add some error checking

diff --git a/src/switch_xml.c b/src/switch_xml.c
index 8df8b77c069447f1ba46c881d5e211cbcb1af3dd..efaede83fb7c997df848828275754205334d537d 100644 (file)
--- a/src/switch_xml.c
+++ b/src/switch_xml.c
@@ -1157,11 +1157,17 @@ SWITCH_DECLARE(switch_xml_t) switch_xml_parse_fd(int fd)
                return NULL;
        fstat(fd, &st);
 
+       if (!st.st_size) {
+               return NULL;
+       }
+
 #ifdef HAVE_MMAP
        l = (st.st_size + sysconf(_SC_PAGESIZE) - 1) & ~(sysconf(_SC_PAGESIZE) - 1);
        if ((m = mmap(NULL, l, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0)) != MAP_FAILED) {
                madvise(m, l, MADV_SEQUENTIAL); /* optimize for sequential access */
-               root = (switch_xml_root_t) switch_xml_parse_str(m, st.st_size);
+               if (!(root = (switch_xml_root_t) switch_xml_parse_str(m, st.st_size))) {
+                       munmap(m, l);
+               }
                madvise(m, root->len = l, MADV_NORMAL); /* put it back to normal */
        } else {                                        /* mmap failed, read file into memory */
 #endif /* HAVE_MMAP */
@@ -1169,7 +1175,10 @@ SWITCH_DECLARE(switch_xml_t) switch_xml_parse_fd(int fd)
                if (!m)
                        return NULL;
                l = read(fd, m, st.st_size);
-               root = (switch_xml_root_t) switch_xml_parse_str((char *) m, l);
+               if (!l || !(root = (switch_xml_root_t) switch_xml_parse_str((char *) m, l))) {
+                       free(m);
+                       return NULL;
+               }
                root->dynamic = 1;              /* so we know to free s in switch_xml_free() */
 #ifdef HAVE_MMAP
        }