From: Sven Eckelmann <[email protected]> pskb_may_pull() in batadv_interface_rx() could reallocate the buffer behind the skb. Variables which were pointing to the old buffer need to be reassigned to avoid an use-after-free.
This was done correctly for the VLAN header but missed for the ethernet header which is later used for the TT and AP isolation handling. Cc: [email protected] Reported-by: Sashiko <[email protected]> Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol") Fixes: c78296665c3d ("batman-adv: Check skb size before using encapsulated ETH+VLAN header") Signed-off-by: Sven Eckelmann <[email protected]> Signed-off-by: Simon Wunderlich <[email protected]> --- net/batman-adv/mesh-interface.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/batman-adv/mesh-interface.c b/net/batman-adv/mesh-interface.c index 44026810b99ce..511f70e0706a7 100644 --- a/net/batman-adv/mesh-interface.c +++ b/net/batman-adv/mesh-interface.c @@ -434,6 +434,7 @@ void batadv_interface_rx(struct net_device *mesh_iface, if (!pskb_may_pull(skb, VLAN_ETH_HLEN)) goto dropped; + ethhdr = eth_hdr(skb); vhdr = skb_vlan_eth_hdr(skb); /* drop batman-in-batman packets to prevent loops */ -- 2.47.3
