From cb2c7d1a1776057c9a1f48ed1250d85e94d4850d Mon Sep 17 00:00:00 2001 From: Mickaël Salaün Date: Thu, 22 Apr 2021 17:41:17 +0200 Subject: landlock: Support filesystem access-control MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Using Landlock objects and ruleset, it is possible to tag inodes according to a process's domain. To enable an unprivileged process to express a file hierarchy, it first needs to open a directory (or a file) and pass this file descriptor to the kernel through landlock_add_rule(2). When checking if a file access request is allowed, we walk from the requested dentry to the real root, following the different mount layers. The access to each "tagged" inodes are collected according to their rule layer level, and ANDed to create access to the requested file hierarchy. This makes possible to identify a lot of files without tagging every inodes nor modifying the filesystem, while still following the view and understanding the user has from the filesystem. Add a new ARCH_EPHEMERAL_INODES for UML because it currently does not keep the same struct inodes for the same inodes whereas these inodes are in use. This commit adds a minimal set of supported filesystem access-control which doesn't enable to restrict all file-related actions. This is the result of multiple discussions to minimize the code of Landlock to ease review. Thanks to the Landlock design, extending this access-control without breaking user space will not be a problem. Moreover, seccomp filters can be used to restrict the use of syscall families which may not be currently handled by Landlock. Cc: Al Viro Cc: Anton Ivanov Cc: James Morris Cc: Jann Horn Cc: Jeff Dike Cc: Kees Cook Cc: Richard Weinberger Cc: Serge E. Hallyn Signed-off-by: Mickaël Salaün Link: https://lore.kernel.org/r/20210422154123.13086-8-mic@digikod.net Signed-off-by: James Morris --- include/uapi/linux/landlock.h | 76 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 76 insertions(+) create mode 100644 include/uapi/linux/landlock.h (limited to 'include/uapi') diff --git a/include/uapi/linux/landlock.h b/include/uapi/linux/landlock.h new file mode 100644 index 000000000000..b1a81b5a8b86 --- /dev/null +++ b/include/uapi/linux/landlock.h @@ -0,0 +1,76 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* + * Landlock - User space API + * + * Copyright © 2017-2020 Mickaël Salaün + * Copyright © 2018-2020 ANSSI + */ + +#ifndef _UAPI_LINUX_LANDLOCK_H +#define _UAPI_LINUX_LANDLOCK_H + +/** + * DOC: fs_access + * + * A set of actions on kernel objects may be defined by an attribute (e.g. + * &struct landlock_path_beneath_attr) including a bitmask of access. + * + * Filesystem flags + * ~~~~~~~~~~~~~~~~ + * + * These flags enable to restrict a sandboxed process to a set of actions on + * files and directories. Files or directories opened before the sandboxing + * are not subject to these restrictions. + * + * A file can only receive these access rights: + * + * - %LANDLOCK_ACCESS_FS_EXECUTE: Execute a file. + * - %LANDLOCK_ACCESS_FS_WRITE_FILE: Open a file with write access. + * - %LANDLOCK_ACCESS_FS_READ_FILE: Open a file with read access. + * + * A directory can receive access rights related to files or directories. The + * following access right is applied to the directory itself, and the + * directories beneath it: + * + * - %LANDLOCK_ACCESS_FS_READ_DIR: Open a directory or list its content. + * + * However, the following access rights only apply to the content of a + * directory, not the directory itself: + * + * - %LANDLOCK_ACCESS_FS_REMOVE_DIR: Remove an empty directory or rename one. + * - %LANDLOCK_ACCESS_FS_REMOVE_FILE: Unlink (or rename) a file. + * - %LANDLOCK_ACCESS_FS_MAKE_CHAR: Create (or rename or link) a character + * device. + * - %LANDLOCK_ACCESS_FS_MAKE_DIR: Create (or rename) a directory. + * - %LANDLOCK_ACCESS_FS_MAKE_REG: Create (or rename or link) a regular file. + * - %LANDLOCK_ACCESS_FS_MAKE_SOCK: Create (or rename or link) a UNIX domain + * socket. + * - %LANDLOCK_ACCESS_FS_MAKE_FIFO: Create (or rename or link) a named pipe. + * - %LANDLOCK_ACCESS_FS_MAKE_BLOCK: Create (or rename or link) a block device. + * - %LANDLOCK_ACCESS_FS_MAKE_SYM: Create (or rename or link) a symbolic link. + * + * .. warning:: + * + * It is currently not possible to restrict some file-related actions + * accessible through these syscall families: :manpage:`chdir(2)`, + * :manpage:`truncate(2)`, :manpage:`stat(2)`, :manpage:`flock(2)`, + * :manpage:`chmod(2)`, :manpage:`chown(2)`, :manpage:`setxattr(2)`, + * :manpage:`utime(2)`, :manpage:`ioctl(2)`, :manpage:`fcntl(2)`, + * :manpage:`access(2)`. + * Future Landlock evolutions will enable to restrict them. + */ +#define LANDLOCK_ACCESS_FS_EXECUTE (1ULL << 0) +#define LANDLOCK_ACCESS_FS_WRITE_FILE (1ULL << 1) +#define LANDLOCK_ACCESS_FS_READ_FILE (1ULL << 2) +#define LANDLOCK_ACCESS_FS_READ_DIR (1ULL << 3) +#define LANDLOCK_ACCESS_FS_REMOVE_DIR (1ULL << 4) +#define LANDLOCK_ACCESS_FS_REMOVE_FILE (1ULL << 5) +#define LANDLOCK_ACCESS_FS_MAKE_CHAR (1ULL << 6) +#define LANDLOCK_ACCESS_FS_MAKE_DIR (1ULL << 7) +#define LANDLOCK_ACCESS_FS_MAKE_REG (1ULL << 8) +#define LANDLOCK_ACCESS_FS_MAKE_SOCK (1ULL << 9) +#define LANDLOCK_ACCESS_FS_MAKE_FIFO (1ULL << 10) +#define LANDLOCK_ACCESS_FS_MAKE_BLOCK (1ULL << 11) +#define LANDLOCK_ACCESS_FS_MAKE_SYM (1ULL << 12) + +#endif /* _UAPI_LINUX_LANDLOCK_H */ -- cgit v1.2.3 From a49f4f81cb48925e8d7cbd9e59068f516e984144 Mon Sep 17 00:00:00 2001 From: Mickaël Salaün Date: Thu, 22 Apr 2021 17:41:19 +0200 Subject: arch: Wire up Landlock syscalls MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Wire up the following system calls for all architectures: * landlock_create_ruleset(2) * landlock_add_rule(2) * landlock_restrict_self(2) Cc: Arnd Bergmann Cc: James Morris Cc: Jann Horn Cc: Kees Cook Cc: Serge E. Hallyn Signed-off-by: Mickaël Salaün Link: https://lore.kernel.org/r/20210422154123.13086-10-mic@digikod.net Signed-off-by: James Morris --- arch/alpha/kernel/syscalls/syscall.tbl | 3 +++ arch/arm/tools/syscall.tbl | 3 +++ arch/arm64/include/asm/unistd.h | 2 +- arch/arm64/include/asm/unistd32.h | 6 ++++++ arch/ia64/kernel/syscalls/syscall.tbl | 3 +++ arch/m68k/kernel/syscalls/syscall.tbl | 3 +++ arch/microblaze/kernel/syscalls/syscall.tbl | 3 +++ arch/mips/kernel/syscalls/syscall_n32.tbl | 3 +++ arch/mips/kernel/syscalls/syscall_n64.tbl | 3 +++ arch/mips/kernel/syscalls/syscall_o32.tbl | 3 +++ arch/parisc/kernel/syscalls/syscall.tbl | 3 +++ arch/powerpc/kernel/syscalls/syscall.tbl | 3 +++ arch/s390/kernel/syscalls/syscall.tbl | 3 +++ arch/sh/kernel/syscalls/syscall.tbl | 3 +++ arch/sparc/kernel/syscalls/syscall.tbl | 3 +++ arch/x86/entry/syscalls/syscall_32.tbl | 3 +++ arch/x86/entry/syscalls/syscall_64.tbl | 3 +++ arch/xtensa/kernel/syscalls/syscall.tbl | 3 +++ include/uapi/asm-generic/unistd.h | 8 +++++++- 19 files changed, 62 insertions(+), 2 deletions(-) (limited to 'include/uapi') diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl index 02f0244e005c..4240f21b10b3 100644 --- a/arch/alpha/kernel/syscalls/syscall.tbl +++ b/arch/alpha/kernel/syscalls/syscall.tbl @@ -482,3 +482,6 @@ 550 common process_madvise sys_process_madvise 551 common epoll_pwait2 sys_epoll_pwait2 552 common mount_setattr sys_mount_setattr +554 common landlock_create_ruleset sys_landlock_create_ruleset +555 common landlock_add_rule sys_landlock_add_rule +556 common landlock_restrict_self sys_landlock_restrict_self diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl index dcc1191291a2..161423a5d773 100644 --- a/arch/arm/tools/syscall.tbl +++ b/arch/arm/tools/syscall.tbl @@ -456,3 +456,6 @@ 440 common process_madvise sys_process_madvise 441 common epoll_pwait2 sys_epoll_pwait2 442 common mount_setattr sys_mount_setattr +444 common landlock_create_ruleset sys_landlock_create_ruleset +445 common landlock_add_rule sys_landlock_add_rule +446 common landlock_restrict_self sys_landlock_restrict_self diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h index 949788f5ba40..727bfc3be99b 100644 --- a/arch/arm64/include/asm/unistd.h +++ b/arch/arm64/include/asm/unistd.h @@ -38,7 +38,7 @@ #define __ARM_NR_compat_set_tls (__ARM_NR_COMPAT_BASE + 5) #define __ARM_NR_COMPAT_END (__ARM_NR_COMPAT_BASE + 0x800) -#define __NR_compat_syscalls 443 +#define __NR_compat_syscalls 447 #endif #define __ARCH_WANT_SYS_CLONE diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h index 3d874f624056..fdfe06bae3fc 100644 --- a/arch/arm64/include/asm/unistd32.h +++ b/arch/arm64/include/asm/unistd32.h @@ -893,6 +893,12 @@ __SYSCALL(__NR_process_madvise, sys_process_madvise) __SYSCALL(__NR_epoll_pwait2, compat_sys_epoll_pwait2) #define __NR_mount_setattr 442 __SYSCALL(__NR_mount_setattr, sys_mount_setattr) +#define __NR_landlock_create_ruleset 444 +__SYSCALL(__NR_landlock_create_ruleset, sys_landlock_create_ruleset) +#define __NR_landlock_add_rule 445 +__SYSCALL(__NR_landlock_add_rule, sys_landlock_add_rule) +#define __NR_landlock_restrict_self 446 +__SYSCALL(__NR_landlock_restrict_self, sys_landlock_restrict_self) /* * Please add new compat syscalls above this comment and update diff --git a/arch/ia64/kernel/syscalls/syscall.tbl b/arch/ia64/kernel/syscalls/syscall.tbl index d89231166e19..48dbbc95a01f 100644 --- a/arch/ia64/kernel/syscalls/syscall.tbl +++ b/arch/ia64/kernel/syscalls/syscall.tbl @@ -363,3 +363,6 @@ 440 common process_madvise sys_process_madvise 441 common epoll_pwait2 sys_epoll_pwait2 442 common mount_setattr sys_mount_setattr +444 common landlock_create_ruleset sys_landlock_create_ruleset +445 common landlock_add_rule sys_landlock_add_rule +446 common landlock_restrict_self sys_landlock_restrict_self diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl index 72bde6707dd3..595108bbbe42 100644 --- a/arch/m68k/kernel/syscalls/syscall.tbl +++ b/arch/m68k/kernel/syscalls/syscall.tbl @@ -442,3 +442,6 @@ 440 common process_madvise sys_process_madvise 441 common epoll_pwait2 sys_epoll_pwait2 442 common mount_setattr sys_mount_setattr +444 common landlock_create_ruleset sys_landlock_create_ruleset +445 common landlock_add_rule sys_landlock_add_rule +446 common landlock_restrict_self sys_landlock_restrict_self diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl index d603a5ec9338..db23d65871f9 100644 --- a/arch/microblaze/kernel/syscalls/syscall.tbl +++ b/arch/microblaze/kernel/syscalls/syscall.tbl @@ -448,3 +448,6 @@ 440 common process_madvise sys_process_madvise 