[RFCv2,17/18] selftests/bpf: Add uprobe syscall sigill signal test

Commit Message

Jiri Olsa Feb. 24, 2025, 2:01 p.m. UTC

Make sure that calling uprobe syscall from outside uprobe trampoline
results in sigill signal.

Signed-off-by: Jiri Olsa <[e-mail]>
---
 .../selftests/bpf/prog_tests/uprobe_syscall.c | 36 +++++++++++++++++++
 1 file changed, 36 insertions(+)

Patch

diff --git a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
index 3f320da4ac46..c5894ddc5b5e 100644
--- a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
+++ b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
@@ -631,6 +631,40 @@  static void test_uprobe_race(void)
 		pthread_join(threads[i], NULL);
 }
 
+#ifndef __NR_uprobe
+#define __NR_uprobe 336
+#endif
+
+static void test_uprobe_sigill(void)
+{
+	int status, err, pid;
+
+	pid = fork();
+	if (!ASSERT_GE(pid, 0, "fork"))
+		return;
+	/* child */
+	if (pid == 0) {
+		asm volatile (
+			"pushq %rax\n"
+			"pushq %rcx\n"
+			"pushq %r11\n"
+			"movq $" __stringify(__NR_uprobe) ", %rax\n"
+			"syscall\n"
+			"popq %r11\n"
+			"popq %rcx\n"
+			"retq\n"
+		);
+		exit(0);
+	}
+
+	err = waitpid(pid, &status, 0);
+	ASSERT_EQ(err, pid, "waitpid");
+
+	/* verify the child got killed with SIGILL */
+	ASSERT_EQ(WIFSIGNALED(status), 1, "WIFSIGNALED");
+	ASSERT_EQ(WTERMSIG(status), SIGILL, "WTERMSIG");
+}
+
 static void __test_uprobe_syscall(void)
 {
 	if (test__start_subtest("uretprobe_regs_equal"))
@@ -649,6 +683,8 @@  static void __test_uprobe_syscall(void)
 		test_uprobe_usdt();
 	if (test__start_subtest("uprobe_race"))
 		test_uprobe_race();
+	if (test__start_subtest("uprobe_sigill"))
+		test_uprobe_sigill();
 }
 #else
 static void __test_uprobe_syscall(void)