int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
{
struct mm_struct *mm = current->mm;
unsigned long addr;
int ret;
if (!vdso_enabled)
return 0;
down_write(&mm->mmap_sem);
addr = vdso_addr(mm->start_stack, vdso_size);
addr = get_unmapped_area(NULL, addr, vdso_size, 0, 0);
if (IS_ERR_VALUE(addr)) {
ret = addr;
goto up_fail;
}
current->mm->context.vdso = (void *)addr;
ret = install_special_mapping(mm, addr, vdso_size,
VM_READ|VM_EXEC|
VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
VM_ALWAYSDUMP,
vdso_pages);
if (ret) {
current->mm->context.vdso = NULL;
goto up_fail;
}
up_fail:
up_write(&mm->mmap_sem);
return ret;
}
int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
{
int ret;
unsigned long addr;
struct mm_struct *mm = current->mm;
down_write(&mm->mmap_sem);
addr = vdso_addr(mm->start_stack);
addr = get_unmapped_area(NULL, addr, PAGE_SIZE, 0, 0);
if (IS_ERR_VALUE(addr)) {
ret = addr;
goto up_fail;
}
ret = install_special_mapping(mm, addr, PAGE_SIZE,
VM_READ|VM_EXEC|
VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
&vdso_page);
if (ret)
goto up_fail;
mm->context.vdso = (void *)addr;
up_fail:
up_write(&mm->mmap_sem);
return ret;
}
/* Setup a VMA at program startup for the vsyscall page.
Not called for compat tasks */
int arch_setup_additional_pages(struct linux_binprm *bprm, int exstack)
{
struct mm_struct *mm = current->mm;
unsigned long addr;
int ret;
unsigned len = round_up(vdso_end - vdso_start, PAGE_SIZE);
if (!vdso_enabled)
return 0;
down_write(&mm->mmap_sem);
addr = vdso_addr(mm->start_stack, len);
addr = get_unmapped_area(NULL, addr, len, 0, 0);
if (IS_ERR_VALUE(addr)) {
ret = addr;
goto up_fail;
}
ret = install_special_mapping(mm, addr, len,
VM_READ|VM_EXEC|
VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
VM_ALWAYSDUMP,
vdso_pages);
if (ret)
goto up_fail;
current->mm->context.vdso = (void *)addr;
up_fail:
up_write(&mm->mmap_sem);
return ret;
}
static int map_vdso(const struct vdso_image *image, bool calculate_addr)
{
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
unsigned long addr;
int ret = 0;
static struct page *no_pages[] = {NULL};
static struct vm_special_mapping vvar_mapping = {
.name = "[vvar]",
.pages = no_pages,
};
if (calculate_addr) {
addr = vdso_addr(current->mm->start_stack,
image->sym_end_mapping);
} else {
addr = 0;
}
down_write(&mm->mmap_sem);
addr = get_unmapped_area(NULL, addr, image->sym_end_mapping, 0, 0);
if (IS_ERR_VALUE(addr)) {
ret = addr;
goto up_fail;
}
current->mm->context.vdso = (void __user *)addr;
/*
* MAYWRITE to allow gdb to COW and set breakpoints
*/
vma = _install_special_mapping(mm,
addr,
image->size,
VM_READ|VM_EXEC|
VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
&image->text_mapping);
if (IS_ERR(vma)) {
ret = PTR_ERR(vma);
goto up_fail;
}
vma = _install_special_mapping(mm,
addr + image->size,
image->sym_end_mapping - image->size,
VM_READ,
&vvar_mapping);
if (IS_ERR(vma)) {
ret = PTR_ERR(vma);
goto up_fail;
}
if (image->sym_vvar_page)
ret = remap_pfn_range(vma,
addr + image->sym_vvar_page,
__pa_symbol(&__vvar_page) >> PAGE_SHIFT,
PAGE_SIZE,
PAGE_READONLY);
if (ret)
goto up_fail;
#ifdef CONFIG_HPET_TIMER
if (hpet_address && image->sym_hpet_page) {
ret = io_remap_pfn_range(vma,
addr + image->sym_hpet_page,
hpet_address >> PAGE_SHIFT,
PAGE_SIZE,
pgprot_noncached(PAGE_READONLY));
if (ret)
goto up_fail;
}
#endif
up_fail:
if (ret)
current->mm->context.vdso = NULL;
up_write(&mm->mmap_sem);
return ret;
}
static int map_vdso(const struct vdso_image *image,
struct vm_special_mapping *vdso_mapping)
{
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
unsigned long text_start, addr = 0;
int ret = 0;
down_write(&mm->mmap_sem);
/*
* First, get an unmapped region: then randomize it, and make sure that
* region is free.
*/
if (current->flags & PF_RANDOMIZE) {
addr = get_unmapped_area(NULL, 0,
image->size - image->sym_vvar_start,
0, 0);
if (IS_ERR_VALUE(addr)) {
ret = addr;
goto up_fail;
}
addr = vdso_addr(addr, image->size - image->sym_vvar_start);
}
addr = get_unmapped_area(NULL, addr,
image->size - image->sym_vvar_start, 0, 0);
if (IS_ERR_VALUE(addr)) {
ret = addr;
goto up_fail;
}
text_start = addr - image->sym_vvar_start;
current->mm->context.vdso = (void __user *)text_start;
/*
* MAYWRITE to allow gdb to COW and set breakpoints
*/
vma = _install_special_mapping(mm,
text_start,
image->size,
VM_READ|VM_EXEC|
VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
vdso_mapping);
if (IS_ERR(vma)) {
ret = PTR_ERR(vma);
goto up_fail;
}
vma = _install_special_mapping(mm,
addr,
-image->sym_vvar_start,
VM_READ|VM_MAYREAD,
&vvar_mapping);
if (IS_ERR(vma)) {
ret = PTR_ERR(vma);
do_munmap(mm, text_start, image->size, NULL);
}
up_fail:
if (ret)
current->mm->context.vdso = NULL;
up_write(&mm->mmap_sem);
return ret;
}
