[PATCH perf/core 16/22] selftests/bpf: Add uprobe syscall sigill signal test

Jiri Olsa
2025-04-21T21:47:45Z

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

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
.../selftests/bpf/prog_tests/uprobe_syscall.c | 36 +++++++++++++++++++
1 file changed, 36 insertions(+)

diff --git a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
index 57ef1207c3f5..f001986981ab 100644
--- a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
+++ b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
@@ -691,6 +691,40 @@ 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"))
@@ -711,6 +745,8 @@ 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)
--
2.49.0