1 /* 2 * Copyright (C) 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) 3 * Licensed under the GPL 4 */ 5 6 #include <signal.h> 7 #include <sched.h> 8 #include <asm/unistd.h> 9 #include <sys/time.h> 10 #include "as-layout.h" 11 #include "kern_constants.h" 12 #include "ptrace_user.h" 13 #include "stub-data.h" 14 #include "sysdep/stub.h" 15 16 /* 17 * This is in a separate file because it needs to be compiled with any 18 * extraneous gcc flags (-pg, -fprofile-arcs, -ftest-coverage) disabled 19 * 20 * Use UM_KERN_PAGE_SIZE instead of PAGE_SIZE because that calls getpagesize 21 * on some systems. 22 */ 23 24 void __attribute__ ((__section__ (".__syscall_stub"))) 25 stub_clone_handler(void) 26 { 27 struct stub_data *data = (struct stub_data *) STUB_DATA; 28 long err; 29 30 err = stub_syscall2(__NR_clone, CLONE_PARENT | CLONE_FILES | SIGCHLD, 31 STUB_DATA + UM_KERN_PAGE_SIZE / 2 - sizeof(void *)); 32 if (err != 0) 33 goto out; 34 35 err = stub_syscall4(__NR_ptrace, PTRACE_TRACEME, 0, 0, 0); 36 if (err) 37 goto out; 38 39 err = stub_syscall3(__NR_setitimer, ITIMER_VIRTUAL, 40 (long) &data->timer, 0); 41 if (err) 42 goto out; 43 44 remap_stack(data->fd, data->offset); 45 goto done; 46 47 out: 48 /* 49 * save current result. 50 * Parent: pid; 51 * child: retcode of mmap already saved and it jumps around this 52 * assignment 53 */ 54 data->err = err; 55 done: 56 trap_myself(); 57 } 58