diff options
| -rw-r--r-- | arch/s390/Kconfig | 18 | ||||
| -rw-r--r-- | arch/s390/include/asm/seccomp.h | 16 | ||||
| -rw-r--r-- | arch/s390/include/asm/thread_info.h | 10 | ||||
| -rw-r--r-- | arch/s390/kernel/entry.S | 5 | ||||
| -rw-r--r-- | arch/s390/kernel/entry64.S | 5 | ||||
| -rw-r--r-- | arch/s390/kernel/ptrace.c | 6 |
6 files changed, 51 insertions, 9 deletions
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 2eca5fe0e75b..1094787e97e5 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -567,6 +567,24 @@ bool "s390 guest support for KVM (EXPERIMENTAL)" the KVM hypervisor. This will add detection for KVM as well as a virtio transport. If KVM is detected, the virtio console will be the default console. + +config SECCOMP + bool "Enable seccomp to safely compute untrusted bytecode" + depends on PROC_FS + default y + 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 /proc/<pid>/seccomp, it cannot be disabled + and the task is only allowed to execute a few safe syscalls + defined by each seccomp mode. + + If unsure, say Y. + endmenu source "net/Kconfig" diff --git a/arch/s390/include/asm/seccomp.h b/arch/s390/include/asm/seccomp.h new file mode 100644 index 000000000000..781a9cf9b002 --- /dev/null +++ b/arch/s390/include/asm/seccomp.h @@ -0,0 +1,16 @@ +#ifndef _ASM_S390_SECCOMP_H +#define _ASM_S390_SECCOMP_H + +#include <linux/unistd.h> + +#define __NR_seccomp_read __NR_read +#define __NR_seccomp_write __NR_write +#define __NR_seccomp_exit __NR_exit +#define __NR_seccomp_sigreturn __NR_sigreturn + +#define __NR_seccomp_read_32 __NR_read +#define __NR_seccomp_write_32 __NR_write +#define __NR_seccomp_exit_32 __NR_exit +#define __NR_seccomp_sigreturn_32 __NR_sigreturn + +#endif /* _ASM_S390_SECCOMP_H */ diff --git a/arch/s390/include/asm/thread_info.h b/arch/s390/include/asm/thread_info.h index 461f2abd2e6f..2f86653dda69 100644 --- a/arch/s390/include/asm/thread_info.h +++ b/arch/s390/include/asm/thread_info.h @@ -83,14 +83,15 @@ static inline struct thread_info *current_thread_info(void) /* * thread information flags bit numbers */ -#define TIF_SYSCALL_TRACE 0 /* syscall trace active */ #define TIF_NOTIFY_RESUME 1 /* callback before returning to user */ #define TIF_SIGPENDING 2 /* signal pending */ #define TIF_NEED_RESCHED 3 /* rescheduling necessary */ #define TIF_RESTART_SVC 4 /* restart svc with new svc number */ -#define TIF_SYSCALL_AUDIT 5 /* syscall auditing active */ #define TIF_SINGLE_STEP 6 /* deliver sigtrap on return to user */ #define TIF_MCCK_PENDING 7 /* machine check handling is pending */ +#define TIF_SYSCALL_TRACE 8 /* syscall trace active */ +#define TIF_SYSCALL_AUDIT 9 /* syscall auditing active */ +#define TIF_SECCOMP 10 /* secure computing */ #define TIF_USEDFPU 16 /* FPU was used by this task this quantum (SMP) */ #define TIF_POLLING_NRFLAG 17 /* true if poll_idle() is polling TIF_NEED_RESCHED */ @@ -99,15 +100,16 @@ static inline struct thread_info *current_thread_info(void) #define TIF_RESTORE_SIGMASK 20 /* restore signal mask in do_signal() */ #define TIF_FREEZE 21 /* thread is freezing for suspend */ -#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE) #define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME) #define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK) #define _TIF_SIGPENDING (1<<TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED) #define _TIF_RESTART_SVC (1<<TIF_RESTART_SVC) -#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT) #define _TIF_SINGLE_STEP (1<<TIF_SINGLE_STEP) #define _TIF_MCCK_PENDING (1<<TIF_MCCK_PENDING) +#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE) +#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT) +#define _TIF_SECCOMP (1<<TIF_SECCOMP) #define _TIF_USEDFPU (1<<TIF_USEDFPU) #define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG) #define _TIF_31BIT (1<<TIF_31BIT) diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S index f3e275934213..db25cdc21e12 100644 --- a/arch/s390/kernel/entry.S +++ b/arch/s390/kernel/entry.S @@ -53,6 +53,7 @@ _TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \ _TIF_MCCK_PENDING | _TIF_RESTART_SVC | _TIF_SINGLE_STEP ) _TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \ _TIF_MCCK_PENDING) +_TIF_SYSCALL = (_TIF_SYSCALL_TRACE>>8 | _TIF_SYSCALL_AUDIT>>8 | _TIF_SECCOMP>>8) STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER STACK_SIZE = 1 << STACK_SHIFT @@ -265,7 +266,7 @@ sysc_do_restart: sth %r7,SP_SVCNR(%r15) sll %r7,2 # svc number *4 l %r8,BASED(.Lsysc_table) - tm __TI_flags+3(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT) + tm __TI_flags+2(%r9),_TIF_SYSCALL l %r8,0(%r7,%r8) # get system call addr. bnz BASED(sysc_tracesys) basr %r14,%r8 # call sys_xxxx @@ -405,7 +406,7 @@ sysc_tracego: basr %r14,%r8 # call sys_xxx st %r2,SP_R2(%r15) # store return value sysc_tracenogo: - tm __TI_flags+3(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT) + tm __TI_flags+2(%r9),_TIF_SYSCALL bz BASED(sysc_return) l %r1,BASED(.Ltrace_exit) la %r2,SP_PTREGS(%r15) # load pt_regs diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S index 84a105838e03..3cec9b504f5f 100644 --- a/arch/s390/kernel/entry64.S +++ b/arch/s390/kernel/entry64.S @@ -56,6 +56,7 @@ _TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \ _TIF_MCCK_PENDING | _TIF_RESTART_SVC | _TIF_SINGLE_STEP ) _TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \ _TIF_MCCK_PENDING) +_TIF_SYSCALL = (_TIF_SYSCALL_TRACE>>8 | _TIF_SYSCALL_AUDIT>>8 | _TIF_SECCOMP>>8) #define BASED(name) name-system_call(%r13) @@ -260,7 +261,7 @@ sysc_do_restart: larl %r10,sys_call_table_emu # use 31 bit emulation system calls sysc_noemu: #endif - tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT) + tm __TI_flags+6(%r9),_TIF_SYSCALL lgf %r8,0(%r7,%r10) # load address of system call routine jnz sysc_tracesys basr %r14,%r8 # call sys_xxxx @@ -391,7 +392,7 @@ sysc_tracego: basr %r14,%r8 # call sys_xxx stg %r2,SP_R2(%r15) # store return value sysc_tracenogo: - tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT) + tm __TI_flags+6(%r9),_TIF_SYSCALL jz sysc_return la %r2,SP_PTREGS(%r15) # load pt_regs larl %r14,sysc_return # return point is sysc_return diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c index 99eef179e903..b6fc1ae2ffcb 100644 --- a/arch/s390/kernel/ptrace.c +++ b/arch/s390/kernel/ptrace.c @@ -36,7 +36,8 @@ #include <linux/elf.h> #include <linux/regset.h> #include <linux/tracehook.h> -#include <linux/compat.h> +#include <linux/seccomp.h> +#include <asm/compat.h> #include <asm/segment.h> #include <asm/page.h> #include <asm/pgtable.h> @@ -640,6 +641,9 @@ asmlinkage long do_syscall_trace_enter(struct pt_regs *regs) { long ret; + /* Do the secure computing check first. */ + secure_computing(regs->gprs[2]); + /* * The sysc_tracesys code in entry.S stored the system * call number to gprs[2]. |