From nobody Sun Feb 8 19:25:42 2026 Received: from cstnet.cn (smtp84.cstnet.cn [159.226.251.84]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AF7EE30DD12; Tue, 16 Dec 2025 03:37:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.84 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765856239; cv=none; b=lX+e/oobSPbaAdCb6MhXnCUvOnIQdNdZ/SJky4neZ3srylrTQY0Etx5StDYgpSXQCDKzb9K8amLnWohd0dWjYTX51yBgDDjILwZcCushmWZdMY2HJNqz+0ohUwVdneFgLdkXsyK7QVjg5w4LO6a8x/FGW4ytdFHpqhiEy09pcUE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765856239; c=relaxed/simple; bh=bAD7qxNiFLFdzt7WlIweVUEMW3vywq12f1bQwNdKBXo=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=eO1RgKm8dyrtWYTjseiQX4QKHw+RakOr23A4MX7AkTHikgadDeGWn5Tj/xRdj8CTf5nX5om5ZX4RnK4wsojdzG2onXCfx/AMHFTBDG68eWKqJHl0RzFKh+x1bhKqlwr9NcmKfbIGW2DlgevEGVl+VpNiQqS98uumRMra7l8jZdE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.84 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from dfae2b116770.home.arpa (unknown [124.16.138.129]) by APP-05 (Coremail) with SMTP id zQCowABX7A_Q00Bpk4rTAA--.50339S2; Tue, 16 Dec 2025 11:36:48 +0800 (CST) From: Wentao Liang To: andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com Cc: razor@blackwall.org, petrm@nvidia.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Wentao Liang , stable@vger.kernel.org Subject: [PATCH] vxlan: fix dst ref count leak in the vxlan_xmit_one() error path Date: Tue, 16 Dec 2025 03:36:47 +0000 Message-Id: <20251216033647.1792250-1-vulab@iscas.ac.cn> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: