File 0523-zlib-Fix-negative-Adler32-checksums.patch of Package erlang

From 5d7e400b7a37561a5f11564cac81505d456910ba Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?John=20H=C3=B6gberg?= <john@erlang.org>
Date: Mon, 16 Oct 2023 10:39:17 +0200
Subject: [PATCH] zlib: Fix negative Adler32 checksums

---
 erts/emulator/nifs/common/zlib_nif.c |  4 ++--
 lib/kernel/test/zlib_SUITE.erl       | 16 ++++++++++++++--
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/erts/emulator/nifs/common/zlib_nif.c b/erts/emulator/nifs/common/zlib_nif.c
index 2b8b691e11..92df1f48e1 100644
--- a/erts/emulator/nifs/common/zlib_nif.c
+++ b/erts/emulator/nifs/common/zlib_nif.c
@@ -472,7 +472,7 @@ static ERL_NIF_TERM zlib_codec(int (*codec)(z_stream*, int),
         }
 
         return enif_make_tuple3(env, am_need_dictionary,
-            enif_make_int(env, d->s.adler), flushed_output);
+            enif_make_ulong(env, d->s.adler), flushed_output);
     }
 }
 
@@ -669,7 +669,7 @@ static ERL_NIF_TERM zlib_deflateSetDictionary(ErlNifEnv *env, int argc, const ER
             checksum = adler32(0, bin.data, bin.size);
         }
 
-        return enif_make_int(env, checksum);
+        return enif_make_ulong(env, checksum);
     }
 
     return zlib_return(env, res);
diff --git a/lib/kernel/test/zlib_SUITE.erl b/lib/kernel/test/zlib_SUITE.erl
index 4c7af0d6ef..0b8af8c4c4 100644
--- a/lib/kernel/test/zlib_SUITE.erl
+++ b/lib/kernel/test/zlib_SUITE.erl
@@ -49,7 +49,7 @@
        chunk_bench_zeroed/1, chunk_bench_rand/1]).
 
 %% Others
--export([smp/1, otp_9981/1, otp_7359/1]).
+-export([smp/1, otp_9981/1, otp_7359/1, checksum/1]).
 
 -define(m(Guard, Expression),
     fun() ->
@@ -72,7 +72,8 @@ all() ->
     [{group, api}, {group, examples}, {group, func},
      {group, bench}, smp,
      otp_9981,
-     otp_7359].
+     otp_7359,
+     checksum].
 
 groups() -> 
     [{api, [],
@@ -1186,6 +1187,17 @@ otp_9981(Config) when is_list(Config) ->
     Ports = lists:sort(erlang:ports()),
     ok.
 
+%% ERIERL-994: the Adler32 checksum returned by the dictionary functionality
+%% could be negative due to returning a signed instead of unsigned integer.
+checksum(Config) when is_list(Config) ->
+    Z = zlib:open(),
+    ok = zlib:deflateInit(Z),
+    TestVec = list_to_binary(lists:duplicate(16, 255)),
+    Chk = zlib:deflateSetDictionary(Z, TestVec),
+    true = Chk >= 0,
+    zlib:close(Z),
+    ok.
+
 -define(BENCH_SIZE, (16 bsl 20)).
 
 -define(DECOMPRESS_BENCH(Name, What, Data),
-- 
2.35.3