[PATCH AUTOSEL 5.4 071/330] selftests/bpf: De-flake test_tcpbpf

[PATCH AUTOSEL 5.4 071/330] selftests/bpf: De-flake test_tcpbpf

[Sasha Levin]

From: Stanislav Fomichev <sdf@google.com>

[ Upstream commit ef8c84effce3c7a0b8196fcda8f430c815ab511c ]

It looks like BPF program that handles BPF_SOCK_OPS_STATE_CB state
can race with the bpf_map_lookup_elem("global_map"); I sometimes
see the failures in this test and re-running helps.

Since we know that we expect the callback to be called 3 times (one
time for listener socket, two times for both ends of the connection),
let's export this number and add simple retry logic around that.

Also, let's make EXPECT_EQ() not return on failure, but continue
evaluating all conditions; that should make potential debugging
easier.

With this fix in place I don't observe the flakiness anymore.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Lawrence Brakmo <brakmo@fb.com>
Link: https://lore.kernel.org/bpf/20191204190955.170934-1-sdf@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 .../selftests/bpf/progs/test_tcpbpf_kern.c    |  1 +
 tools/testing/selftests/bpf/test_tcpbpf.h     |  1 +
 .../testing/selftests/bpf/test_tcpbpf_user.c  | 25 +++++++++++++------
 3 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/tools/testing/selftests/bpf/progs/test_tcpbpf_kern.c b/tools/testing/selftests/bpf/progs/test_tcpbpf_kern.c
index 2e233613d1fc0..7fa4595d2b66b 100644
--- a/tools/testing/selftests/bpf/progs/test_tcpbpf_kern.c
+++ b/tools/testing/selftests/bpf/progs/test_tcpbpf_kern.c
@@ -131,6 +131,7 @@ int bpf_testcb(struct bpf_sock_ops *skops)
 				g.bytes_received = skops->bytes_received;
 				g.bytes_acked = skops->bytes_acked;
 			}
+			g.num_close_events++;
 			bpf_map_update_elem(&global_map, &key, &g,
 					    BPF_ANY);
 		}
diff --git a/tools/testing/selftests/bpf/test_tcpbpf.h b/tools/testing/selftests/bpf/test_tcpbpf.h
index 7bcfa62070056..6220b95cbd02c 100644
--- a/tools/testing/selftests/bpf/test_tcpbpf.h
+++ b/tools/testing/selftests/bpf/test_tcpbpf.h
@@ -13,5 +13,6 @@ struct tcpbpf_globals {
 	__u64 bytes_received;
 	__u64 bytes_acked;
 	__u32 num_listen;
+	__u32 num_close_events;
 };
 #endif
diff --git a/tools/testing/selftests/bpf/test_tcpbpf_user.c b/tools/testing/selftests/bpf/test_tcpbpf_user.c
index 716b4e3be5813..3ae127620463d 100644
--- a/tools/testing/selftests/bpf/test_tcpbpf_user.c
+++ b/tools/testing/selftests/bpf/test_tcpbpf_user.c
@@ -16,6 +16,9 @@
 
 #include "test_tcpbpf.h"
 
+/* 3 comes from one listening socket + both ends of the connection */
+#define EXPECTED_CLOSE_EVENTS		3
+
 #define EXPECT_EQ(expected, actual, fmt)			\
 	do {							\
 		if ((expected) != (actual)) {			\
@@ -23,13 +26,14 @@
 			       "    Actual: %" fmt "\n"		\
 			       "  Expected: %" fmt "\n",	\
 			       (actual), (expected));		\
-			goto err;				\
+			ret--;					\
 		}						\
 	} while (0)
 
 int verify_result(const struct tcpbpf_globals *result)
 {
 	__u32 expected_events;
+	int ret = 0;
 
 	expected_events = ((1 << BPF_SOCK_OPS_TIMEOUT_INIT) |
 			   (1 << BPF_SOCK_OPS_RWND_INIT) |
@@ -48,15 +52,15 @@ int verify_result(const struct tcpbpf_globals *result)
 	EXPECT_EQ(0x80, result->bad_cb_test_rv, PRIu32);
 	EXPECT_EQ(0, result->good_cb_test_rv, PRIu32);
 	EXPECT_EQ(1, result->num_listen, PRIu32);
+	EXPECT_EQ(EXPECTED_CLOSE_EVENTS, result->num_close_events, PRIu32);
 
-	return 0;
-err:
-	return -1;
+	return ret;
 }
 
 int verify_sockopt_result(int sock_map_fd)
 {
 	__u32 key = 0;
+	int ret = 0;
 	int res;
 	int rv;
 