441 common epoll_pwait2 sys_epoll_pwait2 442 common mount_setattr sys_mount_setattr +444 common landlock_create_ruleset sys_landlock_create_ruleset +445 common landlock_add_rule sys_landlock_add_rule +446 common landlock_restrict_self sys_landlock_restrict_self diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl index 8fd8c1790941..5028839225fa 100644 --- a/arch/mips/kernel/syscalls/syscall_n32.tbl +++ b/arch/mips/kernel/syscalls/syscall_n32.tbl @@ -381,3 +381,6 @@ 440 n32 process_madvise sys_process_madvise 441 n32 epoll_pwait2 compat_sys_epoll_pwait2 442 n32 mount_setattr sys_mount_setattr +444 n32 landlock_create_ruleset sys_landlock_create_ruleset +445 n32 landlock_add_rule sys_landlock_add_rule +446 n32 landlock_restrict_self sys_landlock_restrict_self diff --git a/arch/mips/kernel/syscalls/syscall_n64.tbl b/arch/mips/kernel/syscalls/syscall_n64.tbl index 169f21438065..ec9c68b75e23 100644 --- a/arch/mips/kernel/syscalls/syscall_n64.tbl +++ b/arch/mips/kernel/syscalls/syscall_n64.tbl @@ -357,3 +357,6 @@ 440 n64 process_madvise sys_process_madvise 441 n64 epoll_pwait2 sys_epoll_pwait2 442 n64 mount_setattr sys_mount_setattr +444 n64 landlock_create_ruleset sys_landlock_create_ruleset +445 n64 landlock_add_rule sys_landlock_add_rule +446 n64 landlock_restrict_self sys_landlock_restrict_self diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl index 090d29ca80ff..24afd33e3e49 100644 --- a/arch/mips/kernel/syscalls/syscall_o32.tbl +++ b/arch/mips/kernel/syscalls/syscall_o32.tbl @@ -430,3 +430,6 @@ 440 o32 process_madvise sys_process_madvise 441 o32 epoll_pwait2 sys_epoll_pwait2 compat_sys_epoll_pwait2 442 o32 mount_setattr sys_mount_setattr +444 o32 landlock_create_ruleset sys_landlock_create_ruleset +445 o32 landlock_add_rule sys_landlock_add_rule +446 o32 landlock_restrict_self sys_landlock_restrict_self diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl index 271a92519683..8ddd0b82d767 100644 --- a/arch/parisc/kernel/syscalls/syscall.tbl +++ b/arch/parisc/kernel/syscalls/syscall.tbl @@ -440,3 +440,6 @@ 440 common process_madvise sys_process_madvise 441 common epoll_pwait2 sys_epoll_pwait2 compat_sys_epoll_pwait2 442 common mount_setattr sys_mount_setattr +444 common landlock_create_ruleset sys_landlock_create_ruleset +445 common landlock_add_rule sys_landlock_add_rule +446 common landlock_restrict_self sys_landlock_restrict_self diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl index 0b2480cf3e47..02150894b1cf 100644 --- a/arch/powerpc/kernel/syscalls/syscall.tbl +++ b/arch/powerpc/kernel/syscalls/syscall.tbl @@ -522,3 +522,6 @@ 440 common process_madvise sys_process_madvise 441 common epoll_pwait2 sys_epoll_pwait2 compat_sys_epoll_pwait2 442 common mount_setattr sys_mount_setattr +444 common landlock_create_ruleset sys_landlock_create_ruleset +445 common landlock_add_rule sys_landlock_add_rule +446 common landlock_restrict_self sys_landlock_restrict_self diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl index 3abef2144dac..331663efd3e7 100644 --- a/arch/s390/kernel/syscalls/syscall.tbl +++ b/arch/s390/kernel/syscalls/syscall.tbl @@ -445,3 +445,6 @@ 440 common process_madvise sys_process_madvise sys_process_madvise 441 common epoll_pwait2 sys_epoll_pwait2 compat_sys_epoll_pwait2 442 common mount_setattr sys_mount_setattr sys_mount_setattr +444 common landlock_create_ruleset sys_landlock_create_ruleset sys_landlock_create_ruleset +445 common landlock_add_rule sys_landlock_add_rule sys_landlock_add_rule +446 common landlock_restrict_self sys_landlock_restrict_self sys_landlock_restrict_self diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl index d08eebad6b7f..6ada711f4b72 100644 --- a/arch/sh/kernel/syscalls/syscall.tbl +++ b/arch/sh/kernel/syscalls/syscall.tbl @@ -445,3 +445,6 @@ 440 common process_madvise sys_process_madvise 441 common epoll_pwait2 sys_epoll_pwait2 442 common mount_setattr sys_mount_setattr +444 common landlock_create_ruleset sys_landlock_create_ruleset +445 common landlock_add_rule sys_landlock_add_rule +446 common landlock_restrict_self sys_landlock_restrict_self diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl index 84403a99039c..1dbe3239a638 100644 --- a/arch/sparc/kernel/syscalls/syscall.tbl +++ b/arch/sparc/kernel/syscalls/syscall.tbl @@ -488,3 +488,6 @@ 440 common process_madvise sys_process_madvise 441 common epoll_pwait2 sys_epoll_pwait2 compat_sys_epoll_pwait2 442 common mount_setattr sys_mount_setattr +444 common landlock_create_ruleset sys_landlock_create_ruleset +445 common landlock_add_rule sys_landlock_add_rule +446 common landlock_restrict_self sys_landlock_restrict_self diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl index a1c9f496fca6..782c310de1da 100644 --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl @@ -447,3 +447,6 @@ 440 i386 process_madvise sys_process_madvise 441 i386 epoll_pwait2 sys_epoll_pwait2 compat_sys_epoll_pwait2 442 i386 mount_setattr sys_mount_setattr +444 i386 landlock_create_ruleset sys_landlock_create_ruleset +445 i386 landlock_add_rule sys_landlock_add_rule +446 i386 landlock_restrict_self sys_landlock_restrict_self diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index 7bf01cbe582f..8604ee4bfff9 