From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8FBD0365D3F; Wed, 29 Oct 2025 12:26:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761740768; cv=none; b=NptA8RIUQCxa6B8oaMOhBeqbKGka1k96ccWXfF+mysG3W/1mv2S7/bGQVIxo7gdRXZQp020P6woQZZcPwWce+iZG/KFaCH/0Gq/Zh5SVEqM/zWia8FgJ8UwXDjTeMrmKLQ0oZ9sJWv3mDOMspG/M5pmaihFGVPFr0Pe3xHtNAyE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761740768; c=relaxed/simple; bh=sKXDidGiOR1H5xWVrgVg4FOPuYvFiXWeY9Fffw5SXJg=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=jJPcXDNavjEZ0ylJ/6mKewiHg2iQuJD+Fh5Yb7H4t4bRxdWxiMfQaJkAaK5d6XGAE8IH2kjsmFE2du+pms7Mc3YrR0Aai8IK1Btu3cXKIoGWEXUcXGIWzL/SC9wqv3UDLaceVnC1dZshhIr3pLoJ8E5fnTiSAZ8FxyzsdBtPnmE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VCcLoj5F; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="VCcLoj5F" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C2929C4CEFD; Wed, 29 Oct 2025 12:26:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761740768; bh=sKXDidGiOR1H5xWVrgVg4FOPuYvFiXWeY9Fffw5SXJg=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=VCcLoj5F92WydhpUaExQybGECJpLCiE3ia9Sfn4lPRnUS8DTWKiYbdf8wsEkeSYiP jW2wDylgAbzIZg1O5jNdOJ26XRdxQSvyF5j5pmKhuvM8g5v58UngUZgpaDN7EcUyug kZWU4+emWFsWXiTOvVBrNU3vpiJwycyx5345G/C9VqMDGqBsHDco+jhvcuZIEwX+yV JYU22HAGxa/dUQ1aW7NvW6xiAtyLYyPra3XNH3zeQuaZKW67LvFzm1cffsZDzTbPRa 6azPxsK9RugreuGMJ+yhERkJBB2NK+G/4yR+sjJX7kpWnhcrQYPQ7/e7vMb4AkfCDN 4zz8JvKF5VhOQ== From: Christian Brauner Date: Wed, 29 Oct 2025 13:21:18 +0100 Subject: [PATCH v4 65/72] selftests/namespaces: eleventh inactive namespace resurrection test Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20251029-work-namespace-nstree-listns-v4-65-2e6f823ebdc0@kernel.org> References: <20251029-work-namespace-nstree-listns-v4-0-2e6f823ebdc0@kernel.org> In-Reply-To: <20251029-work-namespace-nstree-listns-v4-0-2e6f823ebdc0@kernel.org> To: linux-fsdevel@vger.kernel.org, Josef Bacik , Jeff Layton Cc: Jann Horn , Mike Yuan , =?utf-8?q?Zbigniew_J=C4=99drzejewski-Szmek?= , Lennart Poettering , Daan De Meyer , Aleksa Sarai , Amir Goldstein , Tejun Heo , Johannes Weiner , Thomas Gleixner , Alexander Viro , Jan Kara , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, bpf@vger.kernel.org, Eric Dumazet , Jakub Kicinski , netdev@vger.kernel.org, Arnd Bergmann , Christian Brauner X-Mailer: b4 0.15-dev-96507 X-Developer-Signature: v=1; a=openpgp-sha256; l=8469; i=brauner@kernel.org; h=from:subject:message-id; bh=sKXDidGiOR1H5xWVrgVg4FOPuYvFiXWeY9Fffw5SXJg=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMWQysU0Q0L54fu0O7xNum5+828pZZnXH5Jd6x9XOsKg8m V9Gbx3sOkpZGMS4GGTFFFkc2k3C5ZbzVGw2ytSAmcPKBDKEgYtTACaScJ/hf0LdLwYHbrmS2snx fbfD1reKnbebZmV3/M/8F68Zrk9W82P4pza7o7QqdOaUwnmKQeJ7uRY822cfEljntH7v/7nKK9i P8AAA X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Test combined listns() and file handle operations with socket-kept netns. Create a netns, keep it alive with a socket, verify it appears in listns(), then reopen it via file handle obtained from listns() entry. Signed-off-by: Christian Brauner --- .../testing/selftests/namespaces/siocgskns_test.c | 283 +++++++++++++++++++++ 1 file changed, 283 insertions(+) diff --git a/tools/testing/selftests/namespaces/siocgskns_test.c b/tools/testing/selftests/namespaces/siocgskns_test.c index a909232dba36..706049768d52 100644 --- a/tools/testing/selftests/namespaces/siocgskns_test.c +++ b/tools/testing/selftests/namespaces/siocgskns_test.c @@ -974,4 +974,287 @@ TEST(siocgskns_file_handle) free(handle); } +/* + * Test combined listns() and file handle operations with socket-kept netns. + * Create a netns, keep it alive