@@ -30,3 +30,4 @@ hwtstamp_config
rxtimestamp
timestamping
txtimestamp
+so_netns_cookie
@@ -28,7 +28,7 @@ TEST_GEN_FILES = socket nettest
TEST_GEN_FILES += psock_fanout psock_tpacket msg_zerocopy reuseport_addr_any
TEST_GEN_FILES += tcp_mmap tcp_inq psock_snd txring_overwrite
TEST_GEN_FILES += udpgso udpgso_bench_tx udpgso_bench_rx ip_defrag
-TEST_GEN_FILES += so_txtime ipv6_flowlabel ipv6_flowlabel_mgr
+TEST_GEN_FILES += so_txtime ipv6_flowlabel ipv6_flowlabel_mgr so_netns_cookie
TEST_GEN_FILES += tcp_fastopen_backup_key
TEST_GEN_FILES += fin_ack_lat
TEST_GEN_FILES += reuseaddr_ports_exhausted
@@ -1,4 +1,5 @@
CONFIG_USER_NS=y
+CONFIG_NET_NS=y
CONFIG_BPF_SYSCALL=y
CONFIG_TEST_BPF=m
CONFIG_NUMA=y
new file mode 100644
@@ -0,0 +1,61 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sched.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#ifndef SO_NETNS_COOKIE
+#define SO_NETNS_COOKIE 71
+#endif
+
+#define pr_err(fmt, ...) \
+ ({ \
+ fprintf(stderr, "%s:%d:" fmt ": %m\n", \
+ __func__, __LINE__, ##__VA_ARGS__); \
+ 1; \
+ })
+
+int main(int argc, char *argvp[])
+{
+ uint64_t cookie1, cookie2;
+ socklen_t vallen;
+ int sock1, sock2;
+
+ sock1 = socket(AF_INET, SOCK_STREAM, 0);
+ if (sock1 < 0)
+ return pr_err("Unable to create TCP socket");
+
+ vallen = sizeof(cookie1);
+ if (getsockopt(sock1, SOL_SOCKET, SO_NETNS_COOKIE, &cookie1, &vallen) != 0)
+ return pr_err("getsockopt(SOL_SOCKET, SO_NETNS_COOKIE)");
+
+ if (!cookie1)
+ return pr_err("SO_NETNS_COOKIE returned zero cookie");
+
+ if (unshare(CLONE_NEWNET))
+ return pr_err("unshare");
+
+ sock2 = socket(AF_INET, SOCK_STREAM, 0);
+ if (sock2 < 0)
+ return pr_err("Unable to create TCP socket");
+
+ vallen = sizeof(cookie2);
+ if (getsockopt(sock2, SOL_SOCKET, SO_NETNS_COOKIE, &cookie2, &vallen) != 0)
+ return pr_err("getsockopt(SOL_SOCKET, SO_NETNS_COOKIE)");
+
+ if (!cookie2)
+ return pr_err("SO_NETNS_COOKIE returned zero cookie");
+
+ if (cookie1 == cookie2)
+ return pr_err("SO_NETNS_COOKIE returned identical cookies for distinct ns");
+
+ close(sock1);
+ close(sock2);
+ return 0;
+}
Make sure that SO_NETNS_COOKIE returns a non-zero value, and that sockets from different namespaces have a distinct cookie value. Signed-off-by: Lorenz Bauer <lmb@cloudflare.com> --- tools/testing/selftests/net/.gitignore | 1 + tools/testing/selftests/net/Makefile | 2 +- tools/testing/selftests/net/config | 1 + tools/testing/selftests/net/so_netns_cookie.c | 61 +++++++++++++++++++ 4 files changed, 64 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/net/so_netns_cookie.c