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -364,6 +364,9 @@ 440 common process_madvise sys_process_madvise 441 common epoll_pwait2 sys_epoll_pwait2 442 common mount_setattr sys_mount_setattr +444 common landlock_create_ruleset sys_landlock_create_ruleset +445 common landlock_add_rule sys_landlock_add_rule +446 common landlock_restrict_self sys_landlock_restrict_self # # Due to a historical design error, certain syscalls are numbered differently diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl index 365a9b849224..2fad056a32e8 100644 --- a/arch/xtensa/kernel/syscalls/syscall.tbl +++ b/arch/xtensa/kernel/syscalls/syscall.tbl @@ -413,3 +413,6 @@ 440 common process_madvise sys_process_madvise 441 common epoll_pwait2 sys_epoll_pwait2 442 common mount_setattr sys_mount_setattr +444 common landlock_create_ruleset sys_landlock_create_ruleset +445 common landlock_add_rule sys_landlock_add_rule +446 common landlock_restrict_self sys_landlock_restrict_self diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h index ce58cff99b66..300608b05226 100644 --- a/include/uapi/asm-generic/unistd.h +++ b/include/uapi/asm-generic/unistd.h @@ -863,9 +863,15 @@ __SYSCALL(__NR_process_madvise, sys_process_madvise) __SC_COMP(__NR_epoll_pwait2, sys_epoll_pwait2, compat_sys_epoll_pwait2) #define __NR_mount_setattr 442 __SYSCALL(__NR_mount_setattr, sys_mount_setattr) +#define __NR_landlock_create_ruleset 444 +__SYSCALL(__NR_landlock_create_ruleset, sys_landlock_create_ruleset) +#define __NR_landlock_add_rule 445 +__SYSCALL(__NR_landlock_add_rule, sys_landlock_add_rule) +#define __NR_landlock_restrict_self 446 +__SYSCALL(__NR_landlock_restrict_self, sys_landlock_restrict_self) #undef __NR_syscalls -#define __NR_syscalls 443 +#define __NR_syscalls 447 /* * 32 bit systems traditionally used different -- cgit v1.2.3 From 265885daf3e5082eb9f6e2a23bdbf9ba4456a21b Mon Sep 17 00:00:00 2001 From: Mickaël Salaün Date: Thu, 22 Apr 2021 17:41:18 +0200 Subject: landlock: Add syscall implementations MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit These 3 system calls are designed to be used by unprivileged processes to sandbox themselves: * landlock_create_ruleset(2): Creates a ruleset and returns its file descriptor. * landlock_add_rule(2): Adds a rule (e.g. file hierarchy access) to a ruleset, identified by the dedicated file descriptor. * landlock_restrict_self(2): Enforces a ruleset on the calling thread and its future children (similar to seccomp). This syscall has the same usage restrictions as seccomp(2): the caller must have the no_new_privs attribute set or have CAP_SYS_ADMIN in the current user namespace. All these syscalls have a "flags" argument (not currently used) to enable extensibility. Here are the motivations for these new syscalls: * A sandboxed process may not have access to file systems, including /dev, /sys or /proc, but it should still be able to add more restrictions to itself. * Neither prctl(2) nor seccomp(2) (which was used in a previous version) fit well with the current definition of a Landlock security policy. All passed structs (attributes) are checked at build time to ensure that they don't contain holes and that they are aligned the same way for each architecture. See the user and kernel documentation for more details (provided by a following commit): * Documentation/userspace-api/landlock.rst * Documentation/security/landlock.rst Cc: Arnd Bergmann Cc: James Morris Cc: Jann Horn Cc: Kees Cook Signed-off-by: Mickaël Salaün Acked-by: Serge Hallyn Link: https://lore.kernel.org/r/20210422154123.13086-9-mic@digikod.net Signed-off-by: James Morris --- include/linux/syscalls.h | 7 + include/uapi/linux/landlock.h | 53 +++++ kernel/sys_ni.c | 5 + security/landlock/Makefile | 2 +- security/landlock/syscalls.c | 442 ++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 508 insertions(+), 1 deletion(-) create mode 100644 security/landlock/syscalls.c (limited to 'include/uapi') diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 2839dc9a7c01..fa3971012e1c 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -69,6 +69,8 @@ struct io_uring_params; struct clone_args; struct open_how; struct mount_attr; +struct landlock_ruleset_attr; +enum landlock_rule_type; #include #include @@ -1041,6 +1043,11 @@ asmlinkage long sys_pidfd_send_signal(int pidfd, int sig, siginfo_t __user *info, unsigned int flags); asmlinkage long sys_pidfd_getfd(int pidfd, int fd, unsigned int flags); +asmlinkage long sys_landlock_create_ruleset(const struct landlock_ruleset_attr __user *attr, + size_t size, __u32 flags); +asmlinkage long sys_landlock_add_rule(int ruleset_fd, enum landlock_rule_type rule_type, + const void __user *rule_attr, __u32 flags); +asmlinkage long sys_landlock_restrict_self(int ruleset_fd, __u32 flags); /* * Architecture-specific system calls diff --git a/include/uapi/linux/landlock.h b/include/uapi/linux/landlock.h index b1a81b5a8b86..ba946a1e40b2 100644 --- a/include/uapi/linux/landlock.h +++ b/include/uapi/linux/landlock.h @@ -9,6 +9,59 @@ #ifndef _UAPI_LINUX_LANDLOCK_H #define _UAPI_LINUX_LANDLOCK_H +#include + +/** + * struct landlock_ruleset_attr - Ruleset definition + * + * Argument of sys_landlock_create_ruleset(). This structure