Sean Christopherson d6aba4c8e2 hugetlbfs: fix off-by-one error in hugetlb_vmdelete_list() ... Pass "end - 1" instead of "end" when walking the interval tree in hugetlb_vmdelete_list() to fix an inclusive vs. exclusive bug. The two callers that pass a non-zero "end" treat it as exclusive, whereas the interval tree iterator expects an inclusive "last". E.g. punching a hole in a file that precisely matches the size of a single hugepage, with a vma starting right on the boundary, will result in unmap_hugepage_range() being called twice, with the second call having start==end. The off-by-one error doesn't cause functional problems as __unmap_hugepage_range() turns into a massive nop due to short-circuiting its for-loop on "address < end". But, the mmu_notifier invocations to invalid_range_{start,end}() are passed a bogus zero-sized range, which may be unexpected behavior for secondary MMUs. The bug was exposed by commit ed922739c9 ("KVM: Use interval tree to do fast hva lookup in memslots"), currently queued in the KVM tree for 5.17, which added a WARN to detect ranges with start==end. Link: https://lkml.kernel.org/r/20211228234257.1926057-1-seanjc@google.com Fixes: 1bfad99ab4 ("hugetlbfs: hugetlb_vmtruncate_list() needs to take a range to delete") Signed-off-by: Sean Christopherson <seanjc@google.com> Reported-by: syzbot+4e697fe80a31aa7efe21@syzkaller.appspotmail.com Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2022-01-15 16:30:30 +02:00
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inode.c	hugetlbfs: fix off-by-one error in hugetlb_vmdelete_list()	2022-01-15 16:30:30 +02:00
Makefile	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00