diff mbox series

[bpf-next,4/4] selftests/bpf: Test subprog jit when toggle bpf_jit_harden repeatedly

Message ID 20220309123321.2400262-5-houtao1@huawei.com (mailing list archive)
State Accepted
Commit ad13baf4569152b00de11949b8c93aaa83c1243f
Delegated to: BPF
Headers show
Series fixes for bpf_jit_harden race | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for bpf-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers warning 2 maintainers not CCed: linux-kselftest@vger.kernel.org shuah@kernel.org
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 103 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
bpf/vmtest-bpf-next-PR success PR summary
bpf/vmtest-bpf-next success VM_Test

Commit Message

Hou Tao March 9, 2022, 12:33 p.m. UTC
When bpf_jit_harden is toggled between 0 and 2, subprog jit may fail
due to inconsistent twice read values of bpf_jit_harden during jit. So
add a test to ensure the problem is fixed.

Signed-off-by: Hou Tao <houtao1@huawei.com>
---
 .../selftests/bpf/prog_tests/subprogs.c       | 77 ++++++++++++++++---
 1 file changed, 68 insertions(+), 9 deletions(-)
diff mbox series

Patch

diff --git a/tools/testing/selftests/bpf/prog_tests/subprogs.c b/tools/testing/selftests/bpf/prog_tests/subprogs.c
index 3f3d2ac4dd57..903f35a9e62e 100644
--- a/tools/testing/selftests/bpf/prog_tests/subprogs.c
+++ b/tools/testing/selftests/bpf/prog_tests/subprogs.c
@@ -1,32 +1,83 @@ 
 // SPDX-License-Identifier: GPL-2.0
 /* Copyright (c) 2020 Facebook */
 #include <test_progs.h>
-#include <time.h>
 #include "test_subprogs.skel.h"
 #include "test_subprogs_unused.skel.h"
 
-static int duration;
+struct toggler_ctx {
+	int fd;
+	bool stop;
+};
 
-void test_subprogs(void)
+static void *toggle_jit_harden(void *arg)
+{
+	struct toggler_ctx *ctx = arg;
+	char two = '2';
+	char zero = '0';
+
+	while (!ctx->stop) {
+		lseek(ctx->fd, SEEK_SET, 0);
+		write(ctx->fd, &two, sizeof(two));
+		lseek(ctx->fd, SEEK_SET, 0);
+		write(ctx->fd, &zero, sizeof(zero));
+	}
+
+	return NULL;
+}
+
+static void test_subprogs_with_jit_harden_toggling(void)
+{
+	struct toggler_ctx ctx;
+	pthread_t toggler;
+	int err;
+	unsigned int i, loop = 10;
+
+	ctx.fd = open("/proc/sys/net/core/bpf_jit_harden", O_RDWR);
+	if (!ASSERT_GE(ctx.fd, 0, "open bpf_jit_harden"))
+		return;
+
+	ctx.stop = false;
+	err = pthread_create(&toggler, NULL, toggle_jit_harden, &ctx);
+	if (!ASSERT_OK(err, "new toggler"))
+		goto out;
+
+	/* Make toggler thread to run */
+	usleep(1);
+
+	for (i = 0; i < loop; i++) {
+		struct test_subprogs *skel = test_subprogs__open_and_load();
+
+		if (!ASSERT_OK_PTR(skel, "skel open"))
+			break;
+		test_subprogs__destroy(skel);
+	}
+
+	ctx.stop = true;
+	pthread_join(toggler, NULL);
+out:
+	close(ctx.fd);
+}
+
+static void test_subprogs_alone(void)
 {
 	struct test_subprogs *skel;
 	struct test_subprogs_unused *skel2;
 	int err;
 
 	skel = test_subprogs__open_and_load();
-	if (CHECK(!skel, "skel_open", "failed to open skeleton\n"))
+	if (!ASSERT_OK_PTR(skel, "skel_open"))
 		return;
 
 	err = test_subprogs__attach(skel);
-	if (CHECK(err, "skel_attach", "failed to attach skeleton: %d\n", err))
+	if (!ASSERT_OK(err, "skel attach"))
 		goto cleanup;
 
 	usleep(1);
 
-	CHECK(skel->bss->res1 != 12, "res1", "got %d, exp %d\n", skel->bss->res1, 12);
-	CHECK(skel->bss->res2 != 17, "res2", "got %d, exp %d\n", skel->bss->res2, 17);
-	CHECK(skel->bss->res3 != 19, "res3", "got %d, exp %d\n", skel->bss->res3, 19);
-	CHECK(skel->bss->res4 != 36, "res4", "got %d, exp %d\n", skel->bss->res4, 36);
+	ASSERT_EQ(skel->bss->res1, 12, "res1");
+	ASSERT_EQ(skel->bss->res2, 17, "res2");
+	ASSERT_EQ(skel->bss->res3, 19, "res3");
+	ASSERT_EQ(skel->bss->res4, 36, "res4");
 
 	skel2 = test_subprogs_unused__open_and_load();
 	ASSERT_OK_PTR(skel2, "unused_progs_skel");
@@ -35,3 +86,11 @@  void test_subprogs(void)
 cleanup:
 	test_subprogs__destroy(skel);
 }
+
+void test_subprogs(void)
+{
+	if (test__start_subtest("subprogs_alone"))
+		test_subprogs_alone();
+	if (test__start_subtest("subprogs_and_jit_harden"))
+		test_subprogs_with_jit_harden_toggling();
+}