mmap: call unlink_anon_vmas() in __split_vma() in case of error

If __split_vma fails because of an out of memory condition the
anon_vma_chain isn't teardown and freed potentially leading to rmap walks
accessing freed vma information plus there's a memleak.

Signed-off-by: Andrea Arcangeli <[email protected]>
Acked-by: Johannes Weiner <[email protected]>
Acked-by: Rik van Riel <[email protected]>
Acked-by: Hugh Dickins <[email protected]>
Cc: Marcelo Tosatti <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

diff --git a/mm/mmap.c b/mm/mmap.c
index 6128dc8e5ede709cada129438fbac101895aa09d..00161a48a45100c611ebaa053f0b1f1486d09f29 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2009,6 +2009,7 @@ static int __split_vma(struct mm_struct * mm, struct vm_area_struct * vma,
                        removed_exe_file_vma(mm);
                fput(new->vm_file);
        }
+       unlink_anon_vmas(new);
  out_free_mpol:
        mpol_put(pol);
  out_free_vma: