discover/event: Fix incorrect calculation of param data length

[petitboot] / discover / event.c

diff --git a/discover/event.c b/discover/event.c
index cced6588d8b88aed85683668c93a9a19ddcc0178..0ccd3910e18396e989fe58ce8e8e423be6716373 100644 (file)
--- a/discover/event.c
+++ b/discover/event.c
@@ -22,10 +22,17 @@
 static int event_parse_ad_header(char *buf, int len, enum event_action *action,
        char **device)
 {
+       int headerlen;
        char *sep;
 
        *action = 0;
        *device = NULL;
+       headerlen = strnlen(buf, len);
+
+       if (!headerlen) {
+               pb_log("%s: bad header, no data\n", __func__);
+               return -1;
+       }
 
        /* we should see an <action>@<device>\0 at the head of the buffer */
        sep = strchr(buf, '@');
@@ -36,7 +43,6 @@ static int event_parse_ad_header(char *buf, int len, enum event_action *action,
 
        /* terminate the action string */
        *sep = '\0';
-       len -= sep - buf + 1;
 
        if (streq(buf, "add"))
                *action = EVENT_ACTION_ADD;
@@ -55,7 +61,7 @@ static int event_parse_ad_header(char *buf, int len, enum event_action *action,
        }
 
        *device = sep + 1;
-       return 0;
+       return headerlen;
 }
 
 /**
@@ -102,26 +108,24 @@ static void event_parse_params(struct event *event, const char *buf, int len)
 
 int event_parse_ad_message(struct event *event, char *buf, int len)
 {
-       int result;
-       char *device;
        enum event_action action;
-       int device_len;
+       int headerlen;
+       char *device;
 
-       result = event_parse_ad_header(buf, len, &action, &device);
+       headerlen = event_parse_ad_header(buf, len, &action, &device);
 
-       if (result)
+       if (headerlen <= 0)
                return -1;
 
-       device_len = strlen(device);
-
        /* now we have an action and a device, we can construct the event */
        event->action = action;
-       event->device = talloc_strndup(event, device, device_len);
+       event->device = talloc_strdup(event, device);
        event->n_params = 0;
        event->params = NULL;
 
-       len -= device_len + 1;
-       event_parse_params(event, device + device_len + 1, len);
+       len -= headerlen + 1;
+       buf += headerlen + 1;
+       event_parse_params(event, buf, len);
 
        return 0;
 }