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: Michel 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 0c80d3f..eedc334 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -43,9 +43,9 @@
#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 *,
- struct page **, struct vm_area_struct **,
- unsigned long *, int *, int, unsigned int flags);
+long follow_hugetlb_page(struct mm_struct *, struct vm_area_struct *,
+ struct page **, struct vm_area_struct **,
+ 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,
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 97da030..87b0ef2 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1013,13 +1013,14 @@
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;
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index e14a8c7..cdb64e4 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2920,14 +2920,14 @@
return NULL;
}
-int 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)
+long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
+ struct page **pages, struct vm_area_struct **vmas,
+ 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 @@
}
}
spin_unlock(&mm->page_table_lock);
- *length = remainder;
+ *nr_pages = remainder;
*position = vaddr;
return i ? i : -EFAULT;
diff --git a/mm/memory.c b/mm/memory.c
index 7bd22a6..bc929db 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1677,15 +1677,15 @@
* 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 @@
*
* 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;
diff --git a/mm/mlock.c b/mm/mlock.c
index 38db3b0..e6638f5 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -160,7 +160,7 @@
{
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 @@
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));
diff --git a/mm/nommu.c b/mm/nommu.c
index 87854a5..6ab7066 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -140,10 +140,10 @@
return PAGE_SIZE << compound_order(page);
}
-int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
- unsigned long start, int nr_pages, unsigned int foll_flags,
- struct page **pages, struct vm_area_struct **vmas,
- int *retry)
+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)
{
struct vm_area_struct *vma;
unsigned long vm_flags;
@@ -190,9 +190,10 @@
* slab page or a secondary page from a compound page
* - don't permit access to VMAs that don't support it, such as I/O mappings
*/
-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 = 0;