@@ -69,9 +73,7 @@ int verify_sockopt_result(int sock_map_fd)
 	rv = bpf_map_lookup_elem(sock_map_fd, &key, &res);
 	EXPECT_EQ(0, rv, "d");
 	EXPECT_EQ(1, res, "d");
-	return 0;
-err:
-	return -1;
+	return ret;
 }
 
 static int bpf_find_map(const char *test, struct bpf_object *obj,
@@ -96,6 +98,7 @@ int main(int argc, char **argv)
 	int error = EXIT_FAILURE;
 	struct bpf_object *obj;
 	int cg_fd = -1;
+	int retry = 10;
 	__u32 key = 0;
 	int rv;
 
@@ -134,12 +137,20 @@ int main(int argc, char **argv)
 	if (sock_map_fd < 0)
 		goto err;
 
+retry_lookup:
 	rv = bpf_map_lookup_elem(map_fd, &key, &g);
 	if (rv != 0) {
 		printf("FAILED: bpf_map_lookup_elem returns %d\n", rv);
 		goto err;
 	}
 
+	if (g.num_close_events != EXPECTED_CLOSE_EVENTS && retry--) {
+		printf("Unexpected number of close events (%d), retrying!\n",
+		       g.num_close_events);
+		usleep(100);
+		goto retry_lookup;
+	}
+
 	if (verify_result(&g)) {
 		printf("FAILED: Wrong stats\n");
 		goto err;
-- 
2.25.1

[PATCH AUTOSEL 5.4 109/330] selftests/ftrace: fix glob selftest

[Sasha Levin]

From: Sven Schnelle <svens@linux.ibm.com>

[ Upstream commit af4ddd607dff7aabd466a4a878e01b9f592a75ab ]

test.d/ftrace/func-filter-glob.tc is failing on s390 because it has
ARCH_INLINE_SPIN_LOCK and friends set to 'y'. So the usual
__raw_spin_lock symbol isn't in the ftrace function list. Change
'*aw*lock' to '*spin*lock' which would hopefully match some of the
locking functions on all platforms.

Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 .../testing/selftests/ftrace/test.d/ftrace/func-filter-glob.tc  | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/func-filter-glob.tc b/tools/testing/selftests/ftrace/test.d/ftrace/func-filter-glob.tc
index 27a54a17da65d..f4e92afab14b2 100644
--- a/tools/testing/selftests/ftrace/test.d/ftrace/func-filter-glob.tc
+++ b/tools/testing/selftests/ftrace/test.d/ftrace/func-filter-glob.tc
@@ -30,7 +30,7 @@ ftrace_filter_check '*schedule*' '^.*schedule.*$'
 ftrace_filter_check 'schedule*' '^schedule.*$'
 
 # filter by *mid*end
-ftrace_filter_check '*aw*lock' '.*aw.*lock$'
+ftrace_filter_check '*pin*lock' '.*pin.*lock$'
 
 # filter by start*mid*
 ftrace_filter_check 'mutex*try*' '^mutex.*try.*'
-- 
2.25.1

[PATCH AUTOSEL 5.4 200/330] selftests/ptrace: add test cases for dead-locks

[Sasha Levin]

From: Bernd Edlinger <bernd.edlinger@hotmail.de>

[ Upstream commit 2de4e82318c7f9d34f4b08599a612cd4cd10bf0b ]

This adds test cases for ptrace deadlocks.

Additionally fixes a compile problem in get_syscall_info.c,
observed with gcc-4.8.4:

get_syscall_info.c: In function 'get_syscall_info':
get_syscall_info.c:93:3: error: 'for' loop initial declarations are only
                                 allowed in C99 mode
   for (unsigned int i = 0; i < ARRAY_SIZE(args); ++i) {
   ^
get_syscall_info.c:93:3: note: use option -std=c99 or -std=gnu99 to compile
                               your code

Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/testing/selftests/ptrace/Makefile   |  4 +-
 tools/testing/selftests/ptrace/vmaccess.c | 86 +++++++++++++++++++++++
 2 files changed, 88 insertions(+), 2 deletions(-)
 create mode 100644 tools/testing/selftests/ptrace/vmaccess.c

diff --git a/tools/testing/selftests/ptrace/Makefile b/tools/testing/selftests/ptrace/Makefile
index c0b7f89f09300..2f1f532c39dbc 100644
--- a/tools/testing/selftests/ptrace/Makefile
+++ b/tools/testing/selftests/ptrace/Makefile
@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0-only
-CFLAGS += -iquote../../../../include/uapi -Wall
+CFLAGS += -std=c99 -pthread -iquote../../../../include/uapi -Wall
 
