Add advisory for double-free issues in id-map

crates/id-map/RUSTSEC-0000-0000.md

@@ -0,0 +1,34 @@
+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "id-map"
+date = "2021-02-26"
+url = "https://github.com/andrewhickman/id-map/issues/3"
+categories = ["memory-corruption"]
+keywords = ["memory-safety", "double-free"]
+
+[versions]
+patched = []
+```
+
+# Multiple functions can cause double-frees
+
+The following functions in the crate are affected:
+
+## `IdMap::clone_from`
+
+The `clone_from` implementation for `IdMap` drops the values present in the
+map and then begins cloning values from the other map. If a `.clone()` call
+pancics, then the afformentioned dropped elements can be freed again.
+
+## `get_or_insert`
+
+`get_or_insert` reserves space for a value, before calling the user provided
+insertion function `f`. If the function `f` panics then uninitialized or
+previously freed memory can be dropped.
+
+## `remove_set`
+
+When removing a set of elements, `ptr::drop_in_place` is called on each of the
+element to be removed. If the `Drop` impl of one of these elements panics then
+the previously dropped elements can be dropped again.