fdtgrep: Deal with NULL data passed to check_type_include()

Since the parameter can be NULL we must be careful not to dereference it
in this case.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reported-by: Coverity (CID: 163250)
Fixes: 1043d0a0 (fdt: Add fdtgrep tool)

diff --git a/tools/fdtgrep.c b/tools/fdtgrep.c
index e373c43e3699e3d4387072f4dd89dfa061284ce6..f51f5f15f5497e063158d81efa34c8bbd11eaa2a 100644 (file)
--- a/tools/fdtgrep.c
+++ b/tools/fdtgrep.c
@@ -522,18 +522,21 @@ static int check_type_include(void *priv, int type, const char *data, int size)
         * return 1 at the first match. For exclusive conditions, we must
         * check that there are no matches.
         */
-       for (val = disp->value_head; val; val = val->next) {
-               if (!(type & val->type))
-                       continue;
-               match = fdt_stringlist_contains(data, size, val->string);
-               debug("      - val->type=%x, str='%s', match=%d\n",
-                     val->type, val->string, match);
-               if (match && val->include) {
-                       debug("   - match inc %s\n", val->string);
-                       return 1;
+       if (data) {
+               for (val = disp->value_head; val; val = val->next) {
+                       if (!(type & val->type))
+                               continue;
+                       match = fdt_stringlist_contains(data, size,
+                                                       val->string);
+                       debug("      - val->type=%x, str='%s', match=%d\n",
+                             val->type, val->string, match);
+                       if (match && val->include) {
+                               debug("   - match inc %s\n", val->string);
+                               return 1;
+                       }
+                       if (match)
+                               none_match &= ~val->type;
                }
-               if (match)
-                       none_match &= ~val->type;
        }
 
        /*