From 5789151e48acc3fd34d2109bf2021dc4df5e33e9 Mon Sep 17 00:00:00 2001 From: Mike Kravetz Date: Mon, 17 Oct 2022 19:49:45 -0700 Subject: [PATCH] mm/mmap: undo ->mmap() when mas_preallocate() fails A memory leak in hugetlb_reserve_pages was reported in [1]. The root cause was traced to an error path in mmap_region when mas_preallocate() fails. In this case, the vma is freed after a successful call to filesystem specific mmap. The hugetlbfs mmap routine may allocate data structures pointed to by m_private_data. These need to be cleaned up by the hugetlb vm_ops->close() routine. The same issue was addressed by commit deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails") for the arch_validate_flags() test. Go to the same close_and_free_vma label if mas_preallocate() fails. [1] https://lore.kernel.org/linux-mm/CAKXUXMxf7OiCwbxib7MwfR4M1b5+b3cNTU7n5NV9Zm4967=FPQ@mail.gmail.com/ Link: https://lkml.kernel.org/r/20221018024945.415036-1-mike.kravetz@oracle.com Fixes: d4af56c5c7c6 ("mm: start tracking VMAs with maple tree") Signed-off-by: Mike Kravetz Reported-by: Lukas Bulwahn Reviewed-by: Liam R. Howlett Cc: Andrii Nakryiko Cc: Carlos Llamas Cc: Catalin Marinas Cc: Muchun Song Signed-off-by: Andrew Morton --- mm/mmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/mmap.c b/mm/mmap.c index bf2122a..3c9890e 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2681,7 +2681,7 @@ cannot_expand: if (mas_preallocate(&mas, vma, GFP_KERNEL)) { error = -ENOMEM; if (file) - goto unmap_and_free_vma; + goto close_and_free_vma; else goto free_vma; } -- 2.7.4