Hi, This new patch series brings some improvements and add new tests: Use smaller userspace structures (attributes) to save space, and check at built time that every attribute don't contain hole and are 8-bits aligned. Allow enforcement of empty ruleset, which enables deny-all policies (useful for strict sandboxes). I found that UML may not keep the same internal struct inode for an open file. Because the Landlock filesystem access-control relies on internal kernel states, special architectures such as UML can't support Landlock. Add a new ARCH_EPHEMERAL_STATES to identify such architectures. Add a size_attr_features field to struct landlock_attr_features for self-introspection Switch syscall attribute pointer and size arguments to follow similar syscalls argument order (e.g. bpf, clone3, openat2). The SLOC count is 1288 for security/landlock/ and 1740 for tools/testing/selftest/landlock/ . Test coverage for security/landlock/ is 93.6% of lines. The code not covered only deals with internal kernel errors (e.g. memory allocation) and race conditions. The compiled documentation is available here: https://landlock.io/linux-doc/landlock-v17/security/landlock/index.html This series can be applied on top of v5.7-rc5. This can be tested with CONFIG_SECURITY_LANDLOCK and CONFIG_SAMPLE_LANDLOCK. This patch series can be found in a Git repository here: https://github.com/landlock-lsm/linux/commits/landlock-v17 I would really appreciate constructive comments on this patch series. # Landlock LSM The goal of Landlock is to enable to restrict ambient rights (e.g. global filesystem access) for a set of processes. Because Landlock is a stackable LSM [2], it makes possible to create safe security sandboxes as new security layers in addition to the existing system-wide access-controls. This kind of sandbox is expected to help mitigate the security impact of bugs or unexpected/malicious behaviors in user-space applications. Landlock empowers any process, including unprivileged ones, to securely restrict themselves. Landlock is inspired by seccomp-bpf but instead of filtering syscalls and their raw arguments, a Landlock rule can restrict the use of kernel objects like file hierarchies, according to the kernel semantic. Landlock also takes inspiration from other OS sandbox mechanisms: XNU Sandbox, FreeBSD Capsicum or OpenBSD Pledge/Unveil. Previous version: https://lore.kernel.org/lkml/20200416103955.145757-1-mic@xxxxxxxxxxx/ [1] https://lore.kernel.org/lkml/e07fe473-1801-01cc-12ae-b3167f95250e@xxxxxxxxxxx/ [2] https://lore.kernel.org/lkml/50db058a-7dde-441b-a7f9-f6837fe8b69f@xxxxxxxxxxxxxxxx/ Regards, Mickaël Salaün (10): landlock: Add object management landlock: Add ruleset and domain management landlock: Set up the security framework and manage credentials landlock: Add ptrace restrictions fs,landlock: Support filesystem access-control landlock: Add syscall implementation arch: Wire up landlock() syscall selftests/landlock: Add initial tests samples/landlock: Add a sandbox manager example landlock: Add user and kernel documentation Documentation/security/index.rst | 1 + Documentation/security/landlock/index.rst | 18 + Documentation/security/landlock/kernel.rst | 69 + Documentation/security/landlock/user.rst | 268 +++ MAINTAINERS | 12 + arch/Kconfig | 7 + arch/alpha/kernel/syscalls/syscall.tbl | 1 + arch/arm/tools/syscall.tbl | 1 + arch/arm64/include/asm/unistd.h | 2 +- arch/arm64/include/asm/unistd32.h | 2 + arch/ia64/kernel/syscalls/syscall.tbl | 1 + arch/m68k/kernel/syscalls/syscall.tbl | 1 + arch/microblaze/kernel/syscalls/syscall.tbl | 1 + arch/mips/kernel/syscalls/syscall_n32.tbl | 1 + arch/mips/kernel/syscalls/syscall_n64.tbl | 1 + arch/mips/kernel/syscalls/syscall_o32.tbl | 1 + arch/parisc/kernel/syscalls/syscall.tbl | 1 + arch/powerpc/kernel/syscalls/syscall.tbl | 1 + arch/s390/kernel/syscalls/syscall.tbl | 1 + arch/sh/kernel/syscalls/syscall.tbl | 1 + arch/sparc/kernel/syscalls/syscall.tbl | 1 + arch/um/Kconfig | 1 + arch/x86/entry/syscalls/syscall_32.tbl | 1 + arch/x86/entry/syscalls/syscall_64.tbl | 1 + arch/xtensa/kernel/syscalls/syscall.tbl | 1 + fs/super.c | 2 + include/linux/fs.h | 5 + include/linux/landlock.h | 22 + include/linux/syscalls.h | 3 + include/uapi/asm-generic/unistd.h | 4 +- include/uapi/linux/landlock.h | 302 +++ kernel/sys_ni.c | 3 + samples/Kconfig | 7 + samples/Makefile | 1 + samples/landlock/.gitignore | 1 + samples/landlock/Makefile | 15 + samples/landlock/sandboxer.c | 228 +++ security/Kconfig | 11 +- security/Makefile | 2 + security/landlock/Kconfig | 18 + security/landlock/Makefile | 4 + security/landlock/common.h | 20 + security/landlock/cred.c | 46 + security/landlock/cred.h | 58 + security/landlock/fs.c | 601 ++++++ security/landlock/fs.h | 42 + security/landlock/object.c | 66 + security/landlock/object.h | 91 + security/landlock/ptrace.c | 120 ++ security/landlock/ptrace.h | 14 + security/landlock/ruleset.c | 342 ++++ security/landlock/ruleset.h | 161 ++ security/landlock/setup.c | 39 + security/landlock/setup.h | 18 + security/landlock/syscall.c | 532 +++++ tools/testing/selftests/Makefile | 1 + tools/testing/selftests/landlock/.gitignore | 2 + tools/testing/selftests/landlock/Makefile | 29 + tools/testing/selftests/landlock/base_test.c | 170 ++ tools/testing/selftests/landlock/common.h | 108 + tools/testing/selftests/landlock/config | 5 + tools/testing/selftests/landlock/fs_test.c | 1729 +++++++++++++++++ .../testing/selftests/landlock/ptrace_test.c | 293 +++ tools/testing/selftests/landlock/true.c | 5 + 64 files changed, 5509 insertions(+), 7 deletions(-) create mode 100644 Documentation/security/landlock/index.rst create mode 100644 Documentation/security/landlock/kernel.rst create mode 100644 Documentation/security/landlock/user.rst create mode 100644 include/linux/landlock.h create mode 100644 include/uapi/linux/landlock.h create mode 100644 samples/landlock/.gitignore create mode 100644 samples/landlock/Makefile create mode 100644 samples/landlock/sandboxer.c create mode 100644 security/landlock/Kconfig create mode 100644 security/landlock/Makefile create mode 100644 security/landlock/common.h create mode 100644 security/landlock/cred.c create mode 100644 security/landlock/cred.h create mode 100644 security/landlock/fs.c create mode 100644 security/landlock/fs.h create mode 100644 security/landlock/object.c create mode 100644 security/landlock/object.h create mode 100644 security/landlock/ptrace.c create mode 100644 security/landlock/ptrace.h create mode 100644 security/landlock/ruleset.c create mode 100644 security/landlock/ruleset.h create mode 100644 security/landlock/setup.c create mode 100644 security/landlock/setup.h create mode 100644 security/landlock/syscall.c create mode 100644 tools/testing/selftests/landlock/.gitignore create mode 100644 tools/testing/selftests/landlock/Makefile create mode 100644 tools/testing/selftests/landlock/base_test.c create mode 100644 tools/testing/selftests/landlock/common.h create mode 100644 tools/testing/selftests/landlock/config create mode 100644 tools/testing/selftests/landlock/fs_test.c create mode 100644 tools/testing/selftests/landlock/ptrace_test.c create mode 100644 tools/testing/selftests/landlock/true.c -- 2.26.2