with a socket, verify it appears in listns(), + * then reopen it via file handle obtained from listns() entry. + */ +TEST(siocgskns_listns_and_file_handle) +{ + int sock_fd, netns_fd, userns_fd, reopened_fd; + int ipc_sockets[2]; + pid_t pid; + int status; + struct stat st; + ino_t netns_ino; + __u64 netns_id, userns_id; + struct ns_id_req req = { + .size = sizeof(req), + .spare = 0, + .ns_id = 0, + .ns_type = CLONE_NEWNET | CLONE_NEWUSER, + .spare2 = 0, + .user_ns_id = 0, + }; + __u64 ns_ids[256]; + int ret, i; + bool found_netns = false, found_userns = false; + struct file_handle *handle; + struct nsfs_file_handle *nsfs_fh; + + /* Allocate file_handle structure for nsfs */ + handle = malloc(sizeof(struct file_handle) + sizeof(struct nsfs_file_handle)); + ASSERT_NE(handle, NULL); + handle->handle_bytes = sizeof(struct nsfs_file_handle); + handle->handle_type = FILEID_NSFS; + + EXPECT_EQ(socketpair(AF_LOCAL, SOCK_STREAM | SOCK_CLOEXEC, 0, ipc_sockets), 0); + + pid = fork(); + ASSERT_GE(pid, 0); + + if (pid == 0) { + /* Child: create new userns and netns with socket */ + close(ipc_sockets[0]); + + if (setup_userns() < 0) { + close(ipc_sockets[1]); + exit(1); + } + + if (unshare(CLONE_NEWNET) < 0) { + close(ipc_sockets[1]); + exit(1); + } + + sock_fd = socket(AF_INET, SOCK_DGRAM, 0); + if (sock_fd < 0) { + close(ipc_sockets[1]); + exit(1); + } + + /* Send socket FD to parent via SCM_RIGHTS */ + struct msghdr msg = {0}; + struct iovec iov = {0}; + char buf[1] = {'X'}; + char cmsg_buf[CMSG_SPACE(sizeof(int))]; + + iov.iov_base = buf; + iov.iov_len = 1; + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + msg.msg_control = cmsg_buf; + msg.msg_controllen = sizeof(cmsg_buf); + + struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg); + cmsg->cmsg_level = SOL_SOCKET; + cmsg->cmsg_type = SCM_RIGHTS; + cmsg->cmsg_len = CMSG_LEN(sizeof(int)); + memcpy(CMSG_DATA(cmsg), &sock_fd, sizeof(int)); + + if (sendmsg(ipc_sockets[1], &msg, 0) < 0) { + close(sock_fd); + close(ipc_sockets[1]); + exit(1); + } + + close(sock_fd); + close(ipc_sockets[1]); + exit(0); + } + + /* Parent: receive socket FD */ + close(ipc_sockets[1]); + + struct msghdr msg = {0}; + struct iovec iov = {0}; + char buf[1]; + char cmsg_buf[CMSG_SPACE(sizeof(int))]; + + iov.iov_base = buf; + iov.iov_len = 1; + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + msg.msg_control = cmsg_buf; + msg.msg_controllen = sizeof(cmsg_buf); + + ssize_t n = recvmsg(ipc_sockets[0], &msg, 0); + close(ipc_sockets[0]); + ASSERT_EQ(n, 1); + + struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg); + ASSERT_NE(cmsg, NULL); + memcpy(&sock_fd, CMSG_DATA(cmsg), sizeof(int)); + + /* Wait for child to exit */ + waitpid(pid, &status, 0); + ASSERT_TRUE(WIFEXITED(status)); + ASSERT_EQ(WEXITSTATUS(status), 0); + + /* Get network namespace from socket */ + netns_fd = ioctl(sock_fd, SIOCGSKNS); + if (netns_fd < 0) { + free(handle); + close(sock_fd); + if (errno == ENOTTY || errno == EINVAL) + SKIP(return, "SIOCGSKNS not supported"); + ASSERT_GE(netns_fd, 0); + } + + ASSERT_EQ(fstat(netns_fd, &st), 0); + netns_ino = st.st_ino; + + /* Get namespace ID */ + ret = ioctl(netns_fd, NS_GET_ID, &netns_id); + if (ret < 0) { + free(handle); + close(sock_fd); + close(netns_fd); + if (errno == ENOTTY || errno == EINVAL) + SKIP(return, "NS_GET_ID not supported"); + ASSERT_EQ(ret, 0); + } + + /* Get owner user namespace */ + userns_fd = ioctl(netns_fd, NS_GET_USERNS); + if (userns_fd < 0) { + free(handle); + close(sock_fd); + close(netns_fd); + if (errno == ENOTTY || errno == EINVAL) + SKIP(return, "NS_GET_USERNS not