132 lines
2.7 KiB
C
132 lines
2.7 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
|
|
#include "shared.h"
|
|
|
|
|
|
bool fail_prealloc;
|
|
unsigned long mmap_min_addr = CONFIG_DEFAULT_MMAP_MIN_ADDR;
|
|
unsigned long dac_mmap_min_addr = CONFIG_DEFAULT_MMAP_MIN_ADDR;
|
|
unsigned long stack_guard_gap = 256UL<<PAGE_SHIFT;
|
|
|
|
const struct vm_operations_struct vma_dummy_vm_ops;
|
|
struct anon_vma dummy_anon_vma;
|
|
struct task_struct __current;
|
|
|
|
struct vm_area_struct *alloc_vma(struct mm_struct *mm,
|
|
unsigned long start, unsigned long end,
|
|
pgoff_t pgoff, vm_flags_t vm_flags)
|
|
{
|
|
struct vm_area_struct *vma = vm_area_alloc(mm);
|
|
|
|
if (vma == NULL)
|
|
return NULL;
|
|
|
|
vma->vm_start = start;
|
|
vma->vm_end = end;
|
|
vma->vm_pgoff = pgoff;
|
|
vm_flags_reset(vma, vm_flags);
|
|
vma_assert_detached(vma);
|
|
|
|
return vma;
|
|
}
|
|
|
|
void detach_free_vma(struct vm_area_struct *vma)
|
|
{
|
|
vma_mark_detached(vma);
|
|
vm_area_free(vma);
|
|
}
|
|
|
|
struct vm_area_struct *alloc_and_link_vma(struct mm_struct *mm,
|
|
unsigned long start, unsigned long end,
|
|
pgoff_t pgoff, vm_flags_t vm_flags)
|
|
{
|
|
struct vm_area_struct *vma = alloc_vma(mm, start, end, pgoff, vm_flags);
|
|
|
|
if (vma == NULL)
|
|
return NULL;
|
|
|
|
if (attach_vma(mm, vma)) {
|
|
detach_free_vma(vma);
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Reset this counter which we use to track whether writes have
|
|
* begun. Linking to the tree will have caused this to be incremented,
|
|
* which means we will get a false positive otherwise.
|
|
*/
|
|
vma->vm_lock_seq = UINT_MAX;
|
|
|
|
return vma;
|
|
}
|
|
|
|
void reset_dummy_anon_vma(void)
|
|
{
|
|
dummy_anon_vma.was_cloned = false;
|
|
dummy_anon_vma.was_unlinked = false;
|
|
}
|
|
|
|
int cleanup_mm(struct mm_struct *mm, struct vma_iterator *vmi)
|
|
{
|
|
struct vm_area_struct *vma;
|
|
int count = 0;
|
|
|
|
fail_prealloc = false;
|
|
reset_dummy_anon_vma();
|
|
|
|
vma_iter_set(vmi, 0);
|
|
for_each_vma(*vmi, vma) {
|
|
detach_free_vma(vma);
|
|
count++;
|
|
}
|
|
|
|
mtree_destroy(&mm->mm_mt);
|
|
mm->map_count = 0;
|
|
return count;
|
|
}
|
|
|
|
bool vma_write_started(struct vm_area_struct *vma)
|
|
{
|
|
int seq = vma->vm_lock_seq;
|
|
|
|
/* We reset after each check. */
|
|
vma->vm_lock_seq = UINT_MAX;
|
|
|
|
/* The vma_start_write() stub simply increments this value. */
|
|
return seq > -1;
|
|
}
|
|
|
|
void __vma_set_dummy_anon_vma(struct vm_area_struct *vma,
|
|
struct anon_vma_chain *avc, struct anon_vma *anon_vma)
|
|
{
|
|
vma->anon_vma = anon_vma;
|
|
INIT_LIST_HEAD(&vma->anon_vma_chain);
|
|
list_add(&avc->same_vma, &vma->anon_vma_chain);
|
|
avc->anon_vma = vma->anon_vma;
|
|
}
|
|
|
|
void vma_set_dummy_anon_vma(struct vm_area_struct *vma,
|
|
struct anon_vma_chain *avc)
|
|
{
|
|
__vma_set_dummy_anon_vma(vma, avc, &dummy_anon_vma);
|
|
}
|
|
|
|
struct task_struct *get_current(void)
|
|
{
|
|
return &__current;
|
|
}
|
|
|
|
unsigned long rlimit(unsigned int limit)
|
|
{
|
|
return (unsigned long)-1;
|
|
}
|
|
|
|
void vma_set_range(struct vm_area_struct *vma,
|
|
unsigned long start, unsigned long end,
|
|
pgoff_t pgoff)
|
|
{
|
|
vma->vm_start = start;
|
|
vma->vm_end = end;
|
|
vma->vm_pgoff = pgoff;
|
|
}
|