can grow in + * future versions. + */ +struct landlock_ruleset_attr { + /** + * @handled_access_fs: Bitmask of actions (cf. `Filesystem flags`_) + * that is handled by this ruleset and should then be forbidden if no + * rule explicitly allow them. This is needed for backward + * compatibility reasons. + */ + __u64 handled_access_fs; +}; + +/** + * enum landlock_rule_type - Landlock rule type + * + * Argument of sys_landlock_add_rule(). + */ +enum landlock_rule_type { + /** + * @LANDLOCK_RULE_PATH_BENEATH: Type of a &struct + * landlock_path_beneath_attr . + */ + LANDLOCK_RULE_PATH_BENEATH = 1, +}; + +/** + * struct landlock_path_beneath_attr - Path hierarchy definition + * + * Argument of sys_landlock_add_rule(). + */ +struct landlock_path_beneath_attr { + /** + * @allowed_access: Bitmask of allowed actions for this file hierarchy + * (cf. `Filesystem flags`_). + */ + __u64 allowed_access; + /** + * @parent_fd: File descriptor, open with ``O_PATH``, which identifies + * the parent directory of a file hierarchy, or just a file. + */ + __s32 parent_fd; + /* + * This struct is packed to avoid trailing reserved members. + * Cf. security/landlock/syscalls.c:build_check_abi() + */ +} __attribute__((packed)); + /** * DOC: fs_access * diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index 19aa806890d5..cce430cf2ff2 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c @@ -266,6 +266,11 @@ COND_SYSCALL(request_key); COND_SYSCALL(keyctl); COND_SYSCALL_COMPAT(keyctl); +/* security/landlock/syscalls.c */ +COND_SYSCALL(landlock_create_ruleset); +COND_SYSCALL(landlock_add_rule); +COND_SYSCALL(landlock_restrict_self); + /* arch/example/kernel/sys_example.c */ /* mm/fadvise.c */ diff --git a/security/landlock/Makefile b/security/landlock/Makefile index 92e3d80ab8ed..7bbd2f413b3e 100644 --- a/security/landlock/Makefile +++ b/security/landlock/Makefile @@ -1,4 +1,4 @@ obj-$(CONFIG_SECURITY_LANDLOCK) := landlock.o -landlock-y := setup.o object.o ruleset.o \ +landlock-y := setup.o syscalls.o object.o ruleset.o \ cred.o ptrace.o fs.o diff --git a/security/landlock/syscalls.c b/security/landlock/syscalls.c new file mode 100644 index 000000000000..93620ad7593b --- /dev/null +++ b/security/landlock/syscalls.c @@ -0,0 +1,442 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Landlock LSM - System call implementations and user space interfaces + * + * Copyright © 2016-2020 Mickaël Salaün + * Copyright © 2018-2020 ANSSI + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "cred.h" +#include "fs.h" +#include "limits.h" +#include "ruleset.h" +#include "setup.h" + +/** + * copy_min_struct_from_user - Safe future-proof argument copying + * + * Extend copy_struct_from_user() to check for consistent user buffer. + * + * @dst: Kernel space pointer or NULL. + * @ksize: Actual size of the data pointed to by @dst. + * @ksize_min: Minimal required size to be copied. + * @src: User space pointer or NULL. + * @usize: (Alleged) size of the data pointed to by @src. + */ +static __always_inline int copy_min_struct_from_user(void *const dst, + const size_t ksize, const size_t ksize_min, + const void __user *const src, const size_t usize) +{ + /* Checks buffer inconsistencies. */ + BUILD_BUG_ON(!dst); + if (!src) + return -EFAULT; + + /* Checks size ranges. */ + BUILD_BUG_ON(ksize <= 0); + BUILD_BUG_ON(ksize < ksize_min); + if (usize < ksize_min) + return -EINVAL; + if (usize > PAGE_SIZE) + return -E2BIG; + + /* Copies user buffer and fills with zeros. */ + return copy_struct_from_user(dst, ksize, src, usize); +} + +/* + * This function only contains arithmetic operations with constants, leading to + * BUILD_BUG_ON(). The related code is evaluated and checked at build time, + * but it is then ignored thanks to compiler optimizations. + */ +static void build_check_abi(void) +{ + struct landlock_ruleset_attr ruleset_attr; + struct landlock_path_beneath_attr path_beneath_attr; + size_t ruleset_size, path_beneath_size; + + /* + * For each user space ABI structures, first checks that there is no + * hole in them, then checks that all architectures have the same + * struct size. + */ + ruleset_size = sizeof(ruleset_attr.handled_access_fs); + BUILD_BUG_ON(sizeof(ruleset_attr) != ruleset_size); + BUILD_BUG_ON(sizeof(ruleset_attr) != 8); + + path_beneath_size = sizeof(path_beneath_attr.allowed_access); + path_beneath_size += sizeof(path_beneath_attr.parent_fd); + BUILD_BUG_ON(sizeof(path_beneath_attr) != path_beneath_size); + BUILD_BUG_ON(sizeof(path_beneath_attr) != 12); +} + +/* Ruleset handling */ + +static int fop_ruleset_release(struct inode *const inode, + struct file *const filp) +{ + struct landlock_ruleset *ruleset = filp->private_data; + + landlock_put_ruleset(ruleset); + return 0; +} + +static ssize_t fop_dummy_read(struct file *const filp, char __user *const buf, + const size_t size, loff_t *const ppos) +{ + /* Dummy handler to enable FMODE_CAN_READ. */ + return -EINVAL; +} + +static ssize_t fop_dummy_write(struct file *const filp, + const char __user *const buf, const size_t size, + loff_t *const ppos) +{ + /* Dummy handler to enable FMODE_CAN_WRITE. */ + return -EINVAL; +} + +/* + * A ruleset file descriptor enables to build a ruleset by adding (i.e. + * writing) rule after rule, without relying on the task's context. This + * reentrant design is also used in a read way to enforce the ruleset on the + * current task. + */ +static const struct file_operations ruleset_fops = { + .release = fop_ruleset_release, + .read = fop_dummy_read, + .write = fop_dummy_write, +}; + +/** + * sys_landlock_create_ruleset - Create a new ruleset + * + * @attr: Pointer to a &struct landlock_ruleset_attr identifying the scope of + * the new ruleset. + * @size: Size of the pointed &struct landlock_ruleset_attr (needed for + * backward and forward compatibility). + * @flags: Must be 0. + * + * This system call enables to create a new Landlock ruleset, and returns the + * related file descriptor on success. + * + * Possible returned errors are: + * + * - EOPNOTSUPP: Landlock is supported by the kernel but disabled at boot time; + * - EINVAL: @flags is not 0, or unknown access, or too small @size; + * - E2BIG or EFAULT: @attr or @size inconsistencies; + * - ENOMSG: empty &landlock_ruleset_attr.handled_access_fs. + */ +SYSCALL_DEFINE3(landlock_create_ruleset, + const struct landlock_ruleset_attr __user *const, attr, + const size_t, size, const __u32, flags) +{ + struct landlock_ruleset_attr ruleset_attr; + struct landlock_ruleset *ruleset; + int err, ruleset_fd; + + /* Build-time checks. */ + build_check_abi(); + + if (!landlock_initialized) + return -EOPNOTSUPP; + + /* No flag for now. */ + if (flags) + return -EINVAL; + + /* Copies raw user space buffer. */ + err = copy_min_struct_from_user(&ruleset_attr, sizeof(ruleset_attr), + offsetofend(typeof(ruleset_attr), handled_access_fs), + attr, size); + if (err) + return err; + + /* Checks content (and 32-bits cast). */ + if ((ruleset_attr.handled_access_fs | LANDLOCK_MASK_ACCESS_FS) != + LANDLOCK_MASK_ACCESS_FS) + return -EINVAL; + + /* Checks arguments and transforms to kernel struct. */ + ruleset = landlock_create_ruleset(ruleset_attr.handled_access_fs); + if (IS_ERR(ruleset)) + return PTR_ERR(ruleset); + + /* Creates anonymous FD referring to the ruleset. */ + ruleset_fd = anon_inode_getfd("landlock-ruleset", &ruleset_fops, + ruleset, O_RDWR | O_CLOEXEC); + if (ruleset_fd < 0) + landlock_put_ruleset(ruleset); + return ruleset_fd; +} + +/* + * Returns an owned ruleset from a FD. It is thus needed to call + * landlock_put_ruleset() on the return value. + */ +static struct landlock_ruleset *get_ruleset_from_fd(const int fd, + const fmode_t mode) +{ + struct fd ruleset_f; + struct landlock_ruleset *ruleset; + + ruleset_f = fdget(fd); + if (!ruleset_f.file) + return ERR_PTR(-EBADF); + + /* Checks FD type and access right. */ + if (ruleset_f.file->f_op != &ruleset_fops) { + ruleset = ERR_PTR(-EBADFD); + goto out_fdput; + } + if (!(ruleset_f.file->f_mode & mode)) { + ruleset = ERR_PTR(-EPERM); + goto out_fdput; + } + ruleset = ruleset_f.file->private_data; + if (WARN_ON_ONCE(ruleset->num_layers != 1)) { + ruleset = ERR_PTR(-EINVAL); + goto out_fdput; + } + landlock_get_ruleset(ruleset); + +out_fdput: + fdput(ruleset_f); + return ruleset; +} + +/* Path handling */ + +/* + * @path: Must call put_path(@path) after the call if it succeeded. + */ +static int get_path_from_fd(const s32 fd, struct path *const path) +{ + struct fd f; + int err = 0; + + BUILD_BUG_ON(!__same_type(fd, + ((struct landlock_path_beneath_attr *)NULL)->parent_fd)); + + /* Handles O_PATH. */ + f = fdget_raw(fd); + if (!f.file) + return -EBADF; + /* + * Forbids ruleset FDs, internal filesystems (e.g. nsfs), including + * pseudo filesystems that will never be mountable (e.g. sockfs, + * pipefs). + */ + if ((f.file->f_op == &ruleset_fops) || + (f.file->f_path.mnt->mnt_flags & MNT_INTERNAL) || + (f.file->f_path.dentry->d_sb->s_flags & SB_NOUSER) || + d_is_negative(f.file->f_path.dentry) || + IS_PRIVATE(d_backing_inode(f.file->f_path.dentry))) { + err = -EBADFD; + goto out_fdput; + } + *path = f.file->f_path; + path_get(path); + +out_fdput: + fdput(f); + return err; +} + +/** + * sys_landlock_add_rule - Add a new rule to a ruleset + * + * @ruleset_fd: File descriptor tied to the ruleset that should be extended + * with the new rule. + * @rule_type: Identify the structure type pointed to by @rule_attr (only + * LANDLOCK_RULE_PATH_BENEATH for now). + * @rule_attr: Pointer to a rule (only of type &struct + * landlock_path_beneath_attr for now). + * @flags: Must be 0. + * + * This system call enables to define a new rule and add it to an existing + * ruleset. + * + * Possible returned errors are: + * + * - EOPNOTSUPP: Landlock is supported by the kernel but disabled at boot time; + * - EINVAL: @flags is not 0, or inconsistent access in the rule (i.e. + * &landlock_path_beneath_attr.allowed_access is not a subset of the rule's + * accesses); + * - ENOMSG: Empty accesses (e.g. &landlock_path_beneath_attr.allowed_access); + * - EBADF: @ruleset_fd is not a file descriptor for the current thread, or a + * member of @rule_attr is not a file descriptor as expected; + * - EBADFD: @ruleset_fd is not a ruleset file descriptor, or a member of + * @rule_attr is not the expected file descriptor type (e.g. file open + * without O_PATH); + * - EPERM: @ruleset_fd has no write access to the underlying ruleset; + * - EFAULT: @rule_attr inconsistency. + */ +SYSCALL_DEFINE4(landlock_add_rule, + const int, ruleset_fd, const enum landlock_rule_type, rule_type, + const void __user *const, rule_attr, const __u32, flags) +{ + struct landlock_path_beneath_attr path_beneath_attr; + struct path path; + struct landlock_ruleset *ruleset; + int res, err; + + if (!landlock_initialized) + return -EOPNOTSUPP; + + /* No flag for now. */ + if (flags) + return -EINVAL; + + if (rule_type != LANDLOCK_RULE_PATH_BENEATH) + return -EINVAL; + + /* Copies raw user space buffer, only one type for now. */ + res = copy_from_user(&path_beneath_attr, rule_attr, + sizeof(path_beneath_attr)); + if (res) + return -EFAULT; + + /* Gets and checks the ruleset. */ + ruleset = get_ruleset_from_fd(ruleset_fd, FMODE_CAN_WRITE); + if (IS_ERR(ruleset)) + return PTR_ERR(ruleset); + + /* + * Informs about useless rule: empty allowed_access (i.e. deny rules) + * are ignored in path walks. + */ + if (!path_beneath_attr.allowed_access) { + err = -ENOMSG; + goto out_put_ruleset; + } + /* + * Checks that allowed_access matches the @ruleset constraints + * (ruleset->fs_access_masks[0] is automatically upgraded to 64-bits). + */ + if ((path_beneath_attr.allowed_access | ruleset->fs_access_masks[0]) != + ruleset->fs_access_masks[0]) { + err = -EINVAL; + goto out_put_ruleset; + } + + /* Gets and checks the new rule. */ + err = get_path_from_fd(path_beneath_attr.parent_fd, &path); + if (err) + goto out_put_ruleset; + + /* Imports the new rule. */ + err = landlock_append_fs_rule(ruleset, &path, + path_beneath_attr.allowed_access); + path_put(&path); + +out_put_ruleset: + landlock_put_ruleset(ruleset); + return err; +} + +/* Enforcement */ + +/** + * sys_landlock_restrict_self - Enforce a ruleset on the calling thread + * + * @ruleset_fd: File descriptor tied to the ruleset to merge with the target. + * @flags: Must be 0. + * + * This system call enables to enforce a Landlock ruleset on the current + * thread. Enforcing a ruleset requires that the task has CAP_SYS_ADMIN in its + * namespace or is running with no_new_privs. This avoids scenarios where + * unprivileged tasks can affect the behavior of privileged children. + * + * Possible returned errors are: + * + * - EOPNOTSUPP: Landlock is supported by the kernel but disabled at boot time; + * - EINVAL: @flags is not 0. + * - EBADF: @ruleset_fd is not a file descriptor for the current thread; + * - EBADFD: @ruleset_fd is not a ruleset file descriptor; + * - EPERM: @ruleset_fd has no read access to the underlying ruleset, or the + * current thread is not running with no_new_privs, or it doesn't have + * CAP_SYS_ADMIN in its namespace. + * - E2BIG: The maximum number of stacked rulesets is reached for the current + * thread. + */ +SYSCALL_DEFINE2(landlock_restrict_self, + const int, ruleset_fd, const __u32, flags) +{ + struct landlock_ruleset *new_dom, *ruleset; + struct cred *new_cred; + struct landlock_cred_security *new_llcred; + int err; + + if (!landlock_initialized) + return -EOPNOTSUPP; + + /* No flag for now. */ + if (flags) + return -EINVAL; + + /* + * Similar checks as for seccomp(2), except that an -EPERM may be + * returned. + */ + if (!task_no_new_privs(current) && + !ns_capable_noaudit(current_user_ns(), CAP_SYS_ADMIN)) + return -EPERM; + + /* Gets and checks the ruleset. */ + ruleset = get_ruleset_from_fd(ruleset_fd, FMODE_CAN_READ); + if (IS_ERR(ruleset)) + return PTR_ERR(ruleset); + + /* Prepares new credentials. */ + new_cred = prepare_creds(); + if (!new_cred) { + err = -ENOMEM; + goto out_put_ruleset; + } + new_llcred = landlock_cred(new_cred); + + /* + * There is no possible race condition while copying and manipulating + * the current credentials because they are dedicated per thread. + */ + new_dom = landlock_merge_ruleset(new_llcred->domain, ruleset); + if (IS_ERR(new_dom)) { + err = PTR_ERR(new_dom); + goto out_put_creds; + } + + /* Replaces the old (prepared) domain. */ + landlock_put_ruleset(new_llcred->domain); + new_llcred->domain = new_dom; + + landlock_put_ruleset(ruleset); + return commit_creds(new_cred); + +out_put_creds: + abort_creds(new_cred); + +out_put_ruleset: + landlock_put_ruleset(ruleset); + return err; +} -- cgit v1.2.3 From 3532b0b4352ce79400b0aa68414f1a0fc422b920 Mon Sep 17 00:00:00 2001 From: Mickaël Salaün Date: Thu, 22 Apr 2021 17:41:23 +0200 Subject: landlock: Enable user space to infer supported features MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add a new flag LANDLOCK_CREATE_RULESET_VERSION to landlock_create_ruleset(2). This enables to retreive a Landlock ABI version that is useful to efficiently follow a best-effort security approach. Indeed, it would be a missed opportunity to abort the whole sandbox building, because some features are unavailable, instead of protecting users as much as possible with the subset of features provided by the running kernel. This new flag enables user space to identify the minimum set of Landlock features supported by the running kernel without relying on a filesystem interface (e.g. /proc/version, which might be inaccessible) nor testing multiple syscall argument combinations (i.e. syscall bisection). New Landlock features will be documented and tied to a minimum version number (greater than 1). The current version will be incremented for each new kernel release supporting new Landlock features. User space libraries can leverage this information to seamlessly restrict processes as much as possible while being compatible with newer APIs. This is a much more lighter approach than the previous landlock_get_features(2): the complexity is pushed to user space libraries. This flag meets similar needs as securityfs versions: selinux/policyvers, apparmor/features/*/version* and tomoyo/version. Supporting this flag now will be convenient for backward compatibility. Cc: Arnd Bergmann Cc: James Morris Cc: Jann Horn Cc: Kees Cook Cc: Serge E. Hallyn Signed-off-by: Mickaël Salaün Link: https://lore.kernel.org/r/20210422154123.13086-14-mic@digikod.net Signed-off-by: James Morris --- include/uapi/linux/landlock.h | 8 +++++ security/landlock/syscalls.c | 17 +++++++--- tools/testing/selftests/landlock/base_test.c | 47 ++++++++++++++++++++++++++++ 3 files changed, 68 insertions(+), 4 deletions(-) (limited to 'include/uapi') diff --git a/include/uapi/linux/landlock.h b/include/uapi/linux/landlock.h index ba946a1e40b2..b3d952067f59 100644 --- a/include/uapi/linux/landlock.h +++ b/include/uapi/linux/landlock.h @@ -27,6 +27,14 @@ struct landlock_ruleset_attr { __u64 handled_access_fs; }; +/* + * sys_landlock_create_ruleset() flags: + * + * - %LANDLOCK_CREATE_RULESET_VERSION: Get the highest supported Landlock ABI + * version. + */ +#define LANDLOCK_CREATE_RULESET_VERSION (1U << 0) + /** * enum landlock_rule_type - Landlock rule type * diff --git a/security/landlock/syscalls.c b/security/landlock/syscalls.c index 93620ad7593b..32396962f04d 100644 --- a/security/landlock/syscalls.c +++ b/security/landlock/syscalls.c @@ -128,6 +128,8 @@ static const struct file_operations ruleset_fops = { .write = fop_dummy_write, }; +#define LANDLOCK_ABI_VERSION 1 + /** * sys_landlock_create_ruleset - Create a new ruleset * @@ -135,15 +137,19 @@ static const struct file_operations ruleset_fops = { * the new ruleset. * @size: Size of the pointed &struct landlock_ruleset_attr (needed for * backward and forward compatibility). - * @flags: Must be 0. + * @flags: Supported value: %LANDLOCK_CREATE_RULESET_VERSION. * * This system call enables to create a new Landlock ruleset, and returns the * related file descriptor on success. * + * If @flags is %LANDLOCK_CREATE_RULESET_VERSION and @attr is NULL and @size is + * 0, then the returned value is the highest supported Landlock ABI version + * (starting at 1). + * * Possible returned errors are: * * - EOPNOTSUPP: Landlock is supported by the kernel but disabled at boot time; - * - EINVAL: @flags is not 0, or unknown access, or too small @size; + * - EINVAL: unknown @flags, or unknown access, or too small @size; * - E2BIG or EFAULT: @attr or @size inconsistencies; * - ENOMSG: empty &landlock_ruleset_attr.handled_access_fs. */ @@ -161,9 +167,12 @@ SYSCALL_DEFINE3(landlock_create_ruleset, if (!landlock_initialized) return -EOPNOTSUPP; - /* No flag for now. */ - if (flags) + if (flags) { + if ((flags == LANDLOCK_CREATE_RULESET_VERSION) + && !attr && !size) + return LANDLOCK_ABI_VERSION; return -EINVAL; + } /* Copies raw user space buffer. */ err = copy_min_struct_from_user(&ruleset_attr, sizeof(ruleset_attr), diff --git a/tools/testing/selftests/landlock/base_test.c b/tools/testing/selftests/landlock/base_test.c index 262c3c8d953a..ca40abe9daa8 100644 --- a/tools/testing/selftests/landlock/base_test.c +++ b/tools/testing/selftests/landlock/base_test.c @@ -63,6 +63,53 @@ TEST(inconsistent_attr) { free(buf); } +TEST(abi_version) { + const struct landlock_ruleset_attr ruleset_attr = { + .handled_access_fs = LANDLOCK_ACCESS_FS_READ_FILE, + }; + ASSERT_EQ(1, landlock_create_ruleset(NULL, 0, + LANDLOCK_CREATE_RULESET_VERSION)); + + ASSERT_EQ(-1, landlock_create_ruleset(&ruleset_attr, 0, + LANDLOCK_CREATE_RULESET_VERSION)); + ASSERT_EQ(EINVAL, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(NULL, sizeof(ruleset_attr), + LANDLOCK_CREATE_RULESET_VERSION)); + ASSERT_EQ(EINVAL, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(&ruleset_attr, + sizeof(ruleset_attr), + LANDLOCK_CREATE_RULESET_VERSION)); + ASSERT_EQ(EINVAL, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(NULL, 0, + LANDLOCK_CREATE_RULESET_VERSION | 1 << 31)); + ASSERT_EQ(EINVAL, errno); +} + +TEST(inval_create_ruleset_flags) { + const int last_flag = LANDLOCK_CREATE_RULESET_VERSION; + const int invalid_flag = last_flag << 1; + const struct landlock_ruleset_attr ruleset_attr = { + .handled_access_fs = LANDLOCK_ACCESS_FS_READ_FILE, + }; + + ASSERT_EQ(-1, landlock_create_ruleset(NULL, 0, invalid_flag)); + ASSERT_EQ(EINVAL, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(&ruleset_attr, 0, invalid_flag)); + ASSERT_EQ(EINVAL, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(NULL, sizeof(ruleset_attr), + invalid_flag)); + ASSERT_EQ(EINVAL, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(&ruleset_attr, + sizeof(ruleset_attr), invalid_flag)); + ASSERT_EQ(EINVAL, errno); +} + TEST(empty_path_beneath_attr) { const struct landlock_ruleset_attr ruleset_attr = { .handled_access_fs = LANDLOCK_ACCESS_FS_EXECUTE, -- cgit v1.2.3