diff --git a/ndpi-netfilter/src/ndpi_proc_generic.c b/ndpi-netfilter/src/ndpi_proc_generic.c
index 4dba9f28e..91a34f95d 100644
--- a/ndpi-netfilter/src/ndpi_proc_generic.c
+++ b/ndpi-netfilter/src/ndpi_proc_generic.c
@@ -78,25 +78,25 @@ generic_proc_write(struct ndpi_net *n, const char __user *buffer,
 	skip = w_buf->cpos == w_buf->max - 1;
 
 	while(pos < length) {
-		l = min(length,sizeof(buf)-1);
+		l = min(length-pos,sizeof(buf)-1);
 	
 		memset(buf,0,sizeof(buf));
 		if (!(ACCESS_OK(VERIFY_READ, buffer+pos, l) && 
 			!__copy_from_user(&buf[0], buffer+pos, l)))
 			        return -EFAULT;
-		for(i = 0; i < l; i++) {
+		for(i = 0; i < l; (*loff)++,i++) {
 			c = buf[i];
 			if(c == '\n' || !c) {
 				if(w_buf->cpos) {
 					if(ndpi_log_debug > 1)
-					    pr_info("%s:%s cmd %d:%s\n", __func__,n->ns_name,
-							    w_buf->cpos,&w_buf->cmd[0]);
+					    pr_info("%s:%s POS %lld cmd %d:'%s' i %d\n", __func__,n->ns_name,
+							   *loff,w_buf->cpos,&w_buf->cmd[0],i);
 					r = (parse_line)(n,&w_buf->cmd[0]);
+					memset(&w_buf->cmd[0],0,w_buf->cpos);
+					skip = 0;
+					w_buf->cpos = 0;
+					if(r) return -EINVAL;
 				}
-				skip = 0;
-				w_buf->cpos = 0;
-				memset(&w_buf->cmd[0],0,cmd_size);
-				if(r) return -EINVAL;
 			} else {
 				if(w_buf->cpos < w_buf->max - 1)
 					w_buf->cmd[w_buf->cpos++] = c;