1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2015 Thomas Meyer (thomas@m3y3r.de) 4 * Copyright (C) 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) 5 */ 6 7 #include <signal.h> 8 #include <sched.h> 9 #include <asm/unistd.h> 10 #include <sys/time.h> 11 #include <as-layout.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 __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 remap_stack(data->fd, data->offset); 40 goto done; 41 42 out: 43 /* 44 * save current result. 45 * Parent: pid; 46 * child: retcode of mmap already saved and it jumps around this 47 * assignment 48 */ 49 data->err = err; 50 done: 51 trap_myself(); 52 } 53