diff options
| author | Andy Green <andy.green@linaro.org> | 2011-04-15 09:29:22 +0100 |
|---|---|---|
| committer | Andy Green <andy.green@linaro.org> | 2011-04-15 09:29:22 +0100 |
| commit | caa70ccf8cc719acb0540b558b4e075796778db8 (patch) | |
| tree | e8173307b04eca62168415be04e7800bdf011f80 /mm/mremap.c | |
| parent | 56d667f87e81d15d43f264007322f1179ce1722e (diff) | |
| parent | 3ec10cd8b526c6b10170c2649002672ee2019e73 (diff) | |
Merge branch 'linux-linaro-2.6.38-master' into for-ubuntuu2
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) { |