bug report

diff --git a/doc/bugs/worktree_overwrite_races.mdwn b/doc/bugs/worktree_overwrite_races.mdwn
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+Similar to [[add_overwrite_race]], several callers of replaceWorkTreeFile
+are susceptable to a race. They do some check of the current content of the
+file, and then they call that to replace it with something else. But in
+between, the file could be overwritten with other content. And that content
+then gets replaced, which is not expected behavior.
+
+Some other commands may modify the worktree without using it (oops)
+and also be susceptable to a race. `git-annex fix` in fixSymlink, for example,
+checks if the file is a symlink, and then deletes and recreates it.
+
+[[!commit 5ef79125ad0eddd5467b6bec451fdcdbd748b96f]] fixed one of these
+races, but not in an ideal way.
+
+Better would probably be for replaceWorkTreeFile to be provided with a
+InodeCache of the content of the worktree file that is ok to replace.
+Then it can move the file to a temp directory, check that it's still
+unmodified, and replace it. --[[Joey]]