Added a bunch of C files under arch/um/kernel/skas and

arch/um/kernel/tt.

arch/um/kernel/skas/include/proc_mm.h

+/* 
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#ifndef __SKAS_PROC_MM_H
+#define __SKAS_PROC_MM_H
+
+#define MM_MMAP 54
+#define MM_MUNMAP 55
+#define MM_MPROTECT 56
+#define MM_COPY_SEGMENTS 57
+
+struct mm_mmap {
+	unsigned long addr;
+	unsigned long len;
+	unsigned long prot;
+	unsigned long flags;
+	unsigned long fd;
+	unsigned long offset;
+};
+
+struct mm_munmap {
+	unsigned long addr;
+	unsigned long len;	
+};
+
+struct mm_mprotect {
+	unsigned long addr;
+	unsigned long len;
+        unsigned int prot;
+};
+
+struct proc_mm_op {
+	int op;
+	union {
+		struct mm_mmap mmap;
+		struct mm_munmap munmap;
+	        struct mm_mprotect mprotect;
+		int copy_segments;
+	} u;
+};
+
+#endif
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */

arch/um/kernel/tt/syscall_user.c

+/* 
+ * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <unistd.h>
+#include <signal.h>
+#include <errno.h>
+#include <sys/ptrace.h>
+#include <asm/unistd.h>
+#include "sysdep/ptrace.h"
+#include "sigcontext.h"
+#include "ptrace_user.h"
+#include "task.h"
+#include "user_util.h"
+#include "kern_util.h"
+#include "syscall_user.h"
+#include "tt.h"
+
+/* XXX Bogus */
+#define ERESTARTSYS	512
+#define ERESTARTNOINTR	513
+#define ERESTARTNOHAND	514
+
+void syscall_handler_tt(int sig, struct uml_pt_regs *regs)
+{
+	void *sc;
+	long result;
+	int index, syscall;
+
+	syscall = regs->syscall;
+	sc = regs->mode.tt;
+	sc_to_regs(regs, sc, syscall);
+	SC_START_SYSCALL(sc);
+
+	index = record_syscall_start(syscall);
+	syscall_trace();
+	result = execute_syscall(regs);
+
+	/* regs->sc may have changed while the system call ran (there may
+	 * have been an interrupt or segfault), so it needs to be refreshed.
+	 */
+	regs->mode.tt = sc;
+
+	SC_SET_SYSCALL_RETURN(sc, result);
+	if((result == -ERESTARTNOHAND) || (result == -ERESTARTSYS) || 
+	   (result == -ERESTARTNOINTR))
+		do_signal(result);
+
+	syscall_trace();
+	record_syscall_end(index, result);
+}
+
+int do_syscall(void *task, int pid)
+{
+	unsigned long proc_regs[FRAME_SIZE];
+	struct uml_pt_regs *regs;
+	int syscall;
+
+	if(ptrace_getregs(pid, proc_regs) < 0)
+		tracer_panic("Couldn't read registers");
+	syscall = PT_SYSCALL_NR(proc_regs);
+
+	regs = TASK_REGS(task);
+	UPT_SYSCALL_NR(regs) = syscall;
+
+	if(syscall < 1) return(0);
+
+	if((syscall != __NR_sigreturn) &&
+	   ((unsigned long *) PT_IP(proc_regs) >= &_stext) && 
+	   ((unsigned long *) PT_IP(proc_regs) <= &_etext))
+		tracer_panic("I'm tracing myself and I can't get out");
+
+	if(ptrace(PTRACE_POKEUSER, pid, PT_SYSCALL_NR_OFFSET, 
+		  __NR_getpid) < 0)
+		tracer_panic("do_syscall : Nullifying syscall failed, "
+			     "errno = %d", errno);
+	return(1);
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */

arch/um/kernel/tt/tracer.c

+/* 
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <unistd.h>
+#include <signal.h>
+#include <errno.h>
+#include <sched.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/ptrace.h>
+#include <sys/time.h>
+#include <sys/wait.h>
+#include "user.h"
+#include "sysdep/ptrace.h"
+#include "sigcontext.h"
+#include "sysdep/sigcontext.h"
+#include "os.h"
+#include "signal_user.h"
+#include "user_util.h"
+#include "mem_user.h"
+#include "process.h"
+#include "kern_util.h"
+#include "frame.h"
+#include "chan_user.h"
+#include "ptrace_user.h"
+#include "mode.h"
+#include "tt.h"
+
+static int tracer_winch[2];
+
+int is_tracer_winch(int pid, int fd, void *data)
+{
+	if(pid != tracing_pid)
+		return(0);
+
+	register_winch_irq(tracer_winch[0], fd, -1, data);
+	return(0);
+}
+
+static void tracer_winch_handler(int sig)
+{
+	char c = 1;
+
+	if(write(tracer_winch[1], &c, sizeof(c)) != sizeof(c))
+		printk("tracer_winch_handler - write failed, errno = %d\n",
+		       errno);
+}
+
+/* Called only by the tracing thread during initialization */
+
+static void setup_tracer_winch(void)
+{
+	int err;
+
+	err = os_pipe(tracer_winch, 1, 1);
+	if(err){
+		printk("setup_tracer_winch : os_pipe failed, errno = %d\n", 
+		       -err);
+		return;
+	}
+	signal(SIGWINCH, tracer_winch_handler);
+}
+
+void attach_process(int pid)
+{
+	if((ptrace(PTRACE_ATTACH, pid, 0, 0) < 0) ||
+	   (ptrace(PTRACE_CONT, pid, 0, 0) < 0))
+		tracer_panic("OP_FORK failed to attach pid");
+	wait_for_stop(pid, SIGSTOP, PTRACE_CONT, NULL);
+	if(ptrace(PTRACE_CONT, pid, 0, 0) < 0)
+		tracer_panic("OP_FORK failed to continue process");
+}
+
+void tracer_panic(char *format, ...)
+{
+	va_list ap;
+
+	va_start(ap, format);
+	vprintf(format, ap);
+	printf("\n");
+	while(1) pause();
+}
+
+static void tracer_segv(int sig, struct sigcontext sc)
+{
+	printf("Tracing thread segfault at address 0x%lx, ip 0x%lx\n",
+	       SC_FAULT_ADDR(&sc), SC_IP(&sc));
+	while(1)
+		pause();
+}
+
+/* Changed early in boot, and then only read */
+int debug = 0;
+int debug_stop = 1;
+int debug_parent = 0;
+int honeypot = 0;
+
+static int signal_tramp(void *arg)
+{
+	int (*proc)(void *);
+
+	if(honeypot && munmap((void *) (host_task_size - 0x10000000),
+			      0x10000000)) 
+		panic("Unmapping stack failed");
+	if(ptrace(PTRACE_TRACEME, 0, 0, 0) < 0)
+		panic("ptrace PTRACE_TRACEME failed");
+	os_stop_process(os_getpid());
+	change_sig(SIGWINCH, 0);
+	signal(SIGUSR1, SIG_IGN);
+	change_sig(SIGCHLD, 0);
+	signal(SIGSEGV, (__sighandler_t) sig_handler);
+	set_cmdline("(idle thread)");
+	set_init_pid(os_getpid());
+	proc = arg;
+	return((*proc)(NULL));
+}
+
+static void last_ditch_exit(int sig)
+{
+	kmalloc_ok = 0;
+	signal(SIGINT, SIG_DFL);
+	signal(SIGTERM, SIG_DFL);
+	signal(SIGHUP, SIG_DFL);
+	uml_cleanup();
+	exit(1);
+}
+
+static void sleeping_process_signal(int pid, int sig)
+{
+	switch(sig){
+	/* These two result from UML being ^Z-ed and bg-ed.  PTRACE_CONT is
+	 * right because the process must be in the kernel already.
+	 */
+	case SIGCONT:
+	case SIGTSTP:
+		if(ptrace(PTRACE_CONT, pid, 0, sig) < 0)
+			tracer_panic("sleeping_process_signal : Failed to "
+				     "continue pid %d, errno = %d\n", pid,
+				     sig);
+		break;
+
+	/* This happens when the debugger (e.g. strace) is doing system call 
+	 * tracing on the kernel.  During a context switch, the current task
+	 * will be set to the incoming process and the outgoing process will
+	 * hop into write and then read.  Since it's not the current process
+	 * any more, the trace of those will land here.  So, we need to just 
+	 * PTRACE_SYSCALL it.
+	 */
+	case SIGTRAP:
+		if(ptrace(PTRACE_SYSCALL, pid, 0, 0) < 0)
+			tracer_panic("sleeping_process_signal : Failed to "
+				     "PTRACE_SYSCALL pid %d, errno = %d\n",
+				     pid, sig);
+		break;
+	case SIGSTOP:
+		break;
+	default:
+		tracer_panic("sleeping process %d got unexpected "
+			     "signal : %d\n", pid, sig);
+		break;
+	}
+}
+
+/* Accessed only by the tracing thread */
+int debugger_pid = -1;
+int debugger_parent = -1;
+int debugger_fd = -1;
+int gdb_pid = -1;
+
+struct {
+	int pid;
+	int signal;
+	unsigned long addr;
+	struct timeval time;
+} signal_record[1024][32];
+
+int signal_index[32];
+int nsignals = 0;
+int debug_trace = 0;
+extern int io_nsignals, io_count, intr_count;
+
+extern void signal_usr1(int sig);
+
+int tracing_pid = -1;
+
+int tracer(int (*init_proc)(void *), void *sp)
+{
+	void *task = NULL;
+	unsigned long eip = 0;
+	int status, pid = 0, sig = 0, cont_type, tracing = 0, op = 0;
+	int last_index, proc_id = 0, n, err, old_tracing = 0, strace = 0;
+
+	capture_signal_stack();
+	signal(SIGPIPE, SIG_IGN);
+	setup_tracer_winch();
+	tracing_pid = os_getpid();
+	printf("tracing thread pid = %d\n", tracing_pid);
+
+	pid = clone(signal_tramp, sp, CLONE_FILES | SIGCHLD, init_proc);
+	n = waitpid(pid, &status, WUNTRACED);
+	if(n < 0){
+		printf("waitpid on idle thread failed, errno = %d\n", errno);
+		exit(1);
+	}
+	if((ptrace(PTRACE_CONT, pid, 0, 0) < 0)){
+		printf("Failed to continue idle thread, errno = %d\n", errno);
+		exit(1);
+	}
+
+	signal(SIGSEGV, (sighandler_t) tracer_segv);
+	signal(SIGUSR1, signal_usr1);
+	set_handler(SIGINT, last_ditch_exit, SA_ONESHOT | SA_NODEFER, -1);
+	set_handler(SIGTERM, last_ditch_exit, SA_ONESHOT | SA_NODEFER, -1);
+	set_handler(SIGHUP, last_ditch_exit, SA_ONESHOT | SA_NODEFER, -1);
+	if(debug_trace){
+		printf("Tracing thread pausing to be attached\n");
+		stop();
+	}
+	if(debug){
+		if(gdb_pid != -1) 
+			debugger_pid = attach_debugger(pid, gdb_pid, 1);
+		else debugger_pid = init_ptrace_proxy(pid, 1, debug_stop);
+		if(debug_parent){
+			debugger_parent = os_process_parent(debugger_pid);
+			init_parent_proxy(debugger_parent);
+			err = attach(debugger_parent);
+			if(err){
+				printf("Failed to attach debugger parent %d, "
+				       "errno = %d\n", debugger_parent, err);
+				debugger_parent = -1;
+			}
+			else {
+				if(ptrace(PTRACE_SYSCALL, debugger_parent, 
+					  0, 0) < 0){
+					printf("Failed to continue debugger "
+					       "parent, errno = %d\n", errno);
+					debugger_parent = -1;
+				}
+			}
+		}
+	}
+	set_cmdline("(tracing thread)");
+	while(1){
+		if((pid = waitpid(-1, &status, WUNTRACED)) <= 0){
+			if(errno != ECHILD){
+				printf("wait failed - errno = %d\n", errno);
+			}
+			continue;
+		}
+		if(pid == debugger_pid){
+			int cont = 0;
+
+			if(WIFEXITED(status) || WIFSIGNALED(status))
+				debugger_pid = -1;
+			/* XXX Figure out how to deal with gdb and SMP */
+			else cont = debugger_signal(status, cpu_tasks[0].pid);
+			if(cont == PTRACE_SYSCALL) strace = 1;
+			continue;
+		}
+		else if(pid == debugger_parent){
+			debugger_parent_signal(status, pid);
+			continue;
+		}
+		nsignals++;
+		if(WIFEXITED(status)) ;
+#ifdef notdef
+		{
+			printf("Child %d exited with status %d\n", pid, 
+			       WEXITSTATUS(status));
+		}
+#endif
+		else if(WIFSIGNALED(status)){
+			sig = WTERMSIG(status);
+			if(sig != 9){
+				printf("Child %d exited with signal %d\n", pid,
+				       sig);
+			}
+		}
+		else if(WIFSTOPPED(status)){
+			proc_id = pid_to_processor_id(pid);
+			sig = WSTOPSIG(status);
+			if(signal_index[proc_id] == 1024){
+				signal_index[proc_id] = 0;
+				last_index = 1023;
+			}
+			else last_index = signal_index[proc_id] - 1;
+			if(((sig == SIGPROF) || (sig == SIGVTALRM) || 
+			    (sig == SIGALRM)) &&
+			   (signal_record[proc_id][last_index].signal == sig)&&
+			   (signal_record[proc_id][last_index].pid == pid))
+				signal_index[proc_id] = last_index;
+			signal_record[proc_id][signal_index[proc_id]].pid = pid;
+			gettimeofday(&signal_record[proc_id][signal_index[proc_id]].time, NULL);
