From bc0fcb9823cd0894934cf968b525c575833d7078 Mon Sep 17 00:00:00 2001 From: Yilin Zhu Date: Sun, 12 Apr 2026 13:07:54 +0800 Subject: [PATCH] ipv6: xfrm6: release dst on error in xfrm6_rcv_encap() xfrm6_rcv_encap() performs an IPv6 route lookup when the skb does not already have a dst attached. ip6_route_input_lookup() returns a referenced dst entry even when the lookup resolves to an error route. If dst->error is set, xfrm6_rcv_encap() drops the skb without attaching the dst to the skb and without releasing the reference returned by the lookup. Repeated packets hitting this path therefore leak dst entries. Release the dst before jumping to the drop path. Fixes: 0146dca70b87 ("xfrm: add support for UDPv6 encapsulation of ESP") Cc: stable@kernel.org Reported-by: Yifan Wu Reported-by: Juefei Pu Co-developed-by: Yuan Tan Signed-off-by: Yuan Tan Suggested-by: Xin Liu Tested-by: Ruide Cao Signed-off-by: Yilin Zhu Signed-off-by: Ren Wei Reviewed-by: Simon Horman Signed-off-by: Steffen Klassert --- net/ipv6/xfrm6_protocol.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/ipv6/xfrm6_protocol.c b/net/ipv6/xfrm6_protocol.c index ea2f805d3b01..9b586fcec485 100644 --- a/net/ipv6/xfrm6_protocol.c +++ b/net/ipv6/xfrm6_protocol.c @@ -88,8 +88,10 @@ int xfrm6_rcv_encap(struct sk_buff *skb, int nexthdr, __be32 spi, dst = ip6_route_input_lookup(dev_net(skb->dev), skb->dev, &fl6, skb, flags); - if (dst->error) + if (dst->error) { + dst_release(dst); goto drop; + } skb_dst_set(skb, dst); }