fix: prevent data races in MemFs Rename and RemoveAll #3
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mafredri
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mafredri
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Dec 12, 2025
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| m.registerWithParent(file, 0) | ||
| m.mu.Unlock() | ||
| m.getData()[name] = file |
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Review: Drive-by change in preparation of potential future removal of implicit MkdirAll behavior of registerWithParent.
The ordering is more explicit and avoids inconsistent state if an error path is introduced.
Rename: If unRegisterWithParent or renameDescendants returns an error, the function returns while holding an exclusive write lock, but the deferred RUnlock runs instead of Unlock. RemoveAll: Unsafe modification of data map under the assumption that all entries belong to unregistered path. This implementaiton also raced with non-standard implicit MkdirAll behavior of Create.
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| m.registerWithParent(item, perm) | ||
| m.mu.Unlock() | ||
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| return m.setFileMode(name, perm|os.ModeDir) |
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Review: Dupe, mem.SetMode is already used above.
mafredri
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Dec 12, 2025
| m.mu.Lock() | ||
| mem.SetModTime(f, mtime) | ||
| m.mu.Unlock() | ||
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Motivation: Consistency. We already have a reference to the file handle, and mem functions acquire f.Lock. Whether or not we're updating a stale file is irrelevant.
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Rename: If unRegisterWithParent or renameDescendants returns an error,
the function returns while holding an exclusive write lock, but the
deferred RUnlock runs instead of Unlock.
RemoveAll: Unsafe modification of data map under the assumption that all
entries belong to unregistered path. This implementaiton also raced with
non-standard implicit MkdirAll behavior of Create.