Scare Crowe 2a709f28fa Auto exploit mitigation feature
* 0day explit mitigation
* Memory corruption prevention
* Privilege escalation prevention
* Buffer over flow prevention
* File System corruption defense
* Thread escape prevention

This may very well be the most intensive inclusion to BrooklynR. This will not be part of an x86 suite nor it will be released as tool kit. The security core toolkit will remain part of kernel base.
2021-11-13 09:26:51 +05:00

109 lines
2.8 KiB
C

#ifndef __LINUX_KSM_H
#define __LINUX_KSM_H
/*
* Memory merging support.
*
* This code enables dynamic sharing of identical pages found in different
* memory areas, even if they are not shared by fork().
*/
#include <linux/bitops.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#include <linux/rmap.h>
#include <linux/sched.h>
struct stable_node;
struct mem_cgroup;
#ifdef CONFIG_KSM
int ksm_madvise(struct vm_area_struct *vma, unsigned long start,
unsigned long end, int advice, unsigned long *vm_flags);
int __ksm_enter(struct mm_struct *mm);
void __ksm_exit(struct mm_struct *mm);
static inline int ksm_fork(struct mm_struct *mm, struct mm_struct *oldmm)
{
if (test_bit(MMF_VM_MERGEABLE, &oldmm->flags))
return __ksm_enter(mm);
return 0;
}
static inline void ksm_exit(struct mm_struct *mm)
{
if (test_bit(MMF_VM_MERGEABLE, &mm->flags))
__ksm_exit(mm);
}
static inline struct stable_node *page_stable_node(struct page *page)
{
return PageKsm(page) ? page_rmapping(page) : NULL;
}
static inline void set_page_stable_node(struct page *page,
struct stable_node *stable_node)
{
page->mapping = (void *)((unsigned long)stable_node | PAGE_MAPPING_KSM);
}
/*
* When do_swap_page() first faults in from swap what used to be a KSM page,
* no problem, it will be assigned to this vma's anon_vma; but thereafter,
* it might be faulted into a different anon_vma (or perhaps to a different
* offset in the same anon_vma). do_swap_page() cannot do all the locking
* needed to reconstitute a cross-anon_vma KSM page: for now it has to make
* a copy, and leave remerging the pages to a later pass of ksmd.
*
* We'd like to make this conditional on vma->vm_flags & VM_MERGEABLE,
* but what if the vma was unmerged while the page was swapped out?
*/
struct page *ksm_might_need_to_copy(struct page *page,
struct vm_area_struct *vma, unsigned long address);
int rmap_walk_ksm(struct page *page, struct rmap_walk_control *rwc);
void ksm_migrate_page(struct page *newpage, struct page *oldpage);
#else /* !CONFIG_KSM */
static inline int ksm_fork(struct mm_struct *mm, struct mm_struct *oldmm)
{
return 0;
}
static inline void ksm_exit(struct mm_struct *mm)
{
}
#ifdef CONFIG_MMU
static inline int ksm_madvise(struct vm_area_struct *vma, unsigned long start,
unsigned long end, int advice, unsigned long *vm_flags)
{
return 0;
}
static inline struct page *ksm_might_need_to_copy(struct page *page,
struct vm_area_struct *vma, unsigned long address)
{
return page;
}
static inline int page_referenced_ksm(struct page *page,
struct mem_cgroup *memcg, unsigned long *vm_flags)
{
return 0;
}
static inline int rmap_walk_ksm(struct page *page,
struct rmap_walk_control *rwc)
{
return 0;
}
static inline void ksm_migrate_page(struct page *newpage, struct page *oldpage)
{
}
#endif /* CONFIG_MMU */
#endif /* !CONFIG_KSM */
#endif /* __LINUX_KSM_H */