diff --git a/ChangeLog.adoc b/ChangeLog.adoc
index a68c4ec83..834bdd05e 100644
--- a/ChangeLog.adoc
+++ b/ChangeLog.adoc
@@ -15,6 +15,7 @@ For a list of important changes that require manual actions, please look at rele
 
 Bug fixes::
 
+  * core: fix integer overflow when setting integer option with `++N` or `--N`
   * irc: add missing tags on multiline messages (issue #1987)
   * irc: fix redirection of command `/list` when the reply doesn't start with message 321 (start of /list)
 
diff --git a/src/core/wee-config-file.c b/src/core/wee-config-file.c
index fc2123ffa..648aafa93 100644
--- a/src/core/wee-config-file.c
+++ b/src/core/wee-config-file.c
@@ -1527,22 +1527,22 @@ config_file_option_set (struct t_config_option *option, const char *value,
                         {
                             error = NULL;
                             number = strtol (value + 2, &error, 10);
-                            if (error && !error[0])
+                            if (error && !error[0]
+                                && (long)old_value + number <= (long)(option->max))
                             {
                                 value_int = old_value + number;
-                                if (value_int <= option->max)
-                                    new_value_ok = 1;
+                                new_value_ok = 1;
                             }
                         }
                         else if (strncmp (value, "--", 2) == 0)
                         {
                             error = NULL;
                             number = strtol (value + 2, &error, 10);
-                            if (error && !error[0])
+                            if (error && !error[0]
+                                && (long)old_value - number >= (long)(option->min))
                             {
                                 value_int = old_value - number;
-                                if (value_int >= option->min)
-                                    new_value_ok = 1;
+                                new_value_ok = 1;
                             }
                         }
                         else