Ticket #1483: mod_magnet_length.patch

src/mod_magnet.c

@@ -580 +580 @@
                                                 if (lua_isnumber(L, -2)) {
                                                         len = lua_tonumber(L, -2);
                                                 } else {
-                                                        len = sce->st.st_size;
+                                                        len = sce->st.st_size - off;
                                                 }
 
                                                 if (off < 0) {
                                                         return luaL_error(L, "offset for '%s' is negative", fn->ptr);
                                                 }
 
-                                                if (len < off) {
-                                                        return luaL_error(L, "offset > length for '%s'", fn->ptr);
+                                                if (len < 0) {
+                                                        return luaL_error(L, "length for '%s' is negative", fn->ptr);
                                                 }
 
-                                                chunkqueue_append_file(con->write_queue, fn, off, len - off);
+                                                if (sce->st.st_size < off + len) {
+                                                        return luaL_error(L, "file too small; length + offset > filesize for '%s'", fn->ptr);
+                                                }
+
+                                                if (len != 0) {
+                                                        chunkqueue_append_file(con->write_queue, fn, off, len);
+                                                }
                                         }
 
                                         buffer_free(fn);