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| author | Mark Brown <broonie@opensource.wolfsonmicro.com> | 2011-04-18 17:12:14 +0100 |
|---|---|---|
| committer | Mark Brown <broonie@opensource.wolfsonmicro.com> | 2011-04-18 17:12:14 +0100 |
| commit | fac56c2df51bc29b07b3c2dcfabf32a015a0522c (patch) | |
| tree | 1ff5d84ecf4ea0bcbd42e2ef9624b5ade3810890 /mm/mremap.c | |
| parent | 6caa15d0b84d2ea688fd31f4f172c8353463e109 (diff) | |
| parent | a6360dd37e1a144ed11e6548371bade559a1e4df (diff) | |
Merge commit 'v2.6.39-rc3' into for-2.6.39
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 1de98d492ddc..a7c1f9f9b941 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) { |