(I don't think that discussions below about ptrace() have impact on this patchset. http://lists.infradead.org/pipermail/linux-arm-kernel/2014-July/268923.html )
(Please apply this patch after my audit patch in order to avoid some conflict on arm64/Kconfig.)
This patch enables secure computing (system call filtering) on arm64. System calls can be allowed or denied by loaded bpf-style rules. Architecture specific part is to run secure_computing() on syscall entry and check the result. See [2/2]
This code is tested on ARMv8 fast model using libseccomp v2.1.1 with modifications for arm64 and verified by its "live" tests, 20, 21 and 24.
Changes v3 -> v4: * removed the following patch and moved it to "arm64: prerequisites for audit and ftrace" patchset since it is required for audit and ftrace in case of !COMPAT, too. "arm64: is_compat_task is defined both in asm/compat.h and linux/compat.h"
Changes v2 -> v3: * removed unnecessary 'type cast' operations [2/3] * check for a return value (-1) of secure_computing() explicitly [2/3] * aligned with the patch, "arm64: split syscall_trace() into separate functions for enter/exit" [2/3] * changed default of CONFIG_SECCOMP to n [2/3]
Changes v1 -> v2: * added generic seccomp.h for arm64 to utilize it [1,2/3] * changed syscall_trace() to return more meaningful value (-EPERM) on seccomp failure case [2/3] * aligned with the change in "arm64: make a single hook to syscall_trace() for all syscall features" v2 [2/3] * removed is_compat_task() definition from compat.h [3/3]
AKASHI Takahiro (2): asm-generic: Add generic seccomp.h for secure computing mode 1 arm64: Add seccomp support
arch/arm64/Kconfig | 14 ++++++++++++++ arch/arm64/include/asm/seccomp.h | 25 +++++++++++++++++++++++++ arch/arm64/include/asm/unistd.h | 3 +++ arch/arm64/kernel/entry.S | 4 ++++ arch/arm64/kernel/ptrace.c | 6 ++++++ include/asm-generic/seccomp.h | 28 ++++++++++++++++++++++++++++ 6 files changed, 80 insertions(+) create mode 100644 arch/arm64/include/asm/seccomp.h create mode 100644 include/asm-generic/seccomp.h