From 28a35716d317980ae9bc2ff2f84c33a3cda9e884 Mon Sep 17 00:00:00 2001 From: Michel Lespinasse Date: Fri, 22 Feb 2013 16:35:55 -0800 Subject: [PATCH] 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 Cc: Andrea Arcangeli Cc: Rik van Riel Cc: Mel Gorman Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/hugetlb.h | 6 +++--- include/linux/mm.h | 15 ++++++++------- mm/hugetlb.c | 12 ++++++------ mm/memory.c | 18 +++++++++--------- mm/mlock.c | 4 ++-- mm/nommu.c | 15 ++++++++------- 6 files changed, 36 insertions(+), 34 deletions(-) diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 0c80d3f57a5b..eedc334fb6f5 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -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 *, - 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 97da0302cf51..87b0ef253607 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -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; diff --git a/mm/hugetlb.c b/mm/hugetlb.c index e14a8c79a1eb..cdb64e4d238a 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -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, - 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 @@ same_page: } } 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 7bd22a621817..bc929dbad215 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -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; diff --git a/mm/mlock.c b/mm/mlock.c index 38db3b094105..e6638f565d42 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -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)); diff --git a/mm/nommu.c b/mm/nommu.c index 87854a55829d..6ab706608492 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -140,10 +140,10 @@ unsigned int kobjsize(const void *objp) 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 @@ finish_or_fault: * 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;