svn commit: r292888 - head/sys/boot/uboot/common

[Ian Lepore]

Author: ian
Date: Tue Dec 29 21:29:05 2015
New Revision: 292888
URL: https://svnweb.freebsd.org/changeset/base/292888

Log:
  Fix the error checking for the ubenv command.  This moves the check for an
  empty ldvar (which amounts to the varname string starting with '=') into
  the if block that manipulates ldvar, which avoids later referencing ldvar
  when it was never initialized.
  
  Submitted by:	Thomas Skibo
  Pointy hat:	ian

Modified:
  head/sys/boot/uboot/common/main.c

Modified: head/sys/boot/uboot/common/main.c
==============================================================================
--- head/sys/boot/uboot/common/main.c	Tue Dec 29 20:51:29 2015	(r292887)
+++ head/sys/boot/uboot/common/main.c	Tue Dec 29 21:29:05 2015	(r292888)
@@ -585,6 +585,10 @@ handle_uboot_env_var(enum ubenv_action a
 	 */
 	if (action == UBENV_IMPORT) { 
 		len = strcspn(var, "=");
+		if (len == 0) {
+			printf("name cannot start with '=': '%s'\n", var);
+			return;
+		}
 		if (var[len] == 0) {
 			strcpy(ldvar, "uboot.");
 			strncat(ldvar, var, sizeof(ldvar) - 7);
@@ -604,9 +608,11 @@ handle_uboot_env_var(enum ubenv_action a
 		var = &var[6];
 	}
 
-	/* If ldvar is malformed or there's no variable name left, punt. */
-	if (ldvar[0] == 0 || var[0] == 0)
+	/* If there is no variable name left, punt. */
+	if (var[0] == 0) {
+		printf("empty variable name\n");
 		return;
+	}
 
 	val = ub_env_get(var);
 	if (action == UBENV_SHOW) {