debian/patches/90_Cutthrough-Fix-bug-with-dot-only-line.patch

   1 From 2d51a06458d4fb771dca34966cf2d19c6820ce61 Mon Sep 17 00:00:00 2001
   2 From: Jeremy Harris <jgh146exb@wizmail.org>
   3 Date: Thu, 21 Jan 2016 15:37:08 +0000
   4 Subject: [PATCH] Cutthrough: Fix bug with dot-only line
   5  JH/38 Fix cutthrough bug with body lines having a single dot. The dot was
   6       incorrectly not doubled on cutthrough transmission, hence seen as a
   7       body-termination at the receiving system - resulting in truncated mails.
   8       Commonly the sender saw a TCP-level error, and retransmitted the nessage
   9       via the normal store-and-forward channel. This could result in duplicates
  10       received - but deduplicating mailstores were liable to retain only the
  11       initial truncated version.
  12  (cherry picked from commit 1bc460a64a0de0766d21f4f8660c6597bc410cbc)
  13
  14 --- exim4-4.84.2.orig/src/receive.c
  15 +++ exim4-4.84.2/src/receive.c
  16 @@ -838,7 +838,15 @@ while ((ch = (receive_getc)()) != EOF)
  17        ch_state = 4;
  18        continue;
  19        }
  20 -    ch_state = 1;                       /* The dot itself is removed */
  21 +    /* The dot was removed at state 3. For a doubled dot, here, reinstate
  22 +    it to cutthrough. The current ch, dot or not, is passed both to cutthrough
  23 +    and to file below. */
  24 +    if (ch == '.')
  25 +      {
  26 +      uschar c= ch;
  27 +      (void) cutthrough_puts(&c, 1);
  28 +      }
  29 +    ch_state = 1;
  30      break;
  31
  32      case 4:                             /* After [CR] LF . CR */