This patch series enable secure computing (system call filtering) on arm64, and contain related enhancements and bug fixes.
This code was tested on ARMv8 fast model with 64-bit/32-bit userspace using * libseccomp v2.1.1 with modifications for arm64, especially its "live" tests: No.20, 21 and 24. * modified version of Kees' seccomp test for 'changing/skipping a syscall' and seccomp() system call * in-house tests for 'changing/skipping a system call' in tracing with ptrace(PTRACE_SYSCALL) (that is, without seccomp)' with and without audit tracing.
Changes v5 -> v6: * rebased to v3.17-rc * changed the interface of changing/skipping a system call from re-writing x8 register [v5 1/3] to using dedicated PTRACE_SET_SYSCALL command [1/6, 2/6] Patch [1/6] contains a checkpatch error around a switch statement, but it won't be fixed as in compat_arch_ptrace(). * added a new system call, seccomp(), for compat task [4/6] * added SIGSYS siginfo for compat task [5/6] * changed to always execute audit exit tracing to avoid OOPs [2/6, 6/6]
Changes v4 -> v5: * rebased to v3.16-rc * add patch [1/3] to allow ptrace to change a system call (please note that this patch should be applied even without seccomp.)
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 (6): arm64: ptrace: add PTRACE_SET_SYSCALL arm64: ptrace: allow tracer to skip a system call asm-generic: add generic seccomp.h for secure computing mode 1 arm64: add seccomp syscall for compat task arm64: add SIGSYS siginfo for compat task arm64: add seccomp support
arch/arm64/Kconfig | 14 ++++++++++++ arch/arm64/include/asm/compat.h | 7 ++++++ arch/arm64/include/asm/ptrace.h | 9 ++++++++ arch/arm64/include/asm/seccomp.h | 25 ++++++++++++++++++++++ arch/arm64/include/asm/unistd.h | 5 ++++- arch/arm64/include/asm/unistd32.h | 3 +++ arch/arm64/include/uapi/asm/ptrace.h | 1 + arch/arm64/kernel/entry.S | 6 ++++++ arch/arm64/kernel/ptrace.c | 39 +++++++++++++++++++++++++++++++++- arch/arm64/kernel/signal32.c | 8 +++++++ include/asm-generic/seccomp.h | 28 ++++++++++++++++++++++++ 11 files changed, 143 insertions(+), 2 deletions(-) create mode 100644 arch/arm64/include/asm/seccomp.h create mode 100644 include/asm-generic/seccomp.h