/* Setup a VMA at program startup for the vsyscall page */
int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp,
unsigned long map_address)
{
struct mm_struct *mm = current->mm;
unsigned long addr = map_address;
int ret = 0;
bool compat;
unsigned long flags;
if (vdso_enabled == VDSO_DISABLED && map_address == 0) {
current->mm->context.vdso = NULL;
return 0;
}
flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYEXEC | VM_MAYWRITE |
mm->def_flags;
ret = -ENOMEM;
if (ub_memory_charge(mm, PAGE_SIZE, flags, NULL, UB_SOFT))
goto err_charge;
down_write(&mm->mmap_sem);
/* Test compat mode once here, in case someone
changes it via sysctl */
compat = (vdso_enabled == VDSO_COMPAT);
map_compat_vdso(compat);
if (!compat || map_address) {
addr = get_unmapped_area_prot(NULL, addr, PAGE_SIZE, 0, 0, 1);
if (IS_ERR_VALUE(addr)) {
ret = addr;
goto up_fail;
}
} else
addr = VDSO_HIGH_BASE;
current->mm->context.vdso = (void *)addr;
if (compat_uses_vma || !compat || map_address) {
struct page **pages = uts_prep_vdso_pages_locked(compat);
if (IS_ERR(pages)) {
ret = PTR_ERR(pages);
goto up_fail;
}
/*
* MAYWRITE to allow gdb to COW and set breakpoints
*/
ret = install_special_mapping(mm, addr, PAGE_SIZE,
VM_READ|VM_EXEC|
VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
pages);
if (ret)
goto up_fail;
}
current_thread_info()->sysenter_return =
VDSO32_SYMBOL(addr, SYSENTER_RETURN);
up_fail:
if (ret)
current->mm->context.vdso = NULL;
up_write(&mm->mmap_sem);
if (ret < 0)
ub_memory_uncharge(mm, PAGE_SIZE, flags, NULL);
err_charge:
return ret;
}
/* Setup a VMA at program startup for the vsyscall page */
int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp,
unsigned long map_address)
{
struct mm_struct *mm = current->mm;
unsigned long addr = map_address;
int ret = 0;
bool compat;
unsigned long flags;
if (vdso_enabled == VDSO_DISABLED && map_address == 0) {
current->mm->context.vdso = NULL;
return 0;
}
flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYEXEC | VM_MAYWRITE |
mm->def_flags;
ret = -ENOMEM;
if (ub_memory_charge(mm, PAGE_SIZE, flags, NULL, UB_SOFT))
goto err_charge;
down_write(&mm->mmap_sem);
/* Test compat mode once here, in case someone
changes it via sysctl */
compat = (vdso_enabled == VDSO_COMPAT);
map_compat_vdso(compat);
if (!compat || map_address) {
addr = get_unmapped_area_prot(NULL, addr, PAGE_SIZE, 0, 0, 1);
if (IS_ERR_VALUE(addr)) {
ret = addr;
goto up_fail;
}
} else
addr = VDSO_HIGH_BASE;
current->mm->context.vdso = (void *)addr;
if (compat_uses_vma || !compat || map_address) {
/*
* MAYWRITE to allow gdb to COW and set breakpoints
*
* Make sure the vDSO gets into every core dump.
* Dumping its contents makes post-mortem fully
* interpretable later without matching up the same
* kernel and hardware config to see what PC values
* meant.
*/
ret = install_special_mapping(mm, addr, PAGE_SIZE,
VM_READ|VM_EXEC|
VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
VM_ALWAYSDUMP,
vdso32_pages);
if (ret)
goto up_fail;
}
current_thread_info()->sysenter_return =
VDSO32_SYMBOL(addr, SYSENTER_RETURN);
up_fail:
if (ret)
current->mm->context.vdso = NULL;
up_write(&mm->mmap_sem);
if (ret < 0)
ub_memory_uncharge(mm, PAGE_SIZE, flags, NULL);
err_charge:
return ret;
}
