Fix various memory management issues

[project/libubox.git] / blobmsg_json.c

diff --git a/blobmsg_json.c b/blobmsg_json.c
index 5713948..2e318b2 100644 (file)
--- a/blobmsg_json.c
+++ b/blobmsg_json.c
@@ -119,15 +119,22 @@ struct strbuf {
 
 static bool blobmsg_puts(struct strbuf *s, const char *c, int len)
 {
+       size_t new_len;
+       char *new_buf;
+
        if (len <= 0)
                return true;
 
        if (s->pos + len >= s->len) {
-               s->len += 16 + len;
-               s->buf = realloc(s->buf, s->len);
-               if (!s->buf)
+               new_len = s->len + 16 + len;
+               new_buf = realloc(s->buf, new_len);
+               if (!new_buf)
                        return false;
+
+               s->len = new_len;
+               s->buf = new_buf;
        }
+
        memcpy(s->buf + s->pos, c, len);
        s->pos += len;
        return true;
@@ -290,14 +297,18 @@ char *blobmsg_format_json_with_cb(struct blob_attr *attr, bool list, blobmsg_jso
 {
        struct strbuf s;
        bool array;
+       char *ret;
 
        s.len = blob_len(attr);
-       s.buf = malloc(s.len);
        s.pos = 0;
        s.custom_format = cb;
        s.priv = priv;
        s.indent = false;
 
+       s.buf = malloc(s.len);
+       if (!s.buf)
+               return NULL;
+
        if (indent >= 0) {
                s.indent = true;
                s.indent_level = indent;
@@ -316,8 +327,13 @@ char *blobmsg_format_json_with_cb(struct blob_attr *attr, bool list, blobmsg_jso
                return NULL;
        }
 
-       s.buf = realloc(s.buf, s.pos + 1);
-       s.buf[s.pos] = 0;
+       ret = realloc(s.buf, s.pos + 1);
+       if (!ret) {
+               free(s.buf);
+               return NULL;
+       }
+
+       ret[s.pos] = 0;
 
-       return s.buf;
+       return ret;
 }