Commit 28a35716 authored by Michel Lespinasse's avatar Michel Lespinasse Committed by Linus Torvalds
Browse files

mm: use long type for page counts in mm_populate() and get_user_pages() 



Use long type for page counts in mm_populate() so as to avoid integer
overflow when running the following test code:

int main(void) {
  void *p = mmap(NULL, 0x100000000000, PROT_READ,
                 MAP_PRIVATE | MAP_ANON, -1, 0);
  printf("p: %p\n", p);
  mlockall(MCL_CURRENT);
  printf("done\n");
  return 0;
}

Signed-off-by: default avatarMichel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent e0fb5815

include/linux/hugetlb.h

+3 −3
Original line number Diff line number Diff line
@@ -43,9 +43,9 @@ int hugetlb_mempolicy_sysctl_handler(struct ctl_table *, int, 
#endif



int copy_hugetlb_page_range(struct mm_struct *, struct mm_struct *, struct vm_area_struct *);

int follow_hugetlb_page(struct mm_struct *, struct vm_area_struct *,

long follow_hugetlb_page(struct mm_struct *, struct vm_area_struct *,

			 struct page **, struct vm_area_struct **,

			unsigned long *, int *, int, unsigned int flags);

			 unsigned long *, unsigned long *, long, unsigned int);

void unmap_hugepage_range(struct vm_area_struct *,

			  unsigned long, unsigned long, struct page *);

void __unmap_hugepage_range_final(struct mmu_gather *tlb,

include/linux/mm.h

+8 −7
Original line number Diff line number Diff line
@@ -1013,13 +1013,14 @@ extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void * 
extern int access_remote_vm(struct mm_struct *mm, unsigned long addr,

		void *buf, int len, int write);



int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,

		     unsigned long start, int len, unsigned int foll_flags,

		     struct page **pages, struct vm_area_struct **vmas,

		     int *nonblocking);

int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,

			unsigned long start, int nr_pages, int write, int force,

			struct page **pages, struct vm_area_struct **vmas);

long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,

		      unsigned long start, unsigned long nr_pages,

		      unsigned int foll_flags, struct page **pages,

		      struct vm_area_struct **vmas, int *nonblocking);

long get_user_pages(struct task_struct *tsk, struct mm_struct *mm,

		    unsigned long start, unsigned long nr_pages,

		    int write, int force, struct page **pages,

		    struct vm_area_struct **vmas);

int get_user_pages_fast(unsigned long start, int nr_pages, int write,

			struct page **pages);

struct kvec;

mm/hugetlb.c

+6 −6
Original line number Diff line number Diff line
@@ -2920,14 +2920,14 @@ follow_huge_pud(struct mm_struct *mm, unsigned long address, 
	return NULL;

}



int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,

long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,

			 struct page **pages, struct vm_area_struct **vmas,

			unsigned long *position, int *length, int i,

			unsigned int flags)

			 unsigned long *position, unsigned long *nr_pages,

			 long i, unsigned int flags)

{

	unsigned long pfn_offset;

	unsigned long vaddr = *position;

	int remainder = *length;

	unsigned long remainder = *nr_pages;

	struct hstate *h = hstate_vma(vma);



	spin_lock(&mm->page_table_lock);
@@ -2997,7 +2997,7 @@ same_page: 
		}

	}

	spin_unlock(&mm->page_table_lock);

	*length = remainder;

	*nr_pages = remainder;

	*position = vaddr;



	return i ? i : -EFAULT;

mm/memory.c

+9 −9
Original line number Diff line number Diff line
@@ -1677,15 +1677,15 @@ static inline int stack_guard_page(struct vm_area_struct *vma, unsigned long add 
 * instead of __get_user_pages. __get_user_pages should be used only if

 * you need some special @gup_flags.

 */

int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,

		     unsigned long start, int nr_pages, unsigned int gup_flags,

		     struct page **pages, struct vm_area_struct **vmas,

		     int *nonblocking)

long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,

		unsigned long start, unsigned long nr_pages,

		unsigned int gup_flags, struct page **pages,

		struct vm_area_struct **vmas, int *nonblocking)

{

	int i;

	long i;

	unsigned long vm_flags;



	if (nr_pages <= 0)

	if (!nr_pages)

		return 0;



	VM_BUG_ON(!!pages != !!(gup_flags & FOLL_GET));
@@ -1981,9 +1981,9 @@ int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm, 
 *

 * See also get_user_pages_fast, for performance critical applications.

 */

int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,

		unsigned long start, int nr_pages, int write, int force,

		struct page **pages, struct vm_area_struct **vmas)

long get_user_pages(struct task_struct *tsk, struct mm_struct *mm,

		unsigned long start, unsigned long nr_pages, int write,

		int force, struct page **pages, struct vm_area_struct **vmas)

{

	int flags = FOLL_TOUCH;

mm/mlock.c

+2 −2
Original line number Diff line number Diff line
@@ -160,7 +160,7 @@ long __mlock_vma_pages_range(struct vm_area_struct *vma, 
{

	struct mm_struct *mm = vma->vm_mm;

	unsigned long addr = start;

	int nr_pages = (end - start) / PAGE_SIZE;

	unsigned long nr_pages = (end - start) / PAGE_SIZE;

	int gup_flags;



	VM_BUG_ON(start & ~PAGE_MASK);
@@ -382,7 +382,7 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors) 
	unsigned long end, nstart, nend;

	struct vm_area_struct *vma = NULL;

	int locked = 0;

	int ret = 0;

	long ret = 0;



	VM_BUG_ON(start & ~PAGE_MASK);

	VM_BUG_ON(len != PAGE_ALIGN(len));

CRA Git | Maintained and supported by SUSTech CRA and CCSE