diff options
| -rw-r--r-- | mm/mremap.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/mm/mremap.c b/mm/mremap.c index 90e422c9f41..9d0753983dc 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -27,6 +27,10 @@ #include "internal.h" +#ifndef arch_mmap_check +#define arch_mmap_check(addr, len, flags) (0) +#endif + static pmd_t *get_old_pmd(struct mm_struct *mm, unsigned long addr) { pgd_t *pgd; @@ -368,12 +372,17 @@ out: static int vma_expandable(struct vm_area_struct *vma, unsigned long delta) { + unsigned long end = vma->vm_end + delta; unsigned long max_addr = TASK_SIZE; if (vma->vm_next) max_addr = vma->vm_next->vm_start; - if (max_addr - vma->vm_end < delta) + if (max_addr < end || end < vma->vm_end) + return 0; + if (arch_mmap_check(vma->vm_start, end - vma->vm_start, MAP_FIXED)) + return 0; + if (get_unmapped_area(NULL, vma->vm_start, end - vma->vm_start, + 0, MAP_FIXED) & ~PAGE_MASK) return 0; - /* we need to do arch-specific checks here */ return 1; } |