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File 0926-erts-Fix-memory-leak-of-fragmented-message-to-unalia.patch of Package erlang (Revision 3624bc22143be68439892ea1c7edb9a8)

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From d154a389cada12bed67e35c4875965d6a8933d2c Mon Sep 17 00:00:00 2001
From: Rickard Green <rickard@erlang.org>
Date: Wed, 29 Nov 2023 22:54:14 +0100
Subject: [PATCH] [erts] Fix memory leak of fragmented message to unaliased
 process

---
 erts/emulator/beam/dist.c               |  3 +-
 erts/emulator/beam/erl_proc_sig_queue.c |  8 ++-
 erts/emulator/test/process_SUITE.erl    | 84 ++++++++++++++++++++++++-
 3 files changed, 91 insertions(+), 4 deletions(-)

diff --git a/erts/emulator/beam/dist.c b/erts/emulator/beam/dist.c
index 0967b94809..4ed7ce2460 100644
--- a/erts/emulator/beam/dist.c
+++ b/erts/emulator/beam/dist.c
@@ -2452,11 +2452,12 @@ int erts_net_message(Port *prt,
             if (!is_external_pid(watcher))
                 goto invalid_message;
             if (erts_this_dist_entry == external_pid_dist_entry(watcher))
-                break;
+                goto monitored_process_not_alive;
             goto invalid_message;
         }
 
         if (!erts_proc_lookup(watcher)) {
+        monitored_process_not_alive:
             if (ede_hfrag != NULL) {
                 erts_free_dist_ext_copy(erts_get_dist_ext(ede_hfrag));
                 free_message_buffer(ede_hfrag);
diff --git a/erts/emulator/beam/erl_proc_sig_queue.c b/erts/emulator/beam/erl_proc_sig_queue.c
index 83b6991809..dbc0be63de 100644
--- a/erts/emulator/beam/erl_proc_sig_queue.c
+++ b/erts/emulator/beam/erl_proc_sig_queue.c
@@ -1565,8 +1565,14 @@ erts_proc_sig_send_dist_to_alias(Eterm alias, ErtsDistExternal *edep,
 
     ASSERT(is_ref(alias));
     pid = erts_get_pid_of_ref(alias);
-    if (!is_internal_pid(pid))
+    if (!is_internal_pid(pid)) {
+        if (hfrag) {
+            /* Fragmented message... */
+            erts_free_dist_ext_copy(erts_get_dist_ext(hfrag));
+            free_message_buffer(hfrag);
+        }
         return;
+    }
 
     /*
      * The receiver can distinguish between these two scenarios by
diff --git a/erts/emulator/test/process_SUITE.erl b/erts/emulator/test/process_SUITE.erl
index f5abc2cdbd..a977f75378 100644
--- a/erts/emulator/test/process_SUITE.erl
+++ b/erts/emulator/test/process_SUITE.erl
@@ -79,6 +79,8 @@
          spawn_request_reply_option/1,
          dist_spawn_arg_list_mixup/1,
          alias_bif/1,
+         dist_frag_alias/1,
+         dist_frag_unaliased/1,
          monitor_alias/1,
          spawn_monitor_alias/1,
          alias_process_exit/1,
@@ -149,7 +151,8 @@ groups() ->
        otp_16436, otp_16642]},
      {alias, [],
       [alias_bif, monitor_alias, spawn_monitor_alias, alias_process_exit,
-       demonitor_aliasmonitor, down_aliasmonitor]}].
+       demonitor_aliasmonitor, down_aliasmonitor,
+       dist_frag_alias, dist_frag_unaliased]}].
 
 init_per_suite(Config) ->
     A0 = case application:start(sasl) of
@@ -4078,7 +4081,84 @@ alias_bif_test(Node) ->
                               end),
     [{A3,1},{'DOWN', M3, _, _, _}] = recv_msgs(2),
     ok.
-             
+
+dist_frag_alias(Config) when is_list(Config) ->
+    Tester = self(),
+    {ok, Node} = start_node(Config),
+    {P,M} = spawn_monitor(Node,
+                          fun () ->
+                                  Alias = alias(),
+                                  Tester ! {alias, Alias},
+                                  receive
+                                      {data, Data} ->
+                                          garbage_collect(),
+                                          Tester ! {received_data, Data}
+                                  end,
+                                  exit(end_of_test)
+                          end),
+    Data = term_to_binary(lists:seq(1, 1000000)),
+    receive
+        {alias, Alias} ->
+            Alias ! {data, Data},
+            receive
+                {received_data, RecvData} ->
+                    Data = RecvData;
+                {'DOWN', M, process, P, R2} ->
+                    ct:fail(R2)
+            end;
+        {'DOWN', M, process, P, R1} ->
+            ct:fail(R1)
+    end,
+    receive
+        {'DOWN', M, process, P, R3} ->
+            end_of_test = R3
+    end,
+    stop_node(Node),
+    ok.
+
+dist_frag_unaliased(Config) when is_list(Config) ->
+    %% Leak fixed by PR-7915 would have been detected using asan or valgrind
+    %% when running this test...
+    Tester = self(),
+    {ok, Node} = start_node(Config),
+    {P,M} = spawn_monitor(Node,
+                          fun () ->
+                                  Alias = alias(),
+                                  Tester ! {alias, Alias},
+                                  receive
+                                      {data, Data} ->
+                                          garbage_collect(),
+                                          unalias(Alias),
+                                          Tester ! {received_data, Data},
+                                          receive
+                                              {data, _Data} ->
+                                                  exit(received_data_again);
+                                              end_of_test ->
+                                                  exit(end_of_test)
+                                          end
+                                  end
+                          end),
+    Data = term_to_binary(lists:seq(1, 1000000)),
+    receive
+        {alias, Alias} ->
+            Alias ! {data, Data},
+            receive
+                {received_data, RecvData} ->
+                    Data = RecvData;
+                {'DOWN', M, process, P, R2} ->
+                    ct:fail(R2)
+            end,
+            Alias ! {data, Data},
+            P ! end_of_test;
+        {'DOWN', M, process, P, R1} ->
+            ct:fail(R1)
+    end,
+    receive
+        {'DOWN', M, process, P, R3} ->
+            end_of_test = R3
+    end,
+    stop_node(Node),
+    ok.
 
 monitor_alias(Config) when is_list(Config) ->
     PRTSz = pid_ref_table_size(),
-- 
2.35.3

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File 0926-erts-Fix-memory-leak-of-fragmented-message-to-unalia.patch of Package erlang (Revision 3624bc22143be68439892ea1c7edb9a8)

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