From mboxrd@z Thu Jan 1 00:00:00 1970 From: Antonio Quartulli Subject: [PATCH 03/16] batman-adv: Check total_size when queueing fragments Date: Fri, 29 May 2015 11:05:15 +0200 Message-ID: <1432890328-8247-4-git-send-email-antonio@meshcoding.com> References: <1432890328-8247-1-git-send-email-antonio@meshcoding.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: netdev@vger.kernel.org, b.a.t.m.a.n@lists.open-mesh.org, Sven Eckelmann , Marek Lindner , Antonio Quartulli To: davem@davemloft.net Return-path: Received: from s1.neomailbox.net ([5.148.176.57]:14791 "EHLO s1.neomailbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030207AbbE2Jcm (ORCPT ); Fri, 29 May 2015 05:32:42 -0400 In-Reply-To: <1432890328-8247-1-git-send-email-antonio@meshcoding.com> Sender: netdev-owner@vger.kernel.org List-ID: =46rom: Sven Eckelmann The fragmentation code was replaced in 610bfc6bc99bc83680d190ebc69359a05fc7f605 ("batman-adv: Receive fragment= ed packets and merge") by an implementation which handles the queueing+mer= ging of fragments based on their size and the total_size of the non-fragment= ed packet. This total_size is announced by each fragment. The new implementation doesn't check if the the total_size information of the packets inside one chain is consistent. This is consistency check is recommended to allow using any of the pack= ets in the queue to decide whether all fragments of a packet are received o= r not. Signed-off-by: Sven Eckelmann Acked-by: Martin Hundeb=C3=B8ll Signed-off-by: Marek Lindner Signed-off-by: Antonio Quartulli --- net/batman-adv/fragmentation.c | 7 +++++-- net/batman-adv/types.h | 2 ++ 2 files changed, 7 insertions(+), 2 deletions(-) diff --git a/net/batman-adv/fragmentation.c b/net/batman-adv/fragmentat= ion.c index af495cc..a9fc653 100644 --- a/net/batman-adv/fragmentation.c +++ b/net/batman-adv/fragmentation.c @@ -161,6 +161,7 @@ static bool batadv_frag_insert_packet(struct batadv= _orig_node *orig_node, hlist_add_head(&frag_entry_new->list, &chain->head); chain->size =3D skb->len - hdr_size; chain->timestamp =3D jiffies; + chain->total_size =3D ntohs(frag_packet->total_size); ret =3D true; goto out; } @@ -195,9 +196,11 @@ static bool batadv_frag_insert_packet(struct batad= v_orig_node *orig_node, =20 out: if (chain->size > batadv_frag_size_limit() || - ntohs(frag_packet->total_size) > batadv_frag_size_limit()) { + chain->total_size !=3D ntohs(frag_packet->total_size) || + chain->total_size > batadv_frag_size_limit()) { /* Clear chain if total size of either the list or the packet - * exceeds the maximum size of one merged packet. + * exceeds the maximum size of one merged packet. Don't allow + * packets to have different total_size. */ batadv_frag_clear_chain(&chain->head); chain->size =3D 0; diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 28f2461..e95db42 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -132,6 +132,7 @@ struct batadv_orig_ifinfo { * @timestamp: time (jiffie) of last received fragment * @seqno: sequence number of the fragments in the list * @size: accumulated size of packets in list + * @total_size: expected size of the assembled packet */ struct batadv_frag_table_entry { struct hlist_head head; @@ -139,6 +140,7 @@ struct batadv_frag_table_entry { unsigned long timestamp; uint16_t seqno; uint16_t size; + uint16_t total_size; }; =20 /** --=20 2.4.2