imapc: Don't trust mail stream to have correct CRLFs

It's not that expensive to just recalculate them. If they're not correct in
the stream, it can result in e.g. truncated emails due to wrong virtual_size
being used in body_size calculation. The wrong CRLFs can especially happen
if plugins modify the stream in istream_opened() hook.

diff --git a/src/lib-storage/index/imapc/imapc-mail-fetch.c b/src/lib-storage/index/imapc/imapc-mail-fetch.c
index b543a92a0e81ba301cbfa607857baeb6786fc596..42b32d2f39a6481d711da398b432e28e68be7738 100644 (file)
--- a/src/lib-storage/index/imapc/imapc-mail-fetch.c
+++ b/src/lib-storage/index/imapc/imapc-mail-fetch.c
@@ -589,12 +589,15 @@ void imapc_mail_init_stream(struct imapc_mail *mail)
           smaller than the fetched message header. In this case change the
           size as well, otherwise reading via istream-mail will fail. */
        if (mail->body_fetched || imail->data.physical_size < size) {
-               if (mail->body_fetched)
+               if (mail->body_fetched) {
                        imail->data.inexact_total_sizes = FALSE;
+                       /* Don't trust any existing virtual_size. Also don't
+                          set it to size, because there's no guarantees about
+                          the content having proper CRLF newlines, especially
+                          not if istream_opened() has changed the stream. */
+                       imail->data.virtual_size = (uoff_t)-1;
+               }
                imail->data.physical_size = size;
-               /* we'll assume that the remote server is working properly and
-                  sending CRLF linefeeds */
-               imail->data.virtual_size = size;
        }
 
        imail->data.stream_has_only_header = !mail->body_fetched;