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 09946318142; Fri, 24 Oct 2025 10:58:40 +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=1761303520; cv=none; b=X9U9keIh+acJBzDGFt59q0BkuYHbaM1OfLpFIuw+Bd6hJm9vD/tT8BgeI14XBo4vIOq5U/IsZTAm7ChMe3LJZI3e+m7Co19ZmqsokEtBBMR71y5K4S8ezVychSiv8TAuEb6BpT23VXbgVljW+5hf5NhFUHzB1UlKOX/TzolDy7M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761303520; c=relaxed/simple; bh=2GRkF4aTvddGMSpKeYnAxQf+2i+z67SQVbcHcw3mqCk=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=buWxFCbOuhGz1UvUYbCmD4koDJc7X1hvNqlKwvCLcGZHGUKaJ96C14/N2I0HrSiLAf35Uz3uuKrMS//Aw7KTueb6C/aTky2bKl48ip9wTnwKk8zXt8R6QJMDGJD1LolQ0TmAkZeYrvaFl4ynG3HQPvnfo/hsrJXB74IGiXqC+XI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=dlgs5ul2; 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="dlgs5ul2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5E0D2C4CEF5; Fri, 24 Oct 2025 10:58:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761303519; bh=2GRkF4aTvddGMSpKeYnAxQf+2i+z67SQVbcHcw3mqCk=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=dlgs5ul21HqMAKH0vzw3669fuZ2kyoxwus8rZOBODOyp0ZYU26c61rXzj+1iUcvCS T/XWXBWCWAiPP+ET/40hezlm3pTRZU5uQUexTRTWaCHKJNdGNnDmuNBDE3WFJ2DXPs brAlgHPNTMdVhM8wJqm46eiQDZ7xJv7aICoHrieTRqhGdhdoKrUTOLjuu5MRn/sE+r BpetiXzKh30mkFn6Vq9LsHQG+T2/82hwV0nmx8sr8rMhu15TsRArogh8MmV+ovcGse n8iEPAfOJL3U1EVsitGUnSk+87j9gR99kc1afAOcfQOAzOW3G4PSrU5MDEfNTT2WdU NQ/nyLnNTOswg== From: Christian Brauner Date: Fri, 24 Oct 2025 12:53:30 +0200 Subject: [PATCH v3 61/70] selftests/namespaces: ninth inactive namespace resurrection test Precedence: bulk X-Mailing-List: cgroups@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: <20251024-work-namespace-nstree-listns-v3-61-b6241981b72b@kernel.org> References: <20251024-work-namespace-nstree-listns-v3-0-b6241981b72b@kernel.org> In-Reply-To: <20251024-work-namespace-nstree-listns-v3-0-b6241981b72b@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=5894; i=brauner@kernel.org; h=from:subject:message-id; bh=2GRkF4aTvddGMSpKeYnAxQf+2i+z67SQVbcHcw3mqCk=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMWT8jmpf/246m7z+lg5H+4bNxy+8PHd4uU+lfeW9HS/3V 4nuTngzvaOUhUGMi0FWTJHFod0kXG45T8Vmo0wNmDmsTCBDGLg4BWAi0tWMDM8Z4296n3+wY63b rPUlrnNXT2pXDf/u4C/MuOLAzjmtE08w/I81/7uvZnZPhmTOQt0nCgvTj0aKFN9nuxp4iGcKe/I 5YSYA X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Test that socket-kept netns appears in listns() output. Verify that a network namespace kept alive by a socket FD appears in listns() output even after the creating process exits, and that it disappears when the socket is closed. Signed-off-by: Christian Brauner --- .../testing/selftests/namespaces/siocgskns_test.c | 203 +++++++++++++++++++++ 1 file changed, 203 insertions(+) diff --git a/tools/testing/selftests/namespaces/siocgskns_test.c b/tools/testing/selftests/namespaces/siocgskns_test.c index 47c1524a8648..98f6a0e1b9dd 100644 --- a/tools/testing/selftests/namespaces/siocgskns_test.c +++ b/tools/testing/selftests/namespaces/siocgskns_test.c @@ -576,4 +576,207 @@ TEST(siocgskns_ipv6) close(current_netns_fd); } +/* + * Test that socket-kept netns appears in listns() output. + * Verify that a network namespace kept alive by a socket FD appears in + * listns() output even after the creating process exits, and that it + * disappears when the socket is closed. + */ +TEST(siocgskns_listns_visibility) +{ + int sock_fd, netns_fd, owner_fd; + int ipc_sockets[2]; + pid_t pid; + int status; + __u64 netns_id, owner_id; + struct ns_id_req req = { + .size = sizeof(req), + .spare = 0, + .ns_id = 0, + .ns_type = CLONE_NEWNET, + .spare2 = 0, + .user_ns_id = 0, + }; + __u64 ns_ids[256]; + int ret, i; + bool found_netns = false; + + 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 netns and socket */ + close(ipc_sockets[0]); + + 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) { + close(sock_fd); + if (errno == ENOTTY || errno == EINVAL) + SKIP(return, "SIOCGSKNS not supported"); + ASSERT_GE(netns_fd, 0); + } + + /* Get namespace ID */ + ret = ioctl(netns_fd, NS_GET_ID, &netns_id); + if (ret < 0) { + 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 */ + owner_fd = ioctl(netns_fd, NS_GET_USERNS); + if (owner_fd < 0) { + close(sock_fd); + close(netns_fd); + if (errno == ENOTTY || errno == EINVAL) + SKIP(return, "NS_GET_USERNS not supported"); + ASSERT_GE(owner_fd, 0); + } + + /* Get owner namespace ID */ + ret = ioctl(owner_fd, NS_GET_ID, &owner_id); + if (ret < 0) { + close(owner_fd); + close(sock_fd); + close(netns_fd); + ASSERT_EQ(ret, 0); + } + close(owner_fd); + + /* Namespace should appear in listns() output */ + ret = sys_listns(&req, ns_ids, ARRAY_SIZE(ns_ids), 0); + if (ret < 0) { + 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); + } + + /* Search for our network namespace in the list */ + for (i = 0; i < ret; i++) { + if (ns_ids[i] == netns_id) { + found_netns = true; + break; + } + } + + ASSERT_TRUE(found_netns); + TH_LOG("Found netns %llu in listns() output (kept alive by socket)", netns_id); + + /* Now verify with owner filtering */ + req.user_ns_id = owner_id; + found_netns = false; + + ret = sys_listns(&req, ns_ids, ARRAY_SIZE(ns_ids), 0); + ASSERT_GE(ret, 0); + + for (i = 0; i < ret; i++) { + if (ns_ids[i] == netns_id) { + found_netns = true; + break; + } + } + + ASSERT_TRUE(found_netns); + TH_LOG("Found netns %llu owned by userns %llu", netns_id, owner_id); + + /* Close socket - namespace should become inactive and disappear from listns() */ + close(sock_fd); + close(netns_fd); + + /* Verify it's no longer in listns() output */ + req.user_ns_id = 0; + found_netns = false; + + ret = sys_listns(&req, ns_ids, ARRAY_SIZE(ns_ids), 0); + ASSERT_GE(ret, 0); + + for (i = 0; i < ret; i++) { + if (ns_ids[i] == netns_id) { + found_netns = true; + break; + } + } + + ASSERT_FALSE(found_netns); + TH_LOG("Netns %llu correctly disappeared from listns() after socket closed", netns_id); +} + TEST_HARNESS_MAIN -- 2.47.3