diff options
| author | James Morris <jmorris@namei.org> | 2011-04-19 21:32:41 +1000 |
|---|---|---|
| committer | James Morris <jmorris@namei.org> | 2011-04-19 21:32:41 +1000 |
| commit | d4ab4e6a23f805abb8fc3cc34525eec3788aeca1 (patch) | |
| tree | eefd82c155bc27469a85667d759cd90facf4a6e3 /mm/mremap.c | |
| parent | c0fa797ae6cd02ff87c0bfe0d509368a3b45640e (diff) | |
| parent | 96fd2d57b8252e16dfacf8941f7a74a6119197f5 (diff) | |
Merge branch 'master'; commit 'v2.6.39-rc3' into next
Diffstat (limited to 'mm/mremap.c')
| -rw-r--r-- | mm/mremap.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/mm/mremap.c b/mm/mremap.c index 1de98d492dd..a7c1f9f9b94 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -277,9 +277,16 @@ static struct vm_area_struct *vma_to_resize(unsigned long addr, if (old_len > vma->vm_end - addr) goto Efault; - if (vma->vm_flags & (VM_DONTEXPAND | VM_PFNMAP)) { - if (new_len > old_len) + /* Need to be careful about a growing mapping */ + if (new_len > old_len) { + unsigned long pgoff; + + if (vma->vm_flags & (VM_DONTEXPAND | VM_PFNMAP)) goto Efault; + pgoff = (addr - vma->vm_start) >> PAGE_SHIFT; + pgoff += vma->vm_pgoff; + if (pgoff + (new_len >> PAGE_SHIFT) < pgoff) + goto Einval; } if (vma->vm_flags & VM_LOCKED) { |