In the Linux kernel, the following vulnerability has been resolved: ntfs: take invalidate_lock in ntfs_setattr_size() ntfs_setattr_size() updates i_size and resizes the on-disk attribute without holding mapping->invalidate_lock. Page faults take the lock shared, so a fault racing the resize can resolve a VCN against the transient runlist state of ntfs_non_resident_attr_expand() and fail with a spurious SIGBUS, and can interleave with the size-change epilogue (truncate_pagecache(), i_size_write(), pagecache_isize_extended()). Take invalidate_lock exclusively around the whole resize after inode_dio_wait(), matching the fallocate path and other filesystems such as xfs, which wraps truncate in its mmaplock (= invalidate_lock).
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