tiny-printf: Avoid printing NULL strings

Add a check for NULL strings to avoid printing junk to the console.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stefan Roese <sr@denx.de>

diff --git a/lib/tiny-printf.c b/lib/tiny-printf.c
index 403b134..efe5c25 100644 (file)
--- a/lib/tiny-printf.c
+++ b/lib/tiny-printf.c
@@ -108,8 +108,10 @@ int vprintf(const char *fmt, va_list va)
                                w--;
                        while (w-- > 0)
                                putc(lz ? '0' : ' ');
-                       while ((ch = *p++))
-                               putc(ch);
+                       if (p) {
+                               while ((ch = *p++))
+                                       putc(ch);
+                       }
                }
        }