Merge remote-tracking branch 'tor-github/pr/848' into maint-0.4.0

diff --cc src/feature/dircommon/consdiff.c
index 698f548013b49db82b964f05e0c7124ee1b7eabb,1b90dfe99e6913dcfd43181007df55b83dc7efb8..8e93953f73d3baedb2b93690014493475e911387
--- 1/src/feature/dircommon/consdiff.c
--- 2/src/or/consdiff.c
+++ b/src/feature/dircommon/consdiff.c
@@@ -1387,9 -1383,9 +1387,9 @@@ consensus_diff_apply(const char *consen
    char *result = NULL;
    memarea_t *area = memarea_new();
  
 -  r1 = consensus_compute_digest_as_signed(consensus, &d1);
 +  r1 = consensus_compute_digest_as_signed(consensus, consensus_len, &d1);
    if (BUG(r1 < 0))
-     return NULL; // LCOV_EXCL_LINE
+     goto done;
  
    lines1 = smartlist_new();
    lines2 = smartlist_new();