]> git.itanic.dy.fi Git - linux-stable/commit
mm/mmap: undo ->mmap() when mas_preallocate() fails
authorMike Kravetz <mike.kravetz@oracle.com>
Tue, 18 Oct 2022 02:49:45 +0000 (19:49 -0700)
committerAndrew Morton <akpm@linux-foundation.org>
Fri, 21 Oct 2022 04:27:22 +0000 (21:27 -0700)
commit5789151e48acc3fd34d2109bf2021dc4df5e33e9
treee2d09b2ac8beca11692a13ef1c7a9e925efab146
parenteacf96d23f23e5bfd175be07048246efd0be4cc6
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 <mike.kravetz@oracle.com>
Reported-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Carlos Llamas <cmllamas@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mm/mmap.c