Check that NS_GET_COOKIE returns a non-zero value, and that distinct network namespaces have different cookies.
Signed-off-by: Lorenz Bauer lmb@cloudflare.com --- tools/testing/selftests/nsfs/.gitignore | 1 + tools/testing/selftests/nsfs/Makefile | 2 +- tools/testing/selftests/nsfs/netns.c | 57 +++++++++++++++++++++++++ 3 files changed, 59 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/nsfs/netns.c
diff --git a/tools/testing/selftests/nsfs/.gitignore b/tools/testing/selftests/nsfs/.gitignore index ed79ebdf286e..ca31b216215b 100644 --- a/tools/testing/selftests/nsfs/.gitignore +++ b/tools/testing/selftests/nsfs/.gitignore @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0-only owner pidns +netns diff --git a/tools/testing/selftests/nsfs/Makefile b/tools/testing/selftests/nsfs/Makefile index dd9bd50b7b93..93793cdb5a7c 100644 --- a/tools/testing/selftests/nsfs/Makefile +++ b/tools/testing/selftests/nsfs/Makefile @@ -1,5 +1,5 @@ # SPDX-License-Identifier: GPL-2.0-only -TEST_GEN_PROGS := owner pidns +TEST_GEN_PROGS := owner pidns netns
CFLAGS := -Wall -Werror
diff --git a/tools/testing/selftests/nsfs/netns.c b/tools/testing/selftests/nsfs/netns.c new file mode 100644 index 000000000000..8ab862667b45 --- /dev/null +++ b/tools/testing/selftests/nsfs/netns.c @@ -0,0 +1,57 @@ +// SPDX-License-Identifier: GPL-2.0 +#define _GNU_SOURCE +#include <sched.h> +#include <unistd.h> +#include <stdio.h> +#include <stdlib.h> +#include <stdint.h> +#include <fcntl.h> +#include <sys/ioctl.h> + +#define NSIO 0xb7 +#define NS_GET_COOKIE _IO(NSIO, 0x5) + +#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; + char path[128]; + int ns; + + snprintf(path, sizeof(path), "/proc/%d/ns/net", getpid()); + ns = open(path, O_RDONLY); + if (ns < 0) + return pr_err("Unable to open %s", path); + + if (ioctl(ns, NS_GET_COOKIE, &cookie1)) + return pr_err("Unable to get first namespace cookie"); + + if (!cookie1) + return pr_err("NS_GET_COOKIE returned zero first cookie"); + + close(ns); + if (unshare(CLONE_NEWNET)) + return pr_err("unshare"); + + ns = open(path, O_RDONLY); + if (ns < 0) + return pr_err("Unable to open %s", path); + + if (ioctl(ns, NS_GET_COOKIE, &cookie2)) + return pr_err("Unable to get second namespace cookie"); + + if (!cookie2) + return pr_err("NS_GET_COOKIE returned zero second cookie"); + + if (cookie1 == cookie2) + return pr_err("NS_GET_COOKIE returned identical cookies for distinct ns"); + + close(ns); + return 0; +}