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 __attribute__ ((__section__ (".__syscall_stub"))) 25 stub_clone_handler(void) 26 { 27 int stack; 28 struct stub_data *data = (void *) ((unsigned long)&stack & ~(UM_KERN_PAGE_SIZE - 1)); 29 long err; 30 31 err = stub_syscall2(__NR_clone, CLONE_PARENT | CLONE_FILES | SIGCHLD, 32 (unsigned long)data + UM_KERN_PAGE_SIZE / 2 - sizeof(void *)); 33 if (err) { 34 data->parent_err = err; 35 goto done; 36 } 37 38 err = stub_syscall4(__NR_ptrace, PTRACE_TRACEME, 0, 0, 0); 39 if (err) { 40 data->child_err = err; 41 goto done; 42 } 43 44 remap_stack_and_trap(); 45 46 done: 47 trap_myself(); 48 } 49