mmap: fix error paths with dup_anon_vma()

When the calling function fails after the dup_anon_vma(), the
duplication of the anon_vma is not being undone.  Add the necessary
unlink_anon_vma() call to the error paths that are missing them.

This issue showed up during inspection of the error path in vma_merge()
for an unrelated vma iterator issue.

Users may experience increased memory usage, which may be problematic as
the failure would likely be caused by a low memory situation.

Link: https://lkml.kernel.org/r/[email protected]
Fixes: d4af56c5c7c6 ("mm: start tracking VMAs with maple tree")
Signed-off-by: Liam R. Howlett <[email protected]>
Reviewed-by: Lorenzo Stoakes <[email protected]>
Acked-by: Vlastimil Babka <[email protected]>
Cc: Jann Horn <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Suren Baghdasaryan <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions