Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 95 insertions, 0 deletions

diff --git a/tools/testing/selftests/x86/vdso_restorer.c b/tools/testing/selftests/x86/vdso_restorer.c
new file mode 100644
index 000000000..fe99f2434
--- /dev/null
+++ b/tools/testing/selftests/x86/vdso_restorer.c
@@ -0,0 +1,95 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * vdso_restorer.c - tests vDSO-based signal restore
+ * Copyright (c) 2015 Andrew Lutomirski
+ *
+ * This makes sure that sa_restorer == NULL keeps working on 32-bit
+ * configurations.  Modern glibc doesn't use it under any circumstances,
+ * so it's easy to overlook breakage.
+ *
+ * 64-bit userspace has never supported sa_restorer == NULL, so this is
+ * 32-bit only.
+ */
+
+#define _GNU_SOURCE
+
+#include <err.h>
+#include <stdio.h>
+#include <dlfcn.h>
+#include <string.h>
+#include <signal.h>
+#include <unistd.h>
+#include <syscall.h>
+#include <sys/syscall.h>
+
+/* Open-code this -- the headers are too messy to easily use them. */
+struct real_sigaction {
+	void *handler;
+	unsigned long flags;
+	void *restorer;
+	unsigned int mask[2];
+};
+
+static volatile sig_atomic_t handler_called;
+
+static void handler_with_siginfo(int sig, siginfo_t *info, void *ctx_void)
+{
+	handler_called = 1;
+}
+
+static void handler_without_siginfo(int sig)
+{
+	handler_called = 1;
+}
+
+int main()
+{
+	int nerrs = 0;
+	struct real_sigaction sa;
+
+	void *vdso = dlopen("linux-vdso.so.1",
+			    RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
+	if (!vdso)
+		vdso = dlopen("linux-gate.so.1",
+			      RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
+	if (!vdso) {
+		printf("[SKIP]\tFailed to find vDSO.  Tests are not expected to work.\n");
+		return 0;
+	}
+
+	memset(&sa, 0, sizeof(sa));
+	sa.handler = handler_with_siginfo;
+	sa.flags = SA_SIGINFO;
+	sa.restorer = NULL;	/* request kernel-provided restorer */
+
+	printf("[RUN]\tRaise a signal, SA_SIGINFO, sa.restorer == NULL\n");
+
+	if (syscall(SYS_rt_sigaction, SIGUSR1, &sa, NULL, 8) != 0)
+		err(1, "raw rt_sigaction syscall");
+
+	raise(SIGUSR1);
+
+	if (handler_called) {
+		printf("[OK]\tSA_SIGINFO handler returned successfully\n");
+	} else {
+		printf("[FAIL]\tSA_SIGINFO handler was not called\n");
+		nerrs++;
+	}
+
+	printf("[RUN]\tRaise a signal, !SA_SIGINFO, sa.restorer == NULL\n");
+
+	sa.flags = 0;
+	sa.handler = handler_without_siginfo;
+	if (syscall(SYS_sigaction, SIGUSR1, &sa, 0) != 0)
+		err(1, "raw sigaction syscall");
+	handler_called = 0;
+
+	raise(SIGUSR1);
+
+	if (handler_called) {
+		printf("[OK]\t!SA_SIGINFO handler returned successfully\n");
+	} else {
+		printf("[FAIL]\t!SA_SIGINFO handler was not called\n");
+		nerrs++;
+	}
+}