1 files changed, 2 insertions, 1 deletions

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 81dc1bb6e016..f1ffb34e253f 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -2831,7 +2831,8 @@ static int netlink_dump(struct sock *sk)
          * reasonable static buffer based on the expected largest dump of a
          * single netdev. The outcome is MSG_TRUNC error.
          */
-        skb_reserve(skb, skb_tailroom(skb) - alloc_size);
+        if (!netlink_rx_is_mmaped(sk))
+                skb_reserve(skb, skb_tailroom(skb) - alloc_size);
         netlink_skb_set_owner_r(skb, sk);
 
         len = cb->dump(skb, cb);