[PATCH ftrace/core v6 5/5] kselftest, ftrace: Add ftrace IPMODIFY flag test

Masami Hiramatsu
2014-11-21T02:29:56Z

Add ftrace IPMODIFY flag test to selftest/ftrace. The
test checks simple ftrace handler insertion and
combinations of ftrace, kprobe, and jprobe.
This test requires kernel build tree to build a test
kernel module and root privilege to run.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>

---
Changes in v6:
- Fix macros to avoid errors by checkpatch.pl.

Changes in v5:
- Add this test to kselftest.
---
tools/testing/selftests/ftrace/Makefile | 11 +
tools/testing/selftests/ftrace/ipmodify/Makefile | 15 ++
tools/testing/selftests/ftrace/ipmodify/ipmodify.c | 170 ++++++++++++++++++++
.../selftests/ftrace/ipmodify/run_ipmodify.sh | 6 +
4 files changed, 202 insertions(+)
create mode 100644 tools/testing/selftests/ftrace/ipmodify/Makefile
create mode 100644 tools/testing/selftests/ftrace/ipmodify/ipmodify.c
create mode 100644 tools/testing/selftests/ftrace/ipmodify/run_ipmodify.sh

diff --git a/tools/testing/selftests/ftrace/Makefile b/tools/testing/selftests/ftrace/Makefile
index 76cc9f1..69f0b1a 100644
--- a/tools/testing/selftests/ftrace/Makefile
+++ b/tools/testing/selftests/ftrace/Makefile
@@ -1,7 +1,18 @@
+TARGETS += ipmodify
+
all:
+ for TARGET in $(TARGETS); do \
+ make -C $$TARGET; \
+ done;

run_tests:
@/bin/sh ./ftracetest || echo "ftrace selftests: [FAIL]"
+ for TARGET in $(TARGETS); do \
+ make -C $$TARGET run_tests; \
+ done;

