Tidying: Issues detected by gcc --fsanitize=undefined

6 files changed, 17 insertions, 9 deletions

diff --git a/doc/doc-txt/ChangeLog b/doc/doc-txt/ChangeLog
index 7f8a62546..a3911ac18 100644
--- a/doc/doc-txt/ChangeLog
+++ b/doc/doc-txt/ChangeLog
@@ -175,6 +175,11 @@ JH/42 Bug 1796: Fix error logged on a malware scanner connection failure.
 
 HS/04 Add support for keep_environment and add_environment options.
 
+JH/43 Tidy coding issues detected by gcc --fsanitize=undefined.  Some remain;
+      either intentional arithmetic overflow during PRNG, or testing config-
+      induced overflows.
+
+
 
 Exim version 4.86
 -----------------
diff --git a/src/src/auths/sha1.c b/src/src/auths/sha1.c
index 67a11912e..a92bb71d1 100644
--- a/src/src/auths/sha1.c
+++ b/src/src/auths/sha1.c
@@ -62,15 +62,15 @@ Returns:     nothing
 void
 sha1_mid(sha1 *base, const uschar *text)
 {
-register int i;
-unsigned int A, B, C, D, E;
-unsigned int W[80];
+int i;
+uint A, B, C, D, E;
+uint W[80];
 
 base->length += 64;
 
 for (i = 0; i < 16; i++)
   {
-  W[i] = (text[0] << 24) | (text[1] << 16) | (text[2] << 8) | text[3];
+  W[i] = ((uint)text[0] << 24) | (text[1] << 16) | (text[2] << 8) | text[3];
   text += 4;
   }
 
diff --git a/src/src/expand.c b/src/src/expand.c
index 66172f378..b4cc79d4b 100644
--- a/src/src/expand.c
+++ b/src/src/expand.c
@@ -1073,6 +1073,8 @@ return s;
 
 Returns:  a pointer to the character after the last digit
 */
+/*XXX consider expanding to int_eximarith_t.  But the test for
+"overbig numbers" in 0002 still needs to overflow it. */
 
 static uschar *
 read_number(int *n, uschar *s)
diff --git a/src/src/host.c b/src/src/host.c
index 90ba852d8..6a6e7abf8 100644
--- a/src/src/host.c
+++ b/src/src/host.c
@@ -1067,7 +1067,7 @@ if (Ustrchr(address, ':') != NULL)
 /* Handle IPv4 address */
 
 (void)sscanf(CS address, "%d.%d.%d.%d", x, x+1, x+2, x+3);
-bin[v4offset] = (x[0] << 24) + (x[1] << 16) + (x[2] << 8) + x[3];
+bin[v4offset] = ((uint)x[0] << 24) + (x[1] << 16) + (x[2] << 8) + x[3];
 return v4offset+1;
 }
 
@@ -1098,7 +1098,7 @@ for (i = 0; i < count; i++)
   if (mask == 0) wordmask = 0;
   else if (mask < 32)
     {
-    wordmask = (-1) << (32 - mask);
+    wordmask = (uint)(-1) << (32 - mask);
     mask = 0;
     }
   else
@@ -1321,7 +1321,7 @@ for (i = 0; i < size; i++)
   if (mlen == 0) mask = 0;
   else if (mlen < 32)
     {
-    mask = (-1) << (32 - mlen);
+    mask = (uint)(-1) << (32 - mlen);
     mlen = 0;
     }
   else
diff --git a/src/src/readconf.c b/src/src/readconf.c
index ead74c1d0..3654f19d1 100644
--- a/src/src/readconf.c
+++ b/src/src/readconf.c
@@ -2039,6 +2039,7 @@ switch (type)
 
   /*  Integer held in K: again, allow octal and hex formats, and suffixes K and
   M. */
+  /*XXX consider moving to int_eximarith_t (but mind the overflow test 0415) */
 
   case opt_Kint:
     {
diff --git a/src/src/transports/autoreply.c b/src/src/transports/autoreply.c
index d2aad542a..e93267e48 100644
--- a/src/src/transports/autoreply.c
+++ b/src/src/transports/autoreply.c
@@ -267,7 +267,6 @@ autoreply_transport_entry(
 {
 int fd, pid, rc;
 int cache_fd = -1;
-int log_fd = -1;
 int cache_size = 0;
 int add_size = 0;
 EXIM_DB *dbm_file = NULL;
@@ -522,9 +521,10 @@ if (oncelog != NULL && *oncelog != 0 && to != NULL)
 
   if (then != 0 && (once_repeat_sec <= 0 || now - then < once_repeat_sec))
     {
+    int log_fd;
     DEBUG(D_transport) debug_printf("message previously sent to %s%s\n", to,
       (once_repeat_sec > 0)? " and repeat time not reached" : "");
-    log_fd = Uopen(logfile, O_WRONLY|O_APPEND|O_CREAT, ob->mode);
+    log_fd = logfile ? Uopen(logfile, O_WRONLY|O_APPEND|O_CREAT, ob->mode) : -1;
     if (log_fd >= 0)
       {
       uschar *ptr = log_buffer;