-TEST_GEN_PROGS := get_syscall_info peeksiginfo
+TEST_GEN_PROGS := get_syscall_info peeksiginfo vmaccess
 
 include ../lib.mk
diff --git a/tools/testing/selftests/ptrace/vmaccess.c b/tools/testing/selftests/ptrace/vmaccess.c
new file mode 100644
index 0000000000000..4db327b445862
--- /dev/null
+++ b/tools/testing/selftests/ptrace/vmaccess.c
@@ -0,0 +1,86 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2020 Bernd Edlinger <bernd.edlinger@hotmail.de>
+ * All rights reserved.
+ *
+ * Check whether /proc/$pid/mem can be accessed without causing deadlocks
+ * when de_thread is blocked with ->cred_guard_mutex held.
+ */
+
+#include "../kselftest_harness.h"
+#include <stdio.h>
+#include <fcntl.h>
+#include <pthread.h>
+#include <signal.h>
+#include <unistd.h>
+#include <sys/ptrace.h>
+
+static void *thread(void *arg)
+{
+	ptrace(PTRACE_TRACEME, 0, 0L, 0L);
+	return NULL;
+}
+
+TEST(vmaccess)
+{
+	int f, pid = fork();
+	char mm[64];
+
+	if (!pid) {
+		pthread_t pt;
+
+		pthread_create(&pt, NULL, thread, NULL);
+		pthread_join(pt, NULL);
+		execlp("true", "true", NULL);
+	}
+
+	sleep(1);
+	sprintf(mm, "/proc/%d/mem", pid);
+	f = open(mm, O_RDONLY);
+	ASSERT_GE(f, 0);
+	close(f);
+	f = kill(pid, SIGCONT);
+	ASSERT_EQ(f, 0);
+}
+
+TEST(attach)
+{
+	int s, k, pid = fork();
+
+	if (!pid) {
+		pthread_t pt;
+
+		pthread_create(&pt, NULL, thread, NULL);
+		pthread_join(pt, NULL);
+		execlp("sleep", "sleep", "2", NULL);
+	}
+
+	sleep(1);
+	k = ptrace(PTRACE_ATTACH, pid, 0L, 0L);
+	ASSERT_EQ(errno, EAGAIN);
+	ASSERT_EQ(k, -1);
+	k = waitpid(-1, &s, WNOHANG);
+	ASSERT_NE(k, -1);
+	ASSERT_NE(k, 0);
+	ASSERT_NE(k, pid);
+	ASSERT_EQ(WIFEXITED(s), 1);
+	ASSERT_EQ(WEXITSTATUS(s), 0);
+	sleep(1);
+	k = ptrace(PTRACE_ATTACH, pid, 0L, 0L);
+	ASSERT_EQ(k, 0);
+	k = waitpid(-1, &s, 0);
+	ASSERT_EQ(k, pid);
+	ASSERT_EQ(WIFSTOPPED(s), 1);
+	ASSERT_EQ(WSTOPSIG(s), SIGSTOP);
+	k = ptrace(PTRACE_DETACH, pid, 0L, 0L);
+	ASSERT_EQ(k, 0);
+	k = waitpid(-1, &s, 0);
+	ASSERT_EQ(k, pid);
+	ASSERT_EQ(WIFEXITED(s), 1);
+	ASSERT_EQ(WEXITSTATUS(s), 0);
+	k = waitpid(-1, NULL, 0);
+	ASSERT_EQ(k, -1);
+	ASSERT_EQ(errno, ECHILD);
+}
+
+TEST_HARNESS_MAIN
-- 
2.25.1

[PATCH AUTOSEL 5.4 318/330] selftests/x86/syscall_nt: Clear weird flags after each test

[Sasha Levin]

From: Andy Lutomirski <luto@kernel.org>

[ Upstream commit a61fa2799ef9bf6c4f54cf7295036577cececc72 ]

Clear the weird flags before logging to improve strace output --
logging results while, say, TF is set does no one any favors.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/907bfa5a42d4475b8245e18b67a04b13ca51ffdb.1593191971.git.luto@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/testing/selftests/x86/syscall_nt.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/testing/selftests/x86/syscall_nt.c b/tools/testing/selftests/x86/syscall_nt.c
index 02309a1950413..a765f62ee7668 100644
--- a/tools/testing/selftests/x86/syscall_nt.c
+++ b/tools/testing/selftests/x86/syscall_nt.c
@@ -59,6 +59,7 @@ static void do_it(unsigned long extraflags)
 	set_eflags(get_eflags() | extraflags);
 	syscall(SYS_getpid);
 	flags = get_eflags();
+	set_eflags(X86_EFLAGS_IF | X86_EFLAGS_FIXED);
 	if ((flags & extraflags) == extraflags) {
 		printf("[OK]\tThe syscall worked and flags are still set\n");
 	} else {
-- 
2.25.1