+			eip = ptrace(PTRACE_PEEKUSER, pid, PT_IP_OFFSET, 0);
+			signal_record[proc_id][signal_index[proc_id]].addr = eip;
+			signal_record[proc_id][signal_index[proc_id]++].signal = sig;
+			
+			if(proc_id == -1){
+				sleeping_process_signal(pid, sig);
+				continue;
+			}
+
+			task = cpu_tasks[proc_id].task;
+			tracing = is_tracing(task);
+			old_tracing = tracing;
+
+			switch(sig){
+			case SIGUSR1:
+				sig = 0;
+				op = do_proc_op(task, proc_id);
+				switch(op){
+				case OP_TRACE_ON:
+					arch_leave_kernel(task, pid);
+					tracing = 1;
+					break;
+				case OP_REBOOT:
+				case OP_HALT:
+					unmap_physmem();
+					kmalloc_ok = 0;
+					ptrace(PTRACE_KILL, pid, 0, 0);
+					return(op == OP_REBOOT);
+				case OP_NONE:
+					printf("Detaching pid %d\n", pid);
+					detach(pid, SIGSTOP);
+					continue;
+				default:
+					break;
+				}
+				/* OP_EXEC switches host processes on us,
+				 * we want to continue the new one.
+				 */
+				pid = cpu_tasks[proc_id].pid;
+				break;
+			case SIGTRAP:
+				if(!tracing && (debugger_pid != -1)){
+					child_signal(pid, status);
+					continue;
+				}
+				tracing = 0;
+				if(do_syscall(task, pid)) sig = SIGUSR2;
+				else clear_singlestep(task);
+				break;
+			case SIGPROF:
+				if(tracing) sig = 0;
+				break;
+			case SIGCHLD:
+			case SIGHUP:
+				sig = 0;
+				break;
+			case SIGSEGV:
+			case SIGIO:
+			case SIGALRM:
+			case SIGVTALRM:
+			case SIGFPE:
+			case SIGBUS:
+			case SIGILL:
+			case SIGWINCH:
+			default:
+				tracing = 0;
+				break;
+			}
+			set_tracing(task, tracing);
+
+			if(!tracing && old_tracing)
+				arch_enter_kernel(task, pid);
+
+			if(!tracing && (debugger_pid != -1) && (sig != 0) &&
+				(sig != SIGALRM) && (sig != SIGVTALRM) &&
+				(sig != SIGSEGV) && (sig != SIGTRAP) &&
+				(sig != SIGUSR2) && (sig != SIGIO)){
+				child_signal(pid, status);
+				continue;
+			}
+
+			if(tracing){
+				if(singlestepping(task))
+					cont_type = PTRACE_SINGLESTEP;
+				else cont_type = PTRACE_SYSCALL;
+			}
+			else cont_type = PTRACE_CONT;
+
+			if((cont_type == PTRACE_CONT) && 
+			   (debugger_pid != -1) && strace)
+				cont_type = PTRACE_SYSCALL;
+
+			if(ptrace(cont_type, pid, 0, sig) != 0){
+				tracer_panic("ptrace failed to continue "
+					     "process - errno = %d\n", 
+					     errno);
+			}
+		}
+	}
+	return(0);
+}
+
+static int __init uml_debug_setup(char *line, int *add)
+{
+	char *next;
+
+	debug = 1;
+	*add = 0;
+	if(*line != '=') return(0);
+	line++;
+
+	while(line != NULL){
+		next = strchr(line, ',');
+		if(next) *next++ = '\0';
+		
+		if(!strcmp(line, "go"))	debug_stop = 0;
+		else if(!strcmp(line, "parent")) debug_parent = 1;
+		else printk("Unknown debug option : '%s'\n", line);
+
+		line = next;
+	}
+	return(0);
+}
+
+__uml_setup("debug", uml_debug_setup,
+"debug\n"
+"    Starts up the kernel under the control of gdb. See the \n"
+"    kernel debugging tutorial and the debugging session pages\n"
+"    at http://user-mode-linux.sourceforge.net/ for more information.\n\n"
+);
+
+static int __init uml_debugtrace_setup(char *line, int *add)
+{
+	debug_trace = 1;
+	return 0;
+}
+__uml_setup("debugtrace", uml_debugtrace_setup,
+"debugtrace\n"
+"    Causes the tracing thread to pause until it is attached by a\n"
+"    debugger and continued.  This is mostly for debugging crashes\n"
+"    early during boot, and should be pretty much obsoleted by\n"
+"    the debug switch.\n\n"
+);
+
+static int __init uml_honeypot_setup(char *line, int *add)
+{
+	jail_setup("", add);
+	honeypot = 1;
+	return 0;
+}
+__uml_setup("honeypot", uml_honeypot_setup, 
+"honeypot\n"
+"    This makes UML put process stacks in the same location as they are\n"
+"    on the host, allowing expoits such as stack smashes to work against\n"
+"    UML.  This implies 'jail'.\n\n"
+);
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */