf/progs/verifier_bounds_deduction_non_const.c b/tools/testing/selftests/bpf/progs/verifier_bounds_deduction_non_const.c
new file mode 100644
index 000000000000..c07af47c489e
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/verifier_bounds_deduction_non_const.c
@@ -0,0 +1,93 @@ 
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_misc.h"
+
+SEC("socket")
+__description("check deducing bounds from non-const, jmp64, <non_const> == <const>")
+__success __retval(0)
+__naked void deducing_bounds_from_non_const_1(void)
+{
+	asm volatile ("					\
+	call %[bpf_ktime_get_ns];			\
+	if r0 < 3 goto l0_%=;				\
+	r2 = 2;						\
+	if r0 == r2 goto l1_%=;				\
+l0_%=:							\
+	r0 = 0;						\
+	exit;						\
+l1_%=:							\
+	r0 -= r1;					\
+	exit;						\
+"	:
+	: __imm(bpf_ktime_get_ns)
+	: __clobber_all);
+}
+
+SEC("socket")
+__description("check deducing bounds from non-const, jmp64, <non_const> != <const>")
+__success __retval(0)
+__naked void deducing_bounds_from_non_const_2(void)
+{
+	asm volatile ("					\
+	call %[bpf_ktime_get_ns];			\
+	if r0 < 3 goto l0_%=;				\
+	r2 = 2;						\
+	if r0 != r2 goto l0_%=;				\
+	goto l1_%=;					\
+l0_%=:							\
+	r0 = 0;						\
+	exit;						\
+l1_%=:							\
+	r0 -= r1;					\
+	exit;						\
+"	:
+	: __imm(bpf_ktime_get_ns)
+	: __clobber_all);
+}
+
+SEC("socket")
+__description("check deducing bounds from non-const, jmp32, <non_const> == <const>")
+__success __retval(0)
+__naked void deducing_bounds_from_non_const_3(void)
+{
+	asm volatile ("					\
+	call %[bpf_ktime_get_ns];			\
+	if w0 < 4 goto l0_%=;				\
+	w2 = 3;						\
+	if w0 == w2 goto l1_%=;				\
+l0_%=:							\
+	r0 = 0;						\
+	exit;						\
+l1_%=:							\
+	r0 -= r1;					\
+	exit;						\
+"	:
+	: __imm(bpf_ktime_get_ns)
+	: __clobber_all);
+}
+
+SEC("socket")
+__description("check deducing bounds from non-const, jmp32, <non_const> != <const>")
+__success __retval(0)
+__naked void deducing_bounds_from_non_const_4(void)
+{
+	asm volatile ("					\
+	call %[bpf_ktime_get_ns];			\
+	if w0 < 3 goto l0_%=;				\
+	w2 = 2;						\
+	if w0 != w2 goto l0_%=;				\
+	goto l1_%=;					\
+l0_%=:							\
+	r0 = 0;						\
+	exit;						\
+l1_%=:							\
+	r0 -= r1;					\
+	exit;						\
+"	:
+	: __imm(bpf_ktime_get_ns)
+	: __clobber_all);
+}
+
+char _license[] SEC("license") = "GPL";