From: Aki Tuomi <aki.tuomi@dovecot.fi>
Date: Mon, 12 Mar 2018 12:48:41 +0000 (+0200)
Subject: lib-dcrypt: istream-decrypt - Read more if buffer is empty
X-Git-Tag: 2.3.9~2147
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8c8d530a17e4b37e5fc9a5dfdd532bbb9811f895;p=thirdparty%2Fdovecot%2Fcore.git

lib-dcrypt: istream-decrypt - Read more if buffer is empty

If there is no more buffered data, try to decrypt more.

- Fixes Panic: file istream.c: line 192 (i_stream_read): assertion failed: (!stream->blocking)
- Fixes infinite loop when stream is not blocking
---

diff --git a/src/lib-dcrypt/istream-decrypt.c b/src/lib-dcrypt/istream-decrypt.c
index d9f27e0d55..4b0854dcb0 100644
--- a/src/lib-dcrypt/istream-decrypt.c
+++ b/src/lib-dcrypt/istream-decrypt.c
@@ -673,7 +673,8 @@ i_stream_decrypt_read(struct istream_private *stream)
 
 			bytes = new_pos - stream->pos;
 			stream->pos = new_pos;
-			return (ssize_t)bytes;
+			if (bytes > 0)
+				return (ssize_t)bytes;
 		}
 		if (dstream->finalized) {
 			/* all data decrypted */