discover: check config.boot_device before setting a default

If a default device is set, we only allow booting from that device.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

1 files changed, 20 insertions, 0 deletions

diff --git a/discover/device-handler.c b/discover/device-handler.c
index 7f7081d..b93cdfa 100644
--- a/discover/device-handler.c
+++ b/discover/device-handler.c
@@ -441,6 +441,22 @@ static int default_option_priority(struct discover_boot_option *opt)
 	return 0;
 }
 
+static bool device_allows_default(struct discover_device *dev)
+{
+	const char *dev_str;
+
+	dev_str = config_get()->boot_device;
+
+	if (!dev_str || !strlen(dev_str))
+		return true;
+
+	/* default devices are specified by UUIDs at present */
+	if (strcmp(dev->uuid, dev_str))
+		return false;
+
+	return true;
+}
+
 static void set_default(struct device_handler *handler,
 		struct discover_boot_option *opt)
 {
@@ -449,6 +465,10 @@ static void set_default(struct device_handler *handler,
 	if (!handler->autoboot_enabled)
 		return;
 
+	/* do we allow default-booting from this device? */
+	if (!device_allows_default(opt->device))
+		return;
+
 	new_prio = default_option_priority(opt);
 
 	/* A negative priority indicates that we don't want to boot this device