From: Timo Sirainen <timo.sirainen@open-xchange.com>
Date: Tue, 29 Oct 2024 09:25:32 +0000 (+0200)
Subject: lib: istream-concat - Fix potential hang when reaching max buffer size
X-Git-Tag: 2.4.0~1425
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=2adea4a410011cc8e290da180d5fc25006b0d3fe;p=thirdparty%2Fdovecot%2Fcore.git

lib: istream-concat - Fix potential hang when reaching max buffer size
---

diff --git a/src/lib/istream-concat.c b/src/lib/istream-concat.c
index 253edd6f60..a4860549ff 100644
--- a/src/lib/istream-concat.c
+++ b/src/lib/istream-concat.c
@@ -227,6 +227,13 @@ static ssize_t i_stream_concat_read(struct istream_private *stream)
 			return -2;
 		}
 		stream->buffer = stream->w_buffer;
+		if (size < new_bytes_count) {
+			/* Everything couldn't be added to the concat-istream's
+			   buffer. However, parent istream still contains data
+			   in its buffer and it might not be receiving more.
+			   Make sure the istream won't hang. */
+			i_stream_set_input_pending(&stream->istream, TRUE);
+		}
 
 		/* we'll copy all the new input to w_buffer. if we skip over
 		   prev_stream_left bytes, the next read will switch to