From: Aki Tuomi <aki.tuomi@open-xchange.com>
Date: Mon, 23 Feb 2026 12:09:02 +0000 (+0200)
Subject: [PATCH] lib-compression: istream-lz4 - Try again if no data was decompressed
X-Git-Tag: archive/raspbian/1%2.4.1+dfsg1-6+rpi1+deb13u7^2~90
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=c18662e96930febec97f4f64c323ce631822124a;p=dovecot.git

[PATCH] lib-compression: istream-lz4 - Try again if no data was decompressed


Gbp-Pq: Name 0001-lib-compression-istream-lz4-Try-again-if-no-data-was.patch
---

diff --git a/src/lib-compression/istream-lz4.c b/src/lib-compression/istream-lz4.c
index b59604c..ee2ddbb 100644
--- a/src/lib-compression/istream-lz4.c
+++ b/src/lib-compression/istream-lz4.c
@@ -198,7 +198,8 @@ static ssize_t i_stream_lz4_read(struct istream_private *stream)
 		lz4_read_error(zstream, "corrupted lz4 chunk");
 		stream->istream.stream_errno = EINVAL;
 		return -1;
-	}
+	} else if (ret == 0)
+		return i_stream_lz4_read(stream);
 	i_assert(ret > 0);
 	stream->pos += ret;
 	i_assert(stream->pos <= stream->buffer_size);
diff --git a/src/lib-compression/test-compression.c b/src/lib-compression/test-compression.c
index 1f9b6b9..7b3e339 100644
--- a/src/lib-compression/test-compression.c
+++ b/src/lib-compression/test-compression.c
@@ -1052,6 +1052,11 @@ static const unsigned char lz4_chunk_crash_02[] = {
 	 0x32, 0x01, 0xff, 0xff, 0x00, 0x30
 };
 
+static const unsigned char lz4_chunk_eof_03[] = {
+	0x44, 0x6f, 0x76, 0x65, 0x63, 0x6f, 0x74, 0x2d, 0x4c, 0x5a, 0x34, 0x0d,
+	0x2a, 0x9b, 0xc5, 0x00, 0x00, 0xff, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00,
+};
+
 static void test_lz4_chunk_size(void)
 {
 	const struct compression_handler *lz4;
@@ -1088,6 +1093,18 @@ static void test_lz4_chunk_size(void)
 
 	i_stream_unref(&input);
 
+	file_input = test_istream_create_data(lz4_chunk_eof_03,
+					      sizeof(lz4_chunk_eof_03));
+	input = lz4->create_istream(file_input);
+	i_stream_unref(&file_input);
+	i_stream_read(input);
+
+	/* no error, but no content either */
+	test_assert(input->eof);
+	test_assert(input->stream_errno == 0);
+
+	i_stream_unref(&input);
+
 	test_end();
 }