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