diff mbox series

[PATCHv3,bpf-next,25/26] selftests/bpf: Add uprobe_multi pid filter tests

Message ID 20230630083344.984305-26-jolsa@kernel.org (mailing list archive)
State Changes Requested
Delegated to: BPF
Headers show
Series bpf: Add multi uprobe link | expand

Checks

Context Check Description
netdev/series_format fail Series longer than 15 patches (and no cover letter)
netdev/tree_selection success Clearly marked for bpf-next, async
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 8 this patch: 8
netdev/cc_maintainers warning 6 maintainers not CCed: kpsingh@kernel.org martin.lau@linux.dev shuah@kernel.org song@kernel.org mykolal@fb.com linux-kselftest@vger.kernel.org
netdev/build_clang fail Errors and warnings before: 18 this patch: 18
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 8 this patch: 8
netdev/checkpatch warning CHECK: Alignment should match open parenthesis WARNING: line length of 81 exceeds 80 columns WARNING: line length of 84 exceeds 80 columns WARNING: line length of 86 exceeds 80 columns WARNING: line length of 87 exceeds 80 columns WARNING: line length of 92 exceeds 80 columns WARNING: line length of 94 exceeds 80 columns
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-VM_Test-1 success Logs for ${{ matrix.test }} on ${{ matrix.arch }} with ${{ matrix.toolchain_full }}
bpf/vmtest-bpf-next-VM_Test-2 success Logs for ShellCheck
bpf/vmtest-bpf-next-VM_Test-3 success Logs for build for aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-4 success Logs for build for s390x with gcc
bpf/vmtest-bpf-next-VM_Test-5 success Logs for build for x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-6 fail Logs for build for x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-7 success Logs for set-matrix
bpf/vmtest-bpf-next-VM_Test-8 success Logs for veristat

Commit Message

Jiri Olsa June 30, 2023, 8:33 a.m. UTC
Running api and link tests also with pid filter and checking
the probe gets executed only for specific pid.

Spawning extra process to trigger attached uprobes and checking
we get correct counts from executed programs.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 .../bpf/prog_tests/uprobe_multi_test.c        | 131 ++++++++++++++++--
 .../selftests/bpf/progs/uprobe_multi.c        |   6 +-
 2 files changed, 125 insertions(+), 12 deletions(-)
diff mbox series

Patch

diff --git a/tools/testing/selftests/bpf/prog_tests/uprobe_multi_test.c b/tools/testing/selftests/bpf/prog_tests/uprobe_multi_test.c
index b12dc1f992e5..8ca7a45e21e6 100644
--- a/tools/testing/selftests/bpf/prog_tests/uprobe_multi_test.c
+++ b/tools/testing/selftests/bpf/prog_tests/uprobe_multi_test.c
@@ -23,14 +23,86 @@  noinline void uprobe_multi_func_3(void)
 	asm volatile ("");
 }
 
-static void uprobe_multi_test_run(struct uprobe_multi *skel)
+struct child {
+	int go[2];
+	int pid;
+};
+
+static void release_child(struct child *child)
+{
+	int child_status;
+
+	if (!child)
+		return;
+	close(child->go[1]);
+	close(child->go[0]);
+	if (child->pid > 0)
+		waitpid(child->pid, &child_status, 0);
+}
+
+static void kick_child(struct child *child)
+{
+	char c = 1;
+
+	if (child) {
+		write(child->go[1], &c, 1);
+		release_child(child);
+	}
+	fflush(NULL);
+}
+
+static struct child *spawn_child(void)
+{
+	static struct child child;
+	int err;
+	int c;
+
+	/* pid filter */
+	if (!ASSERT_OK(pipe(child.go), "pipe"))
+		return NULL;
+
+	child.pid = fork();
+	if (child.pid < 0) {
+		release_child(&child);
+		return NULL;
+	}
+
+	/* child */
+	if (child.pid == 0) {
+		close(child.go[1]);
+		fflush(NULL);
+		/* wait for parent's kick */
+		err = read(child.go[0], &c, 1);
+		if (!ASSERT_EQ(err, 1, "child_read_pipe"))
+			exit(err);
+
+		uprobe_multi_func_1();
+		uprobe_multi_func_2();
+		uprobe_multi_func_3();
+
+		exit(errno);
+	}
+
+	return &child;
+}
+
+static void uprobe_multi_test_run(struct uprobe_multi *skel, struct child *child)
 {
 	skel->bss->uprobe_multi_func_1_addr = (__u64) uprobe_multi_func_1;
 	skel->bss->uprobe_multi_func_2_addr = (__u64) uprobe_multi_func_2;
 	skel->bss->uprobe_multi_func_3_addr = (__u64) uprobe_multi_func_3;
 
 	skel->bss->user_ptr = test_data;
-	skel->bss->pid = getpid();
+
+	/*
+	 * Disable pid check in bpf program if we are pid filter test,
+	 * because the probe should be executed only by child->pid
+	 * passed at the probe attach.
+	 */
+	skel->bss->pid = child ? 0 : getpid();
+
+	if (child)
+		kick_child(child);
 
 	/* trigger all probes */
 	uprobe_multi_func_1();
@@ -50,6 +122,9 @@  static void uprobe_multi_test_run(struct uprobe_multi *skel)
 	ASSERT_EQ(skel->bss->uretprobe_multi_func_3_result, 2, "uretprobe_multi_func_3_result");
 
 	ASSERT_EQ(skel->bss->uprobe_multi_sleep_result, 6, "uprobe_multi_sleep_result");
+
+	if (child)
+		ASSERT_EQ(skel->bss->child_pid, child->pid, "uprobe_multi_child_pid");
 }
 
 static void test_skel_api(void)
@@ -65,17 +140,19 @@  static void test_skel_api(void)
 	if (!ASSERT_OK(err, "uprobe_multi__attach"))
 		goto cleanup;
 
-	uprobe_multi_test_run(skel);
+	uprobe_multi_test_run(skel, NULL);
 
 cleanup:
 	uprobe_multi__destroy(skel);
 }
 
 static void
-test_attach_api(const char *binary, const char *pattern, struct bpf_uprobe_multi_opts *opts)
+__test_attach_api(const char *binary, const char *pattern, struct bpf_uprobe_multi_opts *opts,
+		  struct child *child)
 {
 	struct bpf_link *link1 = NULL, *link2 = NULL;
 	struct bpf_link *link3 = NULL, *link4 = NULL;
+	pid_t pid = child ? child->pid : -1;
 	struct uprobe_multi *skel = NULL;
 
 	skel = uprobe_multi__open_and_load();
@@ -83,30 +160,30 @@  test_attach_api(const char *binary, const char *pattern, struct bpf_uprobe_multi
 		goto cleanup;
 
 	opts->retprobe = false;
-	link1 = bpf_program__attach_uprobe_multi(skel->progs.test_uprobe, -1,
+	link1 = bpf_program__attach_uprobe_multi(skel->progs.test_uprobe, pid,
 						      binary, pattern, opts);
 	if (!ASSERT_OK_PTR(link1, "bpf_program__attach_uprobe_multi"))
 		goto cleanup;
 
 	opts->retprobe = true;
-	link2 = bpf_program__attach_uprobe_multi(skel->progs.test_uretprobe, -1,
+	link2 = bpf_program__attach_uprobe_multi(skel->progs.test_uretprobe, pid,
 						      binary, pattern, opts);
 	if (!ASSERT_OK_PTR(link2, "bpf_program__attach_uprobe_multi_retprobe"))
 		goto cleanup;
 
 	opts->retprobe = false;
-	link3 = bpf_program__attach_uprobe_multi(skel->progs.test_uprobe_sleep, -1,
+	link3 = bpf_program__attach_uprobe_multi(skel->progs.test_uprobe_sleep, pid,
 						      binary, pattern, opts);
 	if (!ASSERT_OK_PTR(link1, "bpf_program__attach_uprobe_multi"))
 		goto cleanup;
 
 	opts->retprobe = true;
-	link4 = bpf_program__attach_uprobe_multi(skel->progs.test_uretprobe_sleep, -1,
+	link4 = bpf_program__attach_uprobe_multi(skel->progs.test_uretprobe_sleep, pid,
 						      binary, pattern, opts);
 	if (!ASSERT_OK_PTR(link2, "bpf_program__attach_uprobe_multi_retprobe"))
 		goto cleanup;
 
-	uprobe_multi_test_run(skel);
+	uprobe_multi_test_run(skel, child);
 
 cleanup:
 	bpf_link__destroy(link4);
@@ -116,6 +193,22 @@  test_attach_api(const char *binary, const char *pattern, struct bpf_uprobe_multi
 	uprobe_multi__destroy(skel);
 }
 
+static void
+test_attach_api(const char *binary, const char *pattern, struct bpf_uprobe_multi_opts *opts)
+{
+	struct child *child;
+
+	/* no pid filter */
+	__test_attach_api(binary, pattern, opts, NULL);
+
+	/* pid filter */
+	child = spawn_child();
+	if (!child)
+		return;
+
+	__test_attach_api(binary, pattern, opts, child);
+}
+
 static void test_attach_api_pattern(void)
 {
 	LIBBPF_OPTS(bpf_uprobe_multi_opts, opts);
@@ -138,7 +231,7 @@  static void test_attach_api_syms(void)
 	test_attach_api("/proc/self/exe", NULL, &opts);
 }
 
-static void test_link_api(void)
+static void __test_link_api(struct child *child)
 {
 	int prog_fd, link1_fd = -1, link2_fd = -1, link3_fd = -1, link4_fd = -1;
 	LIBBPF_OPTS(bpf_link_create_opts, opts);
@@ -159,6 +252,7 @@  static void test_link_api(void)
 	opts.uprobe_multi.path = path;
 	opts.uprobe_multi.offsets = offsets;
 	opts.uprobe_multi.cnt = ARRAY_SIZE(syms);
+	opts.uprobe_multi.pid = child ? child->pid : 0;
 
 	skel = uprobe_multi__open_and_load();
 	if (!ASSERT_OK_PTR(skel, "uprobe_multi__open_and_load"))
@@ -187,7 +281,7 @@  static void test_link_api(void)
 	link4_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_UPROBE_MULTI, &opts);
 	if (!ASSERT_GE(link2_fd, 0, "link4_fd"))
 		goto cleanup;
-	uprobe_multi_test_run(skel);
+	uprobe_multi_test_run(skel, child);
 
 cleanup:
 	if (link1_fd >= 0)
@@ -203,6 +297,21 @@  static void test_link_api(void)
 	free(offsets);
 }
 
+void test_link_api(void)
+{
+	struct child *child;
+
+	/* no pid filter */
+	__test_link_api(NULL);
+
+	/* pid filter */
+	child = spawn_child();
+	if (!child)
+		return;
+
+	__test_link_api(child);
+}
+
 static inline __u64 get_time_ns(void)
 {
 	struct timespec t;
diff --git a/tools/testing/selftests/bpf/progs/uprobe_multi.c b/tools/testing/selftests/bpf/progs/uprobe_multi.c
index cd73139dc881..1086312b5d1e 100644
--- a/tools/testing/selftests/bpf/progs/uprobe_multi.c
+++ b/tools/testing/selftests/bpf/progs/uprobe_multi.c
@@ -21,6 +21,8 @@  __u64 uretprobe_multi_func_3_result = 0;
 __u64 uprobe_multi_sleep_result = 0;
 
 int pid = 0;
+int child_pid = 0;
+
 bool test_cookie = false;
 void *user_ptr = 0;
 
@@ -34,7 +36,9 @@  static __always_inline bool verify_sleepable_user_copy(void)
 
 static void uprobe_multi_check(void *ctx, bool is_return, bool is_sleep)
 {
-	if (bpf_get_current_pid_tgid() >> 32 != pid)
+	child_pid = bpf_get_current_pid_tgid() >> 32;
+
+	if (pid && child_pid != pid)
 		return;
 
 	__u64 cookie = test_cookie ? bpf_get_attach_cookie(ctx) : 0;