From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Antonio Quartulli Date: Fri, 29 May 2015 11:05:15 +0200 Message-Id: <1432890328-8247-4-git-send-email-antonio@meshcoding.com> In-Reply-To: <1432890328-8247-1-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: 8bit Subject: [B.A.T.M.A.N.] [PATCH 03/16] batman-adv: Check total_size when queueing fragments Reply-To: The list for a Better Approach To Mobile Ad-hoc Networking List-Id: The list for a Better Approach To Mobile Ad-hoc Networking List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: davem@davemloft.net Cc: netdev@vger.kernel.org, b.a.t.m.a.n@lists.open-mesh.org, Antonio Quartulli , Marek Lindner From: Sven Eckelmann The fragmentation code was replaced in 610bfc6bc99bc83680d190ebc69359a05fc7f605 ("batman-adv: Receive fragmented packets and merge") by an implementation which handles the queueing+merging of fragments based on their size and the total_size of the non-fragmented 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 packets in the queue to decide whether all fragments of a packet are received or not. Signed-off-by: Sven Eckelmann Acked-by: Martin Hundebøll 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/fragmentation.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 = skb->len - hdr_size; chain->timestamp = jiffies; + chain->total_size = ntohs(frag_packet->total_size); ret = true; goto out; } @@ -195,9 +196,11 @@ static bool batadv_frag_insert_packet(struct batadv_orig_node *orig_node, out: if (chain->size > batadv_frag_size_limit() || - ntohs(frag_packet->total_size) > batadv_frag_size_limit()) { + chain->total_size != 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 = 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; }; /** -- 2.4.2