erts: Fix memory leak of enif_inspect_* on independent environment

Affects enif_inspect_iolist_as_binary() on iolists
and enif_inspect_binary() on byte-unaligned binaries.

Also need to allocate inspection buffers in ERTS_ALC_T_NIF for
process independent environments, as we don't know when and where
the environment will be freed.

2 files changed, 43 insertions, 3 deletions

diff --git a/erts/emulator/test/nif_SUITE.erl b/erts/emulator/test/nif_SUITE.erl
index 5c82a01bd1..370363bf9e 100644
--- a/erts/emulator/test/nif_SUITE.erl
+++ b/erts/emulator/test/nif_SUITE.erl
@@ -35,7 +35,9 @@
 	 resource_takeover/1,
 	 threading/1, send/1, send2/1, send3/1, send_threaded/1, neg/1, 
 	 is_checks/1,
-	 get_length/1, make_atom/1, make_string/1, reverse_list_test/1]).
+	 get_length/1, make_atom/1, make_string/1, reverse_list_test/1,
+	 otp_9668/1
+	]).
 
 -export([many_args_100/100]).
 
@@ -60,7 +62,9 @@ all() ->
      iolist_as_binary, resource, resource_binary,
      resource_takeover, threading, send, send2, send3,
      send_threaded, neg, is_checks, get_length, make_atom,
-     make_string,reverse_list_test].
+     make_string,reverse_list_test,
+     otp_9668
+    ].
 
 groups() -> 
     [].
@@ -1236,6 +1240,20 @@ reverse_list_test(Config) ->
     ?line RevList = reverse_list(List),
     ?line badarg = reverse_list(foo).
 
+otp_9668(doc) -> ["Memory leak of tmp-buffer when inspecting iolist or unaligned binary in unbound environment"];
+otp_9668(Config) ->
+    ensure_lib_loaded(Config, 1),
+    TmpMem = tmpmem(),
+    IOList = ["This",' ',<<"is">>,' ',[<<"an iolist">>,'.']],    
+    otp_9668_nif(IOList),
+
+    <<_:5/bitstring,UnalignedBin:10/binary,_/bitstring>> = <<"Abuse me as unaligned">>,
+    otp_9668_nif(UnalignedBin),
+
+    ?line verify_tmpmem(TmpMem),
+    ok.
+
+
 tmpmem() ->
     case erlang:system_info({allocator,temp_alloc}) of
 	false -> undefined;
@@ -1345,6 +1363,7 @@ send_term(_,_) -> ?nif_stub.
 reverse_list(_) -> ?nif_stub.
 echo_int(_) -> ?nif_stub.
 type_sizes() -> ?nif_stub.
+otp_9668_nif(_) -> ?nif_stub.
 
 nif_stub_error(Line) ->
     exit({nif_not_loaded,module,?MODULE,line,Line}).
diff --git a/erts/emulator/test/nif_SUITE_data/nif_SUITE.c b/erts/emulator/test/nif_SUITE_data/nif_SUITE.c
index 35f54d62c5..7d7903af25 100644
--- a/erts/emulator/test/nif_SUITE_data/nif_SUITE.c
+++ b/erts/emulator/test/nif_SUITE_data/nif_SUITE.c
@@ -1431,6 +1431,26 @@ static ERL_NIF_TERM reverse_list(ErlNifEnv* env, int argc, const ERL_NIF_TERM ar
     return rev_list;
 }
 
+static ERL_NIF_TERM otp_9668_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
+{
+    /* Inspect in process independent env */
+    ErlNifEnv* myenv = enif_alloc_env();
+    ERL_NIF_TERM mycopy = enif_make_copy(myenv, argv[0]);
+    ErlNifBinary obin, cbin;
+
+    if ((enif_inspect_binary(env, argv[0], &obin)
+	 && enif_inspect_binary(myenv, mycopy, &cbin))
+	||
+	(enif_inspect_iolist_as_binary(env, argv[0], &obin)
+	 && enif_inspect_iolist_as_binary(myenv, mycopy, &cbin)))
+    {
+	assert(obin.size == cbin.size);
+	assert(memcmp(obin.data, cbin.data, obin.size) == 0);
+    }	
+    enif_free_env(myenv);
+    return atom_ok;
+}
+
 static ErlNifFunc nif_funcs[] =
 {
     {"lib_version", 0, lib_version},
@@ -1478,7 +1498,8 @@ static ErlNifFunc nif_funcs[] =
     {"send_term", 2, send_term},
     {"reverse_list",1, reverse_list},
     {"echo_int", 1, echo_int},
-    {"type_sizes", 0, type_sizes}
+    {"type_sizes", 0, type_sizes},
+    {"otp_9668_nif", 1, otp_9668_nif}
 };
 
 ERL_NIF_INIT(nif_SUITE,nif_funcs,load,reload,upgrade,unload)