cmd_pxe.c: Pass along 'cmdtp' to do_bootm()/do_bootz()

When we call do_bootm() with a vmlinuz, this would lead to a NULL
pointer dereference, and after talking with Wolfgang the right thing to
do here for now is to make sure that we pass cmdtp to these functions
rather than NULL.
Reported-by: NSteven A. Falco <stevenfalco@gmail.com>
Signed-off-by: NTom Rini <trini@ti.com>

common/cmd_pxe.c

@@ -572,7 +572,7 @@ static int label_localboot(struct pxe_label *label)
  * If the label specifies an 'append' line, its contents will overwrite that
  * of the 'bootargs' environment variable.
  */
-static int label_boot(struct pxe_label *label)
+static int label_boot(cmd_tbl_t *cmdtp, struct pxe_label *label)
 {
 	char *bootm_argv[] = { "bootm", NULL, NULL, NULL, NULL };
 	char initrd_str[22];
@@ -684,11 +684,11 @@ static int label_boot(struct pxe_label *label)
 	if (bootm_argv[3])
 		bootm_argc = 4;
 
-	do_bootm(NULL, 0, bootm_argc, bootm_argv);
+	do_bootm(cmdtp, 0, bootm_argc, bootm_argv);
 
 #ifdef CONFIG_CMD_BOOTZ
 	/* Try booting a zImage if do_bootm returns */
-	do_bootz(NULL, 0, bootm_argc, bootm_argv);
+	do_bootz(cmdtp, 0, bootm_argc, bootm_argv);
 #endif
 	return 1;
 }
@@ -1355,7 +1355,7 @@ static struct menu *pxe_menu_to_menu(struct pxe_menu *cfg)
 /*
  * Try to boot any labels we have yet to attempt to boot.
  */
-static void boot_unattempted_labels(struct pxe_menu *cfg)
+static void boot_unattempted_labels(cmd_tbl_t *cmdtp, struct pxe_menu *cfg)
 {
 	struct list_head *pos;
 	struct pxe_label *label;
@@ -1364,7 +1364,7 @@ static void boot_unattempted_labels(struct pxe_menu *cfg)
 		label = list_entry(pos, struct pxe_label, list);
 
 		if (!label->attempted)
-			label_boot(label);
+			label_boot(cmdtp, label);
 	}
 }
 
@@ -1380,7 +1380,7 @@ static void boot_unattempted_labels(struct pxe_menu *cfg)
  * If this function returns, there weren't any labels that successfully
  * booted, or the user interrupted the menu selection via ctrl+c.
  */
-static void handle_pxe_menu(struct pxe_menu *cfg)
+static void handle_pxe_menu(cmd_tbl_t *cmdtp, struct pxe_menu *cfg)
 {
 	void *choice;
 	struct menu *m;
@@ -1406,14 +1406,14 @@ static void handle_pxe_menu(struct pxe_menu *cfg)
 	 */
 
 	if (err == 1) {
-		err = label_boot(choice);
+		err = label_boot(cmdtp, choice);
 		if (!err)
 			return;
 	} else if (err != -ENOENT) {
 		return;
 	}
 
-	boot_unattempted_labels(cfg);
+	boot_unattempted_labels(cmdtp, cfg);
 }
 
 /*
@@ -1453,7 +1453,7 @@ do_pxe_boot(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 		return 1;
 	}
 
-	handle_pxe_menu(cfg);
+	handle_pxe_menu(cmdtp, cfg);
 
 	destroy_pxe_menu(cfg);
 
@@ -1559,7 +1559,7 @@ int do_sysboot(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	if (prompt)
 		cfg->prompt = 1;
 
-	handle_pxe_menu(cfg);
+	handle_pxe_menu(cmdtp, cfg);
 
 	destroy_pxe_menu(cfg);