3.5.7.2 -stable review patch. If anyone has any objections, please let me know.
------------------ From: =?UTF-8?q?Linus=20L=C3=BCssing?= <[email protected]> commit 7f112af40fecf5399b61e69ffc6b55a9d82789f7 upstream. So far the crc16 checksum for a batman-adv broadcast data packet, received on a batman-adv hard interface, was calculated over zero bytes of its content leading to many incoming broadcast data packets wrongly being dropped (60-80% packet loss). This patch fixes this issue by calculating the crc16 over the actual, complete broadcast payload. The issue is a regression introduced by ("batman-adv: add broadcast duplicate check"). Signed-off-by: Linus Lüssing <[email protected]> Acked-by: Simon Wunderlich <[email protected]> Signed-off-by: Marek Lindner <[email protected]> [ herton: use backported version provided on stable mailing list, but drop unrelated comment change ] Signed-off-by: Herton Ronaldo Krzesinski <[email protected]> --- net/batman-adv/bridge_loop_avoidance.c | 8 ++++---- net/batman-adv/routing.c | 8 +++++++- 2 files changed, 11 insertions(+), 5 deletions(-) diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c index c5863f4..2531044 100644 --- a/net/batman-adv/bridge_loop_avoidance.c +++ b/net/batman-adv/bridge_loop_avoidance.c @@ -1172,8 +1172,8 @@ int bla_init(struct bat_priv *bat_priv) /** * @bat_priv: the bat priv with all the soft interface information - * @bcast_packet: originator mac address - * @hdr_size: maximum length of the frame + * @bcast_packet: encapsulated broadcast frame plus batman header + * @bcast_packet_len: length of encapsulated broadcast frame plus batman header * * check if it is on our broadcast list. Another gateway might * have sent the same packet because it is connected to the same backbone, @@ -1188,14 +1188,14 @@ int bla_init(struct bat_priv *bat_priv) int bla_check_bcast_duplist(struct bat_priv *bat_priv, struct bcast_packet *bcast_packet, - int hdr_size) + int bcast_packet_len) { int i, length, curr; uint8_t *content; uint16_t crc; struct bcast_duplist_entry *entry; - length = hdr_size - sizeof(*bcast_packet); + length = bcast_packet_len - sizeof(*bcast_packet); content = (uint8_t *)bcast_packet; content += sizeof(*bcast_packet); diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index 015471d..af40ca3 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -1081,8 +1081,14 @@ int recv_bcast_packet(struct sk_buff *skb, struct hard_iface *recv_if) spin_unlock_bh(&orig_node->bcast_seqno_lock); + /* keep skb linear for crc calculation */ + if (skb_linearize(skb) < 0) + goto out; + + bcast_packet = (struct bcast_packet *)skb->data; + /* check whether this has been sent by another originator before */ - if (bla_check_bcast_duplist(bat_priv, bcast_packet, hdr_size)) + if (bla_check_bcast_duplist(bat_priv, bcast_packet, skb->len)) goto out; /* rebroadcast packet */ -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
