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#include <sched.h>
#include <signal.h>
#include <sys/mman.h>
#include <sys/time.h>
#include <asm/unistd.h>
#include <asm/page.h>
#include "ptrace_user.h"
#include "skas.h"
#include "stub-data.h"
#include "uml-config.h"
#include "sysdep/stub.h"
#include "kern_constants.h"
/* This is in a separate file because it needs to be compiled with any
* extraneous gcc flags (-pg, -fprofile-arcs, -ftest-coverage) disabled
*
* Use UM_KERN_PAGE_SIZE instead of PAGE_SIZE because that calls getpagesize
* on some systems.
*/
#define STUB_DATA(field) (((struct stub_data *) UML_CONFIG_STUB_DATA)->field)
void __attribute__ ((__section__ (".__syscall_stub")))
stub_clone_handler(void)
{
long err;
err = stub_syscall2(__NR_clone, CLONE_PARENT | CLONE_FILES | SIGCHLD,
UML_CONFIG_STUB_DATA + UM_KERN_PAGE_SIZE / 2 -
sizeof(void *));
if(err != 0)
goto out;
err = stub_syscall4(__NR_ptrace, PTRACE_TRACEME, 0, 0, 0);
if(err)
goto out;
err = stub_syscall3(__NR_setitimer, ITIMER_VIRTUAL,
(long) &STUB_DATA(timer), 0);
if(err)
goto out;
err = stub_syscall6(STUB_MMAP_NR, UML_CONFIG_STUB_DATA,
UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE,
MAP_FIXED | MAP_SHARED, STUB_DATA(fd),
STUB_DATA(offset));
out:
/* save current result. Parent: pid; child: retcode of mmap */
STUB_DATA(err) = err;
trap_myself();
}
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