[SPARC64]: Add SECCOMP support.

Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc64/Kconfig

@@ -43,6 +43,23 @@ config SPARC64_PAGE_SIZE_4MB
 
 endchoice
 
+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. Only embedded should say N here.
+
 source kernel/Kconfig.hz
 
 source "init/Kconfig"

arch/sparc64/kernel/entry.S

@@ -1552,7 +1552,7 @@ sys_ptrace:	add		%sp, PTREGS_OFF, %o0
 		nop
 		.align		32
 1:		ldx		[%curptr + TI_FLAGS], %l5
-		andcc		%l5, _TIF_SYSCALL_TRACE, %g0
+		andcc		%l5, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP), %g0
 		be,pt		%icc, rtrap
 		 clr		%l6
 		call		syscall_trace
@@ -1676,7 +1676,7 @@ linux_sparc_syscall32:
 
 	srl		%i5, 0, %o5				! IEU1
 	srl		%i2, 0, %o2				! IEU0	Group
-	andcc		%l0, _TIF_SYSCALL_TRACE, %g0		! IEU0	Group
+	andcc		%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP), %g0 ! IEU0	Group
 	bne,pn		%icc, linux_syscall_trace32		! CTI
 	 mov		%i0, %l5				! IEU1
 	call		%l7					! CTI	Group brk forced
@@ -1699,7 +1699,7 @@ linux_sparc_syscall:
 
 	mov		%i3, %o3				! IEU1
 	mov		%i4, %o4				! IEU0	Group
-	andcc		%l0, _TIF_SYSCALL_TRACE, %g0		! IEU1	Group+1 bubble
+	andcc		%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP), %g0 ! IEU1	Group+1 bubble
 	bne,pn		%icc, linux_syscall_trace		! CTI	Group
 	 mov		%i0, %l5				! IEU0
 2:	call		%l7					! CTI	Group brk forced
@@ -1727,7 +1727,7 @@ ret_sys_call:
 1:
 	cmp		%o0, -ERESTART_RESTARTBLOCK
 	bgeu,pn		%xcc, 1f
-	 andcc		%l0, _TIF_SYSCALL_TRACE, %l6	
+	 andcc		%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP), %l6
 80:
 	/* System call success, clear Carry condition code. */
 	andn		%g3, %g2, %g3
@@ -1742,7 +1742,7 @@ ret_sys_call:
 	/* System call failure, set Carry condition code.
 	 * Also, get abs(errno) to return to the process.
 	 */
-	andcc		%l0, _TIF_SYSCALL_TRACE, %l6	
+	andcc		%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP), %l6	
 	sub		%g0, %o0, %o0
 	or		%g3, %g2, %g3
 	stx		%o0, [%sp + PTREGS_OFF + PT_V9_I0]

arch/sparc64/kernel/power.c

@@ -4,6 +4,8 @@
  * Copyright (C) 1999 David S. Miller (davem@redhat.com)
  */
 
+#define __KERNEL_SYSCALLS__
+
 #include <linux/config.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -17,7 +19,6 @@
 #include <asm/ebus.h>
 #include <asm/auxio.h>
 
-#define __KERNEL_SYSCALLS__
 #include <linux/unistd.h>
 
 /*

arch/sparc64/kernel/ptrace.c

@@ -630,9 +630,9 @@ out:
 
 asmlinkage void syscall_trace(void)
 {
-#ifdef DEBUG_PTRACE
-	printk("%s [%d]: syscall_trace\n", current->comm, current->pid);
-#endif
+	/* do the secure computing check first */
+	secure_computing(current_thread_info()->kregs->u_regs[UREG_G1]);
+
 	if (!test_thread_flag(TIF_SYSCALL_TRACE))
 		return;
 	if (!(current->ptrace & PT_PTRACED))
@@ -645,12 +645,8 @@ asmlinkage void syscall_trace(void)
 	 * for normal use.  strace only continues with a signal if the
 	 * stopping signal is not SIGTRAP.  -brl
 	 */
-#ifdef DEBUG_PTRACE
-	printk("%s [%d]: syscall_trace exit= %x\n", current->comm,
-		current->pid, current->exit_code);
-#endif
 	if (current->exit_code) {
-		send_sig (current->exit_code, current, 1);
+		send_sig(current->exit_code, current, 1);
 		current->exit_code = 0;
 	}
 }

include/asm-sparc64/thread_info.h

@@ -220,7 +220,7 @@ register struct thread_info *current_thread_info_reg asm("g6");
 #define TIF_NEWSIGNALS		6	/* wants new-style signals */
 #define TIF_32BIT		7	/* 32-bit binary */
 #define TIF_NEWCHILD		8	/* just-spawned child process */
-/* TIF_* value 9 is available */
+#define TIF_SECCOMP		9	/* secure computing */
 #define TIF_POLLING_NRFLAG	10
 #define TIF_SYSCALL_SUCCESS	11
 /* NOTE: Thread flags >= 12 should be ones we have no interest
@@ -239,6 +239,7 @@ register struct thread_info *current_thread_info_reg asm("g6");
 #define _TIF_NEWSIGNALS		(1<<TIF_NEWSIGNALS)
 #define _TIF_32BIT		(1<<TIF_32BIT)
 #define _TIF_NEWCHILD		(1<<TIF_NEWCHILD)
+#define _TIF_SECCOMP		(1<<TIF_SECCOMP)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
 #define _TIF_ABI_PENDING	(1<<TIF_ABI_PENDING)
 #define _TIF_SYSCALL_SUCCESS	(1<<TIF_SYSCALL_SUCCESS)