auth: db-passwd-file - Fix using paths with %% escaped characters but no %variables

full_key might not have been NULL, causing var_expand() to read past the
array and possibly crash.

diff --git a/src/auth/db-passwd-file.c b/src/auth/db-passwd-file.c
index 6a5113cd44ff2c10a69d93120d9bbbb7ba5b63cd..e26c1466d66b1ef4bdb770bca05dd8cbe8d7f29d 100644 (file)
--- a/src/auth/db-passwd-file.c
+++ b/src/auth/db-passwd-file.c
@@ -350,11 +350,12 @@ db_passwd_file_init(const char *path, bool userdb, bool debug)
 
        if (percents && !db->vars) {
                /* just extra escaped % chars. remove them. */
-               struct var_expand_table empty_table[1];
+               struct var_expand_table empty_table[1] = {
+                       { .key = '\0' },
+               };
                string_t *dest;
                const char *error;
 
-               empty_table[0].key = '\0';
                dest = t_str_new(256);
                if (var_expand(dest, path, empty_table, &error) <= 0)
                        i_unreached();