diff options
Diffstat (limited to 'mm/fremap.c')
| -rw-r--r-- | mm/fremap.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/mm/fremap.c b/mm/fremap.c index 46f5dacf90a2..ec520c7b28df 100644 --- a/mm/fremap.c +++ b/mm/fremap.c | |||
| @@ -125,7 +125,6 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size, | |||
| 125 | { | 125 | { |
| 126 | struct mm_struct *mm = current->mm; | 126 | struct mm_struct *mm = current->mm; |
| 127 | struct address_space *mapping; | 127 | struct address_space *mapping; |
| 128 | unsigned long end = start + size; | ||
| 129 | struct vm_area_struct *vma; | 128 | struct vm_area_struct *vma; |
| 130 | int err = -EINVAL; | 129 | int err = -EINVAL; |
| 131 | int has_write_lock = 0; | 130 | int has_write_lock = 0; |
| @@ -142,6 +141,10 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size, | |||
| 142 | if (start + size <= start) | 141 | if (start + size <= start) |
| 143 | return err; | 142 | return err; |
| 144 | 143 | ||
| 144 | /* Does pgoff wrap? */ | ||
| 145 | if (pgoff + (size >> PAGE_SHIFT) < pgoff) | ||
| 146 | return err; | ||
| 147 | |||
| 145 | /* Can we represent this offset inside this architecture's pte's? */ | 148 | /* Can we represent this offset inside this architecture's pte's? */ |
| 146 | #if PTE_FILE_MAX_BITS < BITS_PER_LONG | 149 | #if PTE_FILE_MAX_BITS < BITS_PER_LONG |
| 147 | if (pgoff + (size >> PAGE_SHIFT) >= (1UL << PTE_FILE_MAX_BITS)) | 150 | if (pgoff + (size >> PAGE_SHIFT) >= (1UL << PTE_FILE_MAX_BITS)) |
| @@ -168,7 +171,7 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size, | |||
| 168 | if (!(vma->vm_flags & VM_CAN_NONLINEAR)) | 171 | if (!(vma->vm_flags & VM_CAN_NONLINEAR)) |
| 169 | goto out; | 172 | goto out; |
| 170 | 173 | ||
| 171 | if (end <= start || start < vma->vm_start || end > vma->vm_end) | 174 | if (start < vma->vm_start || start + size > vma->vm_end) |
| 172 | goto out; | 175 | goto out; |
| 173 | 176 | ||
| 174 | /* Must set VM_NONLINEAR before any pages are populated. */ | 177 | /* Must set VM_NONLINEAR before any pages are populated. */ |
