[Repost as a series, as suggested by Andrew Morton]
Selftest for the pre-coredump signal notification
Signed-off-by: Enke Chen <enkec...@cisco.com>
---
tools/testing/selftests/prctl/Makefile | 2 +-
tools/testing/selftests/prctl/predump-sig-test.c | 160 +++++++++++++++++++++++
2 files changed, 161 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/prctl/predump-sig-test.c
diff --git a/tools/testing/selftests/prctl/Makefile
b/tools/testing/selftests/prctl/Makefile
index c7923b2..f8d60d5 100644
--- a/tools/testing/selftests/prctl/Makefile
+++ b/tools/testing/selftests/prctl/Makefile
@@ -5,7 +5,7 @@ ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/x86/ -e
s/x86_64/x86/)
ifeq ($(ARCH),x86)
TEST_PROGS := disable-tsc-ctxt-sw-stress-test disable-tsc-on-off-stress-test \
- disable-tsc-test
+ disable-tsc-test predump-sig-test
all: $(TEST_PROGS)
include ../lib.mk
diff --git a/tools/testing/selftests/prctl/predump-sig-test.c
b/tools/testing/selftests/prctl/predump-sig-test.c
new file mode 100644
index 0000000..15d62691
--- /dev/null
+++ b/tools/testing/selftests/prctl/predump-sig-test.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018, Enke Chen, Cisco Systems, Inc.
+ *
+ * Tests for prctl(PR_SET_PREDUMP_SIG, ...) / prctl(PR_GET_PREDUMP_SIG, ...)
+ *
+ * When set with prctl(), the specified signal is sent to the parent process
+ * prior to the coredump of a child process.
+ *
+ * Usage: ./predump-sig-test {SIGUSR1 | SIGRT2}
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/wait.h>
+#include <sys/prctl.h>
+#include <signal.h>
+#include <errno.h>
+
+#ifndef PR_SET_PREDUMP_SIG
+#define PR_SET_PREDUMP_SIG 54
+#define PR_GET_PREDUMP_SIG 55
+#endif
+
+#define SIGRT2 (SIGRTMIN + 1)
+
+#define handle_error(msg) \
+ do { perror(msg); exit(EXIT_FAILURE); } while (0)
+
+static sig_idx;
+static siginfo_t siginfo_rcv[2];
+
+static void sigaction_func(int sig, siginfo_t *siginfo, void *arg)
+{
+ memcpy(&siginfo_rcv[sig_idx], siginfo, sizeof(siginfo_t));
+ sig_idx++;
+}
+
+static int set_sigaction(int sig)
+{
+ struct sigaction new_action;
+ int rc;
+
+ memset(&new_action, 0, sizeof(struct sigaction));
+ new_action.sa_sigaction = sigaction_func;
+ new_action.sa_flags = SA_SIGINFO;
+ sigemptyset(&new_action.sa_mask);
+
+ return sigaction(sig, &new_action, NULL);
+}
+
+static int test_prctl(int sig)
+{
+ int sig2, rc;
+
+ rc = prctl(PR_SET_PREDUMP_SIG, sig, 0, 0, 0);
+ if (rc < 0)
+ handle_error("prctl: setting");
+
+ rc = prctl(PR_GET_PREDUMP_SIG, &sig2, 0, 0, 0);
+ if (rc < 0)
+ handle_error("prctl: getting");
+
+ if (sig2 != sig) {
+ printf("prctl: sig %d, post %d\n", sig, sig2);
+ return -1;
+ }
+ return 0;
+}
+
+static void child_fn(void)
+{
+ int rc, sig;
+
+ printf("\nChild pid: %ld\n", (long)getpid());
+
+ /* Test: Child should not inherit the predump_signal */
+ rc = prctl(PR_GET_PREDUMP_SIG, &sig, 0, 0, 0);
+ if (rc < 0)
+ handle_error("prctl: child");
+
+ printf("child: predump_signal %d\n", sig);
+
+ /* Force coredump here */
+ printf("child: calling abort()\n");
+ fflush(stdout);
+ abort();
+}
+
+static int parent_fn(pid_t child_pid)
+{
+ int i, status, count;
+ siginfo_t *si;
+ pid_t w;
+
+ for (count = 0; count < 2; count++) {
+ w = waitpid(child_pid, &status, 0);
+ printf("\nwaitpid: %d\n", w);
+ if (w < 0)
+ perror("waitpid");
+
+ si = &siginfo_rcv[count];
+ printf("signal: si_signo %d, si_pid %ld, si_uid %d\n",
+ si->si_signo, si->si_pid, si->si_uid);
+ printf("siginfo: si_errno %d, si_code %d, si_status %d\n",
+ si->si_errno, si->si_code, si->si_status);
+ }
+ fflush(stdout);
+}
+
+int main(int argc, char *argv[])
+{
+ pid_t child_pid;
+ int rc, signo;
+
+ if (argc != 2) {
+ printf("invalid number of arguments\n");
+ exit(EXIT_FAILURE);
+ }
+
+ if (strcmp(argv[1], "SIGUSR1") == 0)
+ signo = SIGUSR1;
+ else if (strcmp(argv[1], "SIGRT2") == 0)
+ signo = SIGRT2;
+ else {
+ printf("invalid argument for signal\n");
+ fflush(stdout);
+ exit(EXIT_FAILURE);
+ }
+
+ rc = set_sigaction(SIGCHLD);
+ if (rc < 0)
+ handle_error("set_sigaction: SIGCHLD");
+
+ if (signo != SIGCHLD) {
+ rc = set_sigaction(signo);
+ if (rc < 0)
+ handle_error("set_sigaction: SIGCHLD");
+ }
+
+ /* Test: prctl() setting */
+ rc = test_prctl(0);
+ printf("prctl: sig %d %s\n", 0, (rc == 0) ? "PASS" : "FAIL");
+
+ rc = test_prctl(signo);
+ printf("prctl: sig %d %s\n", signo, (rc == 0) ? "PASS" : "FAIL");
+
+ child_pid = fork();
+ if (child_pid == -1)
+ handle_error("fork");
+
+ if (child_pid == 0) { /* Code executed by child */
+ child_fn();
+ } else { /* Code executed by parent */
+ parent_fn(child_pid);
+ exit(EXIT_SUCCESS);
+ }
+}
--
1.8.3.1
