From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-ID: <547C534E.5010405@hundeboll.net> Date: Mon, 01 Dec 2014 12:38:54 +0100 From: =?windows-1252?Q?Martin_Hundeb=F8ll?= MIME-Version: 1.0 References: <1417426648-9319-1-git-send-email-sven@narfation.org> In-Reply-To: <1417426648-9319-1-git-send-email-sven@narfation.org> Content-Type: text/plain; charset="windows-1252"; format="flowed" Content-Transfer-Encoding: quoted-printable Subject: Re: [B.A.T.M.A.N.] [PATCHv3 1/2] 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: The list for a Better Approach To Mobile Ad-hoc Networking Cc: Sven Eckelmann Hi, On 2014-12-01 10:37, Sven Eckelmann wrote: > The fragmentation code was replaced in 9b3eab61754d74a93c9840c296013fe3b4= a1b606 > ("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 packet= s in > the queue to decide whether all fragments of a packet are received or not. > > Signed-off-by: Sven Eckelmann > --- > This is only compile tested > > v3. > - withdrawing from inclusion in maint > - remove wrong example from the commit message > v2: > - proposed for maint > - changed commit message slightly > --- > fragmentation.c | 7 +++++-- > types.h | 2 ++ > 2 files changed, 7 insertions(+), 2 deletions(-) > > diff --git a/fragmentation.c b/fragmentation.c > index 5251aa1..6e4c957 100644 > --- a/fragmentation.c > +++ b/fragmentation.c > @@ -161,6 +161,7 @@ static bool batadv_frag_insert_packet(struct batadv_o= rig_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 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 !=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/types.h b/types.h > index 462a70c..c4d7d24 100644 > --- a/types.h > +++ b/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; > }; > > /** > As with the first version: Acked-by: Martin Hundeb=F8ll