Fix validation of missing percentage arguments.

diff --git a/usr.bin/tmux/arguments.c b/usr.bin/tmux/arguments.c
index 5bac7fa..4e6515e 100644 (file)
--- a/usr.bin/tmux/arguments.c
+++ b/usr.bin/tmux/arguments.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: arguments.c,v 1.55 2022/06/07 10:02:19 nicm Exp $ */
+/* $OpenBSD: arguments.c,v 1.56 2022/08/02 09:23:34 nicm Exp $ */
 
 /*
  * Copyright (c) 2010 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -895,6 +895,10 @@ args_percentage(struct args *args, u_char flag, long long minval,
                *cause = xstrdup("missing");
                return (0);
        }
+       if (TAILQ_EMPTY(&entry->values)) {
+               *cause = xstrdup("empty");
+               return (0);
+       }
        value = TAILQ_LAST(&entry->values, args_values)->string;
        return (args_string_percentage(value, minval, maxval, curval, cause));
 }
@@ -909,6 +913,10 @@ args_string_percentage(const char *value, long long minval, long long maxval,
        size_t           valuelen = strlen(value);
        char            *copy;
 
+       if (valuelen == 0) {
+               *cause = xstrdup("empty");
+               return (0);
+       }
        if (value[valuelen - 1] == '%') {
                copy = xstrdup(value);
                copy[valuelen - 1] = '\0';
@@ -955,6 +963,10 @@ args_percentage_and_expand(struct args *args, u_char flag, long long minval,
                *cause = xstrdup("missing");
                return (0);
        }
+       if (TAILQ_EMPTY(&entry->values)) {
+               *cause = xstrdup("empty");
+               return (0);
+       }
        value = TAILQ_LAST(&entry->values, args_values)->string;
        return (args_string_percentage_and_expand(value, minval, maxval, curval,
                    item, cause));