.

wcfs/client/wcfs_watchlink.cpp

@@ -135,9 +135,8 @@ error _WatchLink::_serveRX(context::Context ctx) {
 
     while (1) {
         // NOTE: .close() makes sure .f.read*() will wake up
-        //printf("serveRX -> readline ...\n");
-        tie(l, err) = wlink._readline();    // XXX +maxlen
-        //printf("    readline -> woken up; l='%s'  ; err='%s'\n", v(l), v(err));
+        tie(l, err) = wlink._readline();
+        //trace("    readline -> l='%s'  ; err='%s'\n", v(l), v(err));
         if (err == io::EOF_) {  // peer closed its tx
             // XXX what happens on other errors?
             wlink.rx_eof.close();
@@ -416,19 +415,21 @@ tuple<string, error> _WatchLink::_readline() {
         if (nl != string::npos) {
             auto line = wlink._rxbuf.substr(0, nl+1);
             wlink._rxbuf = wlink._rxbuf.substr(nl+1);
-            //printf("\t_readline -> ret '%s'\n", v(line));
+            //trace("\t_readline -> ret '%s'\n", v(line));
             return make_tuple(line, nil);
         }
         nl_searchfrom = wlink._rxbuf.length();
 
         int n;
         error err;
-        //printf("\t_readline -> read ...\n");
+        //trace("\t_readline -> read ...\n");
         tie(n, err) = wlink._f->read(buf, sizeof(buf));
-        //printf("\t_readline -> read: n=%d  err='%s'\n", n, v(err));
+        //trace("\t_readline -> read: n=%d  err='%s'\n", n, v(err));
         if (n > 0) {
-            // XXX limit line length to avoid DoS
             wlink._rxbuf += string(buf, n);
+            // limit line length to avoid DoS
+            if (wlink._rxbuf.length() > 128) // XXX limit arbitrary
+                return make_tuple("", fmt::errorf("line is too long"));
             continue;
         }
         if (err == nil)