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 E1D40346E60; Wed, 29 Oct 2025 12:22:50 +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=1761740571; cv=none; b=naLUjtdDr8KRvfiI3OJ3tvcu1YInYak73zuzPTym6UDRy7o8q7Jk4rUkQL4B1xuO9YcF6rILSV17KR70mKOton83buU+Tzh0C6Gm+lO3sqN5e6jYZWXfIblS4VID1/0j5c0BEWz39wxeAdbcqSfGNq3NJXl5mqx1F7J7vnQfQ7U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761740571; c=relaxed/simple; bh=e8EI0iOiQx8fHK9+00tBtoOgGlNpcvVChJMa2f3XulI=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=MhwSHViMOVhxFGdNFdxV9LUX62ylYdk7D31qEQ/vuj8YXuMjhEWv2ZHb8HjJpHJITSjCfhdqn/5EK+Paz6jJJbwBcRoYmxajinE0OpbydmqjyD4UzH6m1vvsfzWe4scroLueWZmqv984JENSg7F4hkoRlwfERtLNg4sZVEdOMA4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=sCHsGA/4; 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="sCHsGA/4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0CE57C4CEF7; Wed, 29 Oct 2025 12:22:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761740570; bh=e8EI0iOiQx8fHK9+00tBtoOgGlNpcvVChJMa2f3XulI=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=sCHsGA/4hrBYx/I2LULBDsifN8HT60yBLZGQk+tlxDNdDIXbCglZjwwMZxAKawZTt M4qjzLAD3cO8tb7i/83H3wLHRHWiBG909EciDRAucGuuin9C+TM8NXxmgXNqlzuujm dlcJx1Ng4Zxef7Abz6AEzIGyhv1qeXLSzq+xzRVxBwJTkRmRtvSszigruN17Xe4hvR iJrlg79bqytz1GHdMzctqkJwmxJC3LGplKNxgkD8FFogq9UJWic77cNMQRxalmOr+7 mFXDJDY4fguWUaYq4Qfm++eLm4XKKo+NCxKQueJVxMwZBkXPsnXelFHw4jIF3aBppr K48kcsHNJZZiA== From: Christian Brauner Date: Wed, 29 Oct 2025 13:20:39 +0100 Subject: [PATCH v4 26/72] selftests/namespaces: fourth active reference count tests 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-v4-26-2e6f823ebdc0@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=2891; i=brauner@kernel.org; h=from:subject:message-id; bh=e8EI0iOiQx8fHK9+00tBtoOgGlNpcvVChJMa2f3XulI=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMWQysfUKvHvrtuZkvNh919X+T/ee2LGmKKZX7dmpMEfGt M0P8goCO0pZGMS4GGTFFFkc2k3C5ZbzVGw2ytSAmcPKBDKEgYtTACbS7czI8Mf/pUHcSkeZaTVS HwXazpTH3Hpx78KJ+qKdn3TsbRhXVjMytK63jGzc9clz7fRIq//Bxfu3d2bf3p//l60hxH5Zx4V 2ZgA= X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Test user namespace active ref tracking via credential lifecycle. Signed-off-by: Christian Brauner --- .../selftests/namespaces/ns_active_ref_test.c | 90 ++++++++++++++++++++++ 1 file changed, 90 insertions(+) diff --git a/tools/testing/selftests/namespaces/ns_active_ref_test.c b/tools/testing/selftests/namespaces/ns_active_ref_test.c index c2e34de7a3a9..396066e641da 100644 --- a/tools/testing/selftests/namespaces/ns_active_ref_test.c +++ b/tools/testing/selftests/namespaces/ns_active_ref_test.c @@ -276,4 +276,94 @@ TEST(ns_active_with_multiple_processes) ASSERT_TRUE(WIFEXITED(status)); } +/* + * Test user namespace active ref tracking via credential lifecycle + */ +TEST(userns_active_ref_lifecycle) +{ + struct file_handle *handle; + int mount_id; + int ret; + int fd; + int pipefd[2]; + pid_t pid; + int status; + char buf[sizeof(*handle) + MAX_HANDLE_SZ]; + + ASSERT_EQ(pipe(pipefd), 0); + + pid = fork(); + ASSERT_GE(pid, 0); + + if (pid == 0) { + /* Child process */ + close(pipefd[0]); + + /* Create new user namespace */ + ret = unshare(CLONE_NEWUSER); + if (ret < 0) { + close(pipefd[1]); + exit(1); + } + + /* Set up uid/gid mappings */ + int uid_map_fd = open("/proc/self/uid_map", O_WRONLY); + int gid_map_fd = open("/proc/self/gid_map", O_WRONLY); + int setgroups_fd = open("/proc/self/setgroups", O_WRONLY); + + if (uid_map_fd >= 0 && gid_map_fd >= 0 && setgroups_fd >= 0) { + write(setgroups_fd, "deny", 4); + close(setgroups_fd); + + char mapping[64]; + snprintf(mapping, sizeof(mapping), "0 %d 1", getuid()); + write(uid_map_fd, mapping, strlen(mapping)); + close(uid_map_fd); + + snprintf(mapping, sizeof(mapping), "0 %d 1", getgid()); + write(gid_map_fd, mapping, strlen(mapping)); + close(gid_map_fd); + } + + /* Get file handle */ + fd = open("/proc/self/ns/user", O_RDONLY); + if (fd < 0) { + close(pipefd[1]); + exit(1); + } + + handle = (struct file_handle *)buf; + handle->handle_bytes = MAX_HANDLE_SZ; + ret = name_to_handle_at(fd, "", handle, &mount_id, AT_EMPTY_PATH); + close(fd); + + if (ret < 0) { + close(pipefd[1]); + exit(1); + } + + /* Send handle to parent */ + write(pipefd[1], buf, sizeof(*handle) + handle->handle_bytes); + close(pipefd[1]); + exit(0); + } + + /* Parent */ + close(pipefd[1]); + ret = read(pipefd[0], buf, sizeof(buf)); + close(pipefd[0]); + + waitpid(pid, &status, 0); + ASSERT_TRUE(WIFEXITED(status)); + ASSERT_EQ(WEXITSTATUS(status), 0); + + ASSERT_GT(ret, 0); + handle = (struct file_handle *)buf; + + /* Namespace should be inactive after all tasks exit */ + fd = open_by_handle_at(FD_NSFS_ROOT, handle, O_RDONLY); + ASSERT_LT(fd, 0); + ASSERT_TRUE(errno == ENOENT || errno == ESTALE); +} + TEST_HARNESS_MAIN -- 2.47.3