[PATCH 2/5] batman-adv: update data pointers after skb_cow()
From: Simon Wunderlich <hidden>
Date: 2018-03-19 16:37:23
Also in:
batman
Subsystem:
batman advanced, the rest · Maintainers:
Marek Lindner, Simon Wunderlich, Antonio Quartulli, Sven Eckelmann, Linus Torvalds
From: Matthias Schiffer <mschiffer-Nyw9WiXk/RKXhJHkyCwd5uTW4wlIGRCZ@public.gmane.org>
batadv_check_unicast_ttvn() calls skb_cow(), so pointers into the SKB data
must be (re)set after calling it. The ethhdr variable is dropped
altogether.
Fixes: 7cdcf6dddc42 ("batman-adv: add UNICAST_4ADDR packet type")
Signed-off-by: Matthias Schiffer <mschiffer-Nyw9WiXk/RKXhJHkyCwd5uTW4wlIGRCZ@public.gmane.org>
Signed-off-by: Sven Eckelmann <redacted>
Signed-off-by: Simon Wunderlich <redacted>
---
net/batman-adv/routing.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c
index b6891e8b741c..6a9242658c8d 100644
--- a/net/batman-adv/routing.c
+++ b/net/batman-adv/routing.c@@ -968,14 +968,10 @@ int batadv_recv_unicast_packet(struct sk_buff *skb, struct batadv_orig_node *orig_node = NULL, *orig_node_gw = NULL; int check, hdr_size = sizeof(*unicast_packet); enum batadv_subtype subtype; - struct ethhdr *ethhdr; int ret = NET_RX_DROP; bool is4addr, is_gw; unicast_packet = (struct batadv_unicast_packet *)skb->data; - unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data; - ethhdr = eth_hdr(skb); - is4addr = unicast_packet->packet_type == BATADV_UNICAST_4ADDR; /* the caller function should have already pulled 2 bytes */ if (is4addr)
@@ -995,12 +991,14 @@ int batadv_recv_unicast_packet(struct sk_buff *skb, if (!batadv_check_unicast_ttvn(bat_priv, skb, hdr_size)) goto free_skb; + unicast_packet = (struct batadv_unicast_packet *)skb->data; + /* packet for me */ if (batadv_is_my_mac(bat_priv, unicast_packet->dest)) { /* If this is a unicast packet from another backgone gw, * drop it. */ - orig_addr_gw = ethhdr->h_source; + orig_addr_gw = eth_hdr(skb)->h_source; orig_node_gw = batadv_orig_hash_find(bat_priv, orig_addr_gw); if (orig_node_gw) { is_gw = batadv_bla_is_backbone_gw(skb, orig_node_gw,
@@ -1015,6 +1013,8 @@ int batadv_recv_unicast_packet(struct sk_buff *skb, } if (is4addr) { + unicast_4addr_packet = + (struct batadv_unicast_4addr_packet *)skb->data; subtype = unicast_4addr_packet->subtype; batadv_dat_inc_counter(bat_priv, subtype);
--
2.11.0