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Diffstat (limited to 'mm/mprotect.c')
-rw-r--r--mm/mprotect.c19
1 files changed, 13 insertions, 6 deletions
diff --git a/mm/mprotect.c b/mm/mprotect.c
index 57577f6..17a2b52 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -29,8 +29,9 @@ static void change_pte_range(struct mm_struct *mm, pmd_t *pmd,
unsigned long addr, unsigned long end, pgprot_t newprot)
{
pte_t *pte;
+ spinlock_t *ptl;
- pte = pte_offset_map(pmd, addr);
+ pte = pte_offset_map_lock(mm, pmd, addr, &ptl);
do {
if (pte_present(*pte)) {
pte_t ptent;
@@ -44,7 +45,7 @@ static void change_pte_range(struct mm_struct *mm, pmd_t *pmd,
lazy_mmu_prot_update(ptent);
}
} while (pte++, addr += PAGE_SIZE, addr != end);
- pte_unmap(pte - 1);
+ pte_unmap_unlock(pte - 1, ptl);
}
static inline void change_pmd_range(struct mm_struct *mm, pud_t *pud,
@@ -88,7 +89,6 @@ static void change_protection(struct vm_area_struct *vma,
BUG_ON(addr >= end);
pgd = pgd_offset(mm, addr);
flush_cache_range(vma, addr, end);
- spin_lock(&mm->page_table_lock);
do {
next = pgd_addr_end(addr, end);
if (pgd_none_or_clear_bad(pgd))
@@ -96,7 +96,6 @@ static void change_protection(struct vm_area_struct *vma,
change_pud_range(mm, pgd, addr, next, newprot);
} while (pgd++, addr = next, addr != end);
flush_tlb_range(vma, start, end);
- spin_unlock(&mm->page_table_lock);
}
static int
@@ -125,6 +124,14 @@ mprotect_fixup(struct vm_area_struct *vma, struct vm_area_struct **pprev,
* a MAP_NORESERVE private mapping to writable will now reserve.
*/
if (newflags & VM_WRITE) {
+ if (oldflags & VM_RESERVED) {
+ BUG_ON(oldflags & VM_WRITE);
+ printk(KERN_WARNING "program %s is using MAP_PRIVATE, "
+ "PROT_WRITE mprotect of VM_RESERVED memory, "
+ "which is deprecated. Please report this to "
+ "linux-kernel@vger.kernel.org\n",current->comm);
+ return -EACCES;
+ }
if (!(oldflags & (VM_ACCOUNT|VM_WRITE|VM_SHARED|VM_HUGETLB))) {
charged = nrpages;
if (security_vm_enough_memory(charged))
@@ -168,8 +175,8 @@ success:
vma->vm_flags = newflags;
vma->vm_page_prot = newprot;
change_protection(vma, start, end, newprot);
- __vm_stat_account(mm, oldflags, vma->vm_file, -nrpages);
- __vm_stat_account(mm, newflags, vma->vm_file, nrpages);
+ vm_stat_account(mm, oldflags, vma->vm_file, -nrpages);
+ vm_stat_account(mm, newflags, vma->vm_file, nrpages);
return 0;
fail:
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