diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index f5412d628ff6..7c79c6494379 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -38,6 +38,7 @@ config ARM64 select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_JUMP_LABEL select HAVE_ARCH_KGDB + select HAVE_ARCH_SECCOMP_FILTER select HAVE_ARCH_TRACEHOOK select HAVE_BPF_JIT select HAVE_C_RECORDMCOUNT @@ -455,6 +456,19 @@ config ARCH_HAS_CACHE_LINE_SIZE source "mm/Kconfig" +config SECCOMP + bool "Enable seccomp to safely compute untrusted bytecode" + ---help--- + This kernel feature is useful for number crunching applications + that may need to compute untrusted bytecode during their + execution. By using pipes or other transports made available to + the process as file descriptors supporting the read/write + syscalls, it's possible to isolate those applications in + their own address space using seccomp. Once seccomp is + enabled via prctl(PR_SET_SECCOMP), it cannot be disabled + and the task is only allowed to execute a few safe syscalls + defined by each seccomp mode. + config XEN_DOM0 def_bool y depends on XEN diff --git a/arch/arm64/include/asm/seccomp.h b/arch/arm64/include/asm/seccomp.h new file mode 100644 index 000000000000..c76fac979629 --- /dev/null +++ b/arch/arm64/include/asm/seccomp.h @@ -0,0 +1,25 @@ +/* + * arch/arm64/include/asm/seccomp.h + * + * Copyright (C) 2014 Linaro Limited + * Author: AKASHI Takahiro + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#ifndef _ASM_SECCOMP_H +#define _ASM_SECCOMP_H + +#include + +#ifdef CONFIG_COMPAT +#define __NR_seccomp_read_32 __NR_compat_read +#define __NR_seccomp_write_32 __NR_compat_write +#define __NR_seccomp_exit_32 __NR_compat_exit +#define __NR_seccomp_sigreturn_32 __NR_compat_rt_sigreturn +#endif /* CONFIG_COMPAT */ + +#include + +#endif /* _ASM_SECCOMP_H */ diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h index 6d2bf419431d..49c9aefd24a5 100644 --- a/arch/arm64/include/asm/unistd.h +++ b/arch/arm64/include/asm/unistd.h @@ -31,6 +31,9 @@ * Compat syscall numbers used by the AArch64 kernel. */ #define __NR_compat_restart_syscall 0 +#define __NR_compat_exit 1 +#define __NR_compat_read 3 +#define __NR_compat_write 4 #define __NR_compat_sigreturn 119 #define __NR_compat_rt_sigreturn 173 diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index f576781d8d3b..d882b833dbdb 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include #include @@ -1149,6 +1150,10 @@ static void tracehook_report_syscall(struct pt_regs *regs, asmlinkage int syscall_trace_enter(struct pt_regs *regs) { + /* Do the secure computing check first; failures should be fast. */ + if (secure_computing() == -1) + return -1; + if (test_thread_flag(TIF_SYSCALL_TRACE)) tracehook_report_syscall(regs, PTRACE_SYSCALL_ENTER);