because the IN_RENAME flag only fixes a few of the huge number of race
conditions that can result in the source path becoming invalid even
prior to the VOP_RENAME() call. The panics created a serious security
issue whereby an attacker could fairly easily cause the panic to
occur, crashing the machine.
The correct solution requires a great deal of work in the namei
path cache code.
MFC after: 0 days
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