[bpf-next,v2,16/16] selftests/bpf: Add MSan annotations

Commit Message

Ilya Leoshkevich Feb. 10, 2023, 12:12 a.m. UTC

eBPF selftests produce a few false positives with MSan. 3 of them have
to do with sending uninitalized data via a socket. Another one is
PERF_EVENT_IOC_QUERY_BPF, which is not known to MSan. Silence all of
them using libbpf_mark_mem_written().

Signed-off-by: Ilya Leoshkevich <[e-mail]>
---
 tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c      | 3 +++
 tools/testing/selftests/bpf/prog_tests/send_signal.c     | 2 ++
 tools/testing/selftests/bpf/prog_tests/tp_attach_query.c | 4 ++++
 tools/testing/selftests/bpf/prog_tests/xdp_bonding.c     | 3 +++
 4 files changed, 12 insertions(+)

Patch

diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c b/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c
index e980188d4124..c75a3357cd06 100644
--- a/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c
+++ b/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c
@@ -4,6 +4,7 @@ 
 #include <linux/err.h>
 #include <netinet/tcp.h>
 #include <test_progs.h>
+#include <bpf/libbpf_internal.h>
 #include "network_helpers.h"
 #include "bpf_dctcp.skel.h"
 #include "bpf_cubic.skel.h"
@@ -39,6 +40,8 @@  static void *server(void *arg)
 	ssize_t nr_sent = 0, bytes = 0;
 	char batch[1500];
 
+	libbpf_mark_mem_written(batch, sizeof(batch));
+
 	fd = accept(lfd, NULL, NULL);
 	while (fd == -1) {
 		if (errno == EINTR)
diff --git a/tools/testing/selftests/bpf/prog_tests/send_signal.c b/tools/testing/selftests/bpf/prog_tests/send_signal.c
index d63a20fbed33..11e91fc7a67f 100644
--- a/tools/testing/selftests/bpf/prog_tests/send_signal.c
+++ b/tools/testing/selftests/bpf/prog_tests/send_signal.c
@@ -1,5 +1,6 @@ 
 // SPDX-License-Identifier: GPL-2.0
 #include <test_progs.h>
+#include <bpf/libbpf_internal.h>
 #include <sys/time.h>
 #include <sys/resource.h>
 #include "test_send_signal_kern.skel.h"
@@ -58,6 +59,7 @@  static void test_send_signal_common(struct perf_event_attr *attr,
 		ASSERT_OK(setpriority(PRIO_PROCESS, 0, -20), "setpriority");
 
 		/* notify parent signal handler is installed */
+		libbpf_mark_mem_written(buf, 1);
 		ASSERT_EQ(write(pipe_c2p[1], buf, 1), 1, "pipe_write");
 
 		/* make sure parent enabled bpf program to send_signal */
diff --git a/tools/testing/selftests/bpf/prog_tests/tp_attach_query.c b/tools/testing/selftests/bpf/prog_tests/tp_attach_query.c
index 770fcc3bb1ba..727898e905fe 100644
--- a/tools/testing/selftests/bpf/prog_tests/tp_attach_query.c
+++ b/tools/testing/selftests/bpf/prog_tests/tp_attach_query.c
@@ -1,5 +1,6 @@ 
 // SPDX-License-Identifier: GPL-2.0
 #include <test_progs.h>
+#include <bpf/libbpf_internal.h>
 
 void serial_test_tp_attach_query(void)
 {
@@ -66,6 +67,7 @@  void serial_test_tp_attach_query(void)
 		if (i == 0) {
 			/* check NULL prog array query */
 			query->ids_len = num_progs;
+			libbpf_mark_var_written(query->prog_cnt);
 			err = ioctl(pmu_fd[i], PERF_EVENT_IOC_QUERY_BPF, query);
 			if (CHECK(err || query->prog_cnt != 0,
 				  "perf_event_ioc_query_bpf",
@@ -115,6 +117,8 @@  void serial_test_tp_attach_query(void)
 			  "err %d errno %d query->prog_cnt %u\n",
 			  err, errno, query->prog_cnt))
 			goto cleanup3;
+		libbpf_mark_mem_written(query->ids,
+					query->ids_len * sizeof(__u32));
 		for (j = 0; j < i + 1; j++)
 			if (CHECK(saved_prog_ids[j] != query->ids[j],
 				  "perf_event_ioc_query_bpf",
diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_bonding.c b/tools/testing/selftests/bpf/prog_tests/xdp_bonding.c
index 5e3a26b15ec6..e6334f254675 100644
--- a/tools/testing/selftests/bpf/prog_tests/xdp_bonding.c
+++ b/tools/testing/selftests/bpf/prog_tests/xdp_bonding.c
@@ -14,6 +14,7 @@ 
 #include <net/if.h>
 #include <linux/if_link.h>
 #include "test_progs.h"
+#include "bpf/libbpf_internal.h"
 #include "network_helpers.h"
 #include <linux/if_bonding.h>
 #include <linux/limits.h>
@@ -224,6 +225,8 @@  static int send_udp_packets(int vary_dst_ip)
 	int i, s = -1;
 	int ifindex;
 
+	libbpf_mark_mem_written(buf, sizeof(buf));
+
 	s = socket(AF_PACKET, SOCK_RAW, IPPROTO_RAW);
 	if (!ASSERT_GE(s, 0, "socket"))
 		goto err;