supported"); + ASSERT_GE(userns_fd, 0); + } + + /* Get owner namespace ID */ + ret = ioctl(userns_fd, NS_GET_ID, &userns_id); + if (ret < 0) { + close(userns_fd); + free(handle); + close(sock_fd); + close(netns_fd); + ASSERT_EQ(ret, 0); + } + close(userns_fd); + + TH_LOG("Testing netns %lu (id=%llu) owned by userns id=%llu", netns_ino, netns_id, userns_id); + + /* Verify namespace appears in listns() */ + ret = sys_listns(&req, ns_ids, ARRAY_SIZE(ns_ids), 0); + if (ret < 0) { + free(handle); + close(sock_fd); + close(netns_fd); + if (errno == ENOSYS) + SKIP(return, "listns() not supported"); + TH_LOG("listns failed: %s", strerror(errno)); + ASSERT_GE(ret, 0); + } + + found_netns = false; + found_userns = false; + for (i = 0; i < ret; i++) { + if (ns_ids[i] == netns_id) + found_netns = true; + if (ns_ids[i] == userns_id) + found_userns = true; + } + ASSERT_TRUE(found_netns); + ASSERT_TRUE(found_userns); + TH_LOG("Found netns %llu in listns() output", netns_id); + + /* Construct file handle from namespace ID */ + nsfs_fh = (struct nsfs_file_handle *)handle->f_handle; + nsfs_fh->ns_id = netns_id; + nsfs_fh->ns_type = 0; + nsfs_fh->ns_inum = 0; + + reopened_fd = open_by_handle_at(FD_NSFS_ROOT, handle, O_RDONLY); + if (reopened_fd < 0) { + free(handle); + close(sock_fd); + if (errno == EOPNOTSUPP || errno == ENOSYS || errno == EBADF) + SKIP(return, "open_by_handle_at with FD_NSFS_ROOT not supported"); + TH_LOG("open_by_handle_at failed: %s", strerror(errno)); + ASSERT_GE(reopened_fd, 0); + } + + struct stat reopened_st; + ASSERT_EQ(fstat(reopened_fd, &reopened_st), 0); + ASSERT_EQ(reopened_st.st_ino, netns_ino); + + TH_LOG("Successfully reopened netns %lu via file handle (socket-kept)", netns_ino); + + close(reopened_fd); + close(netns_fd); + + /* Try to reopen via file handle - should fail since namespace is now inactive */ + reopened_fd = open_by_handle_at(FD_NSFS_ROOT, handle, O_RDONLY); + ASSERT_LT(reopened_fd, 0); + TH_LOG("Correctly failed to reopen inactive netns: %s", strerror(errno)); + + /* Get network namespace from socket */ + netns_fd = ioctl(sock_fd, SIOCGSKNS); + if (netns_fd < 0) { + free(handle); + close(sock_fd); + if (errno == ENOTTY || errno == EINVAL) + SKIP(return, "SIOCGSKNS not supported"); + ASSERT_GE(netns_fd, 0); + } + + /* Verify namespace appears in listns() */ + ret = sys_listns(&req, ns_ids, ARRAY_SIZE(ns_ids), 0); + if (ret < 0) { + free(handle); + close(sock_fd); + close(netns_fd); + if (errno == ENOSYS) + SKIP(return, "listns() not supported"); + TH_LOG("listns failed: %s", strerror(errno)); + ASSERT_GE(ret, 0); + } + + found_netns = false; + found_userns = false; + for (i = 0; i < ret; i++) { + if (ns_ids[i] == netns_id) + found_netns = true; + if (ns_ids[i] == userns_id) + found_userns = true; + } + ASSERT_TRUE(found_netns); + ASSERT_TRUE(found_userns); + TH_LOG("Found netns %llu in listns() output", netns_id); + + close(netns_fd); + + /* Verify namespace appears in listns() */ + ret = sys_listns(&req, ns_ids, ARRAY_SIZE(ns_ids), 0); + if (ret < 0) { + free(handle); + close(sock_fd); + close(netns_fd); + if (errno == ENOSYS) + SKIP(return, "listns() not supported"); + TH_LOG("listns failed: %s", strerror(errno)); + ASSERT_GE(ret, 0); + } + + found_netns = false; + found_userns = false; + for (i = 0; i < ret; i++) { + if (ns_ids[i] == netns_id) + found_netns = true; + if (ns_ids[i] == userns_id) + found_userns = true; + } + ASSERT_FALSE(found_netns); + ASSERT_FALSE(found_userns); + TH_LOG("Netns %llu correctly disappeared from listns() after socket closed", netns_id); + + close(sock_fd); + free(handle); +} + TEST_HARNESS_MAIN -- 2.47.3