clean:
rm -rf logs/*
+ for TARGET in $(TARGETS); do \
+ make -C $$TARGET clean; \
+ done;
diff --git a/tools/testing/selftests/ftrace/ipmodify/Makefile b/tools/testing/selftests/ftrace/ipmodify/Makefile
new file mode 100644
index 0000000..416e9a8
--- /dev/null
+++ b/tools/testing/selftests/ftrace/ipmodify/Makefile
@@ -0,0 +1,15 @@
+BUILDDIR = /lib/modules/$(shell uname -r)/build
+HERE = $(abspath ./)
+
+obj-m := ipmodify.o
+
+ipmodify.ko: ipmodify.c
+ $(MAKE) -C $(BUILDDIR) M=$(HERE) $@
+
+all: ipmodify.ko
+
+run_tests:
+ @/bin/sh ./run_ipmodify.sh || echo "ftrace ipmodify test: [FAIL]"
+
+clean:
+ $(RM) -Rf .*.o.cmd .*.ko.cmd .tmp_versions *.o *.ko *.mod.c modules.order Module.symvers
diff --git a/tools/testing/selftests/ftrace/ipmodify/ipmodify.c b/tools/testing/selftests/ftrace/ipmodify/ipmodify.c
new file mode 100644
index 0000000..85213f8
--- /dev/null
+++ b/tools/testing/selftests/ftrace/ipmodify/ipmodify.c
@@ -0,0 +1,170 @@
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/ftrace.h>
+#include <linux/kprobes.h>
+
+/* Testing the IPMODIFY flag by using kprobe, jprobe, and ftrace handler */
+
+static __used int ipmodify_target_function(int a1, int a2, int a3)
+{
+ return a1 + a2 + a3;
+}
+
+/* Kprobe pre handler (IPMODIFY bit is NOT set) */
+static int kprobe_test_handler(struct kprobe *kp, struct pt_regs *regs)
+{
+ return 0;
+}
+
+static struct kprobe test_kp, __test_kp = {
+ .pre_handler = kprobe_test_handler,
+ .addr = (void *)ipmodify_target_function,
+};
+
+/* Jprobe entry handler (IPMODIFY should be set) */
+static void jprobe_test_handler(int a1, int a2, int a3)
+{
+ jprobe_return();
+}
+
+static struct jprobe test_jp, __test_jp = {
+ .entry = jprobe_test_handler,
+ .kp = {
+ .addr = (void *)ipmodify_target_function,
+ },
+};
+
+/* Ftrace handler (with IPMODIFY flag) */
+static void ftrace_ipmodify_handler(unsigned long a0, unsigned long a1,
+ struct ftrace_ops *op, struct pt_regs *regs)
+{
+}
+
+static struct ftrace_ops test_ops __read_mostly, __test_ops = {
+ .func = ftrace_ipmodify_handler,
+ .flags = FTRACE_OPS_FL_SAVE_REGS | FTRACE_OPS_FL_IPMODIFY,
+};
+
+static void cleanup_probes(void)
+{
+ unregister_kprobe(&test_kp);
+ unregister_jprobe(&test_jp);
+ if (test_ops.flags & FTRACE_OPS_FL_ENABLED)
+ unregister_ftrace_function(&test_ops);
+ test_kp = __test_kp;
+ test_jp = __test_jp;
+}
+
+
+
+/* We'll test various probes on a target function. */
+static int __init ipmodify_init(void)
+{
+ int ret;
+
+ test_kp = __test_kp;
+ test_jp = __test_jp;
+ test_ops = __test_ops;
+
+ /* Setup ftrace filter */
+ ret = ftrace_set_filter_ip(&test_ops,
+ (unsigned long)ipmodify_target_function, 0, 0);
+ if (ret < 0) {
+ ret = pr_err("IPMODIFY test: ftrace_set_filter_ip\t[FAILED]\n");
+ goto err;
+ }
+
+ ret = -EINVAL;
+
+/* For the test case which should pass */
+#define EXP_OK(cond) \
+ do { \
+ if ((cond) < 0) { \
+ pr_cont("[FAIL]\n\t" #cond " is failed\n"); \
+ goto err; \
+ } \
+ } while (0)
+/* For the test case which should fail */
+#define EXP_NG(cond) \
+ do { \
+ if ((cond) >= 0) { \
+ pr_cont("[XPASS]\n\t" #cond " is unexpectedly passed\n");\
+ goto err; \
+ } \
+ } while (0)
+
+ /* Case 1 */
+ pr_info("IPMODIFY test: ipmodify only\t");
+ EXP_OK(register_ftrace_function(&test_ops));
+ ipmodify_target_function(1, 2, 3);
+ pr_cont("[PASS]\n");
+ cleanup_probes();
+
+ /* Case 2 */
+ pr_info("IPMODIFY test: kprobe->ipmodify\t");
+ EXP_OK(register_kprobe(&test_kp));
+ EXP_OK(register_ftrace_function(&test_ops));
+ ipmodify_target_function(2, 3, 4);
+ pr_cont("[PASS]\n");
+ cleanup_probes();
+
+ /* Case 3 */
+ pr_info("IPMODIFY test: jprobe->ipmodify(NG)\t");
+ EXP_OK(register_jprobe(&test_jp));
+ EXP_NG(register_ftrace_function(&test_ops));
+ ipmodify_target_function(3, 4, 5);
+ pr_cont("[PASS]\n");
+ cleanup_probes();
+
+ /* Case 4 */
+ pr_info("IPMODIFY test: ipmodify->kprobe\t");
+ EXP_OK(register_ftrace_function(&test_ops));
+ EXP_OK(register_kprobe(&test_kp));
+ ipmodify_target_function(4, 5, 6);
+ pr_cont("[PASS]\n");
+ cleanup_probes();
+
+ /* Case 5 */
+ pr_info("IPMODIFY test: ipmodify->jprobe(NG)\t");
+ EXP_OK(register_ftrace_function(&test_ops));
+ EXP_NG(register_jprobe(&test_jp));
+ ipmodify_target_function(5, 6, 7);
+ pr_cont("[PASS]\n");
+ cleanup_probes();
+
+ /* Case 6 */
+ pr_info("IPMODIFY test: kprobe->jprobe->ipmodify(NG)\t");
+ EXP_OK(register_kprobe(&test_kp));
+ EXP_OK(register_jprobe(&test_jp));
+ EXP_NG(register_ftrace_function(&test_ops));
+ ipmodify_target_function(6, 7, 8);
+ pr_cont("[PASS]\n");
+ cleanup_probes();
+
+ /* Case 7 */
+ pr_info("IPMODIFY test: kprobe->ipmodify->jprobe(NG)\t");
+ EXP_OK(register_kprobe(&test_kp));
+ EXP_OK(register_ftrace_function(&test_ops));
+ EXP_NG(register_jprobe(&test_jp));
+ ipmodify_target_function(7, 8, 9);
+ pr_cont("[PASS]\n");
+ cleanup_probes();
+
+ /* Case 8 */
+ pr_info("IPMODIFY test: setting notrace filter with ipmodify(NG)\t");
+ EXP_NG(ftrace_set_notrace(&test_ops, "do_fork", 0, 0));
+ pr_cont("[PASS]\n");
+
+ return 0;
+err:
+ cleanup_probes();
+ return ret;
+}
+
+void ipmodify_exit(void)
+{
+}
+
+module_init(ipmodify_init)
+module_exit(ipmodify_exit)
+MODULE_LICENSE("GPL");
diff --git a/tools/testing/selftests/ftrace/ipmodify/run_ipmodify.sh b/tools/testing/selftests/ftrace/ipmodify/run_ipmodify.sh
new file mode 100644
index 0000000..4878d9d
--- /dev/null
+++ b/tools/testing/selftests/ftrace/ipmodify/run_ipmodify.sh
@@ -0,0 +1,6 @@
+#!/bin/sh
+set -e
+insmod ipmodify.ko
+rmmod ipmodify.ko
+dmesg | tail -n 8
+