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Gunnarsson" To: Christian Brauner , Alexander Viro , Paul Moore , Serge Hallyn , Kees Cook , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: Jan Kara , James Morris , Simon Horman , Jonathan Corbet , Shuah Khan , Randy Dunlap , Jann Horn , "=?UTF-8?q?G=C3=BCnther=20Noack?=" , KP Singh , Jonathan Calmels , Casey Schaufler , linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org, linux-api@vger.kernel.org, containers@lists.linux.dev, netdev@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, "Hallgrimur H. Gunnarsson" Content-Type: text/plain; charset="UTF-8" Add tests for the NS_USER_GET_INFO ioctl to verify user namespace capability bounding set inspection and validate error paths. Signed-off-by: Hallgrimur H. Gunnarsson --- .../selftests/filesystems/nsfs/.gitignore | 1 + .../selftests/filesystems/nsfs/Makefile | 4 +- .../selftests/filesystems/nsfs/userns.c | 120 ++++++++++++++++++ 3 files changed, 123 insertions(+), 2 deletions(-) create mode 100644 tools/testing/selftests/filesystems/nsfs/userns.c diff --git a/tools/testing/selftests/filesystems/nsfs/.gitignore b/tools/testing/selftests/filesystems/nsfs/.gitignore index 92a8249006d1..b0a59f5d49fc 100644 --- a/tools/testing/selftests/filesystems/nsfs/.gitignore +++ b/tools/testing/selftests/filesystems/nsfs/.gitignore @@ -1,4 +1,5 @@ # SPDX-License-Identifier: GPL-2.0-only owner pidns +userns iterate_mntns diff --git a/tools/testing/selftests/filesystems/nsfs/Makefile b/tools/testing/selftests/filesystems/nsfs/Makefile index 231aaa7dfd95..9408d7948621 100644 --- a/tools/testing/selftests/filesystems/nsfs/Makefile +++ b/tools/testing/selftests/filesystems/nsfs/Makefile @@ -1,6 +1,6 @@ # SPDX-License-Identifier: GPL-2.0-only -TEST_GEN_PROGS := owner pidns iterate_mntns +TEST_GEN_PROGS := owner pidns iterate_mntns userns -CFLAGS := -Wall -Werror +CFLAGS += -Wall -Werror $(KHDR_INCLUDES) include ../../lib.mk diff --git a/tools/testing/selftests/filesystems/nsfs/userns.c b/tools/testing/selftests/filesystems/nsfs/userns.c new file mode 100644 index 000000000000..70661a495afc --- /dev/null +++ b/tools/testing/selftests/filesystems/nsfs/userns.c @@ -0,0 +1,120 @@ +// SPDX-License-Identifier: GPL-2.0 +#define _GNU_SOURCE + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../../clone3/clone3_selftests.h" +#include "../../kselftest_harness.h" + +TEST(user_get_info_self) +{ + struct user_ns_info info = {}; + int fd; + + fd = open("/proc/self/ns/user", O_RDONLY | O_CLOEXEC); + ASSERT_GE(fd, 0) { + TH_LOG("Failed to open /proc/self/ns/user: %m"); + } + + ASSERT_EQ(0, ioctl(fd, NS_USER_GET_INFO, &info)) { + TH_LOG("ioctl(NS_USER_GET_INFO) failed on self: %m"); + } + close(fd); + + EXPECT_EQ(USER_NS_INFO_SIZE_VER0, info.size); + EXPECT_EQ(0, info.spare); + EXPECT_NE(0ULL, info.cap_bset); +} + +TEST(user_get_info_restricted_bset) +{ + struct __clone_args args = { + .flags = CLONE_NEWUSER | CLONE_NEWUSER_BSET, + .exit_signal = SIGCHLD, + .cap_bset = 0, + }; + int status; + pid_t pid; + + pid = sys_clone3(&args, sizeof(args)); + ASSERT_GE(pid, 0); + + if (pid == 0) { + struct user_ns_info info = {}; + int fd; + + fd = open("/proc/self/ns/user", O_RDONLY | O_CLOEXEC); + if (fd < 0) + _exit(1); + + if (ioctl(fd, NS_USER_GET_INFO, &info) != 0) { + close(fd); + _exit(2); + } + close(fd); + + if (info.cap_bset != 0) + _exit(3); + + _exit(0); + } + + ASSERT_EQ(pid, waitpid(pid, &status, 0)); + ASSERT_TRUE(WIFEXITED(status)); + EXPECT_EQ(0, WEXITSTATUS(status)); +} + +TEST(user_get_info_invalid_ns_type) +{ + struct user_ns_info info = {}; + int mntns_fd; + + mntns_fd = open("/proc/self/ns/mnt", O_RDONLY | O_CLOEXEC); + ASSERT_GE(mntns_fd, 0) { + TH_LOG("Failed to open /proc/self/ns/mnt: %m"); + } + + EXPECT_EQ(-1, ioctl(mntns_fd, NS_USER_GET_INFO, &info)); + EXPECT_EQ(EINVAL, errno); + + close(mntns_fd); +} + +TEST(user_get_info_buffer_too_small) +{ + __u32 small_buf = 0; + int fd; + + fd = open("/proc/self/ns/user", O_RDONLY | O_CLOEXEC); + ASSERT_GE(fd, 0); + + /* Encode a buffer size smaller than USER_NS_INFO_SIZE_VER0 (4B vs 16B) */ + EXPECT_EQ(-1, ioctl(fd, _IOR(NSIO, 14, __u32), &small_buf)); + + close(fd); +} + +TEST(user_get_info_null_arg) +{ + int fd; + + fd = open("/proc/self/ns/user", O_RDONLY | O_CLOEXEC); + ASSERT_GE(fd, 0); + + EXPECT_EQ(-1, ioctl(fd, NS_USER_GET_INFO, NULL)); + EXPECT_EQ(EINVAL, errno); + + close(fd); +} + +TEST_HARNESS_MAIN -- 2.56.0.313.g2479322e68-goog