From 643e2dfa4ff8ea1fab0b6f1e1e06cdfbfc0a703a Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Mon, 9 May 2011 17:44:42 -0700 Subject: vm: fix vm_pgoff wrap in upward expansion commit 42c36f63ac1366ab0ecc2d5717821362c259f517 upstream. Commit a626ca6a6564 ("vm: fix vm_pgoff wrap in stack expansion") fixed the case of an expanding mapping causing vm_pgoff wrapping when you had downward stack expansion. But there was another case where IA64 and PA-RISC expand mappings: upward expansion. This fixes that case too. Signed-off-by: Hugh Dickins Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- mm/mmap.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/mm/mmap.c b/mm/mmap.c index 3e2f805c964..25a3783c25e 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1677,9 +1677,12 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address) size = address - vma->vm_start; grow = (address - vma->vm_end) >> PAGE_SHIFT; - error = acct_stack_growth(vma, size, grow); - if (!error) - vma->vm_end = address; + error = -ENOMEM; + if (vma->vm_pgoff + (size >> PAGE_SHIFT) >= vma->vm_pgoff) { + error = acct_stack_growth(vma, size, grow); + if (!error) + vma->vm_end = address; + } } anon_vma_unlock(vma); return error; -- cgit v1.2.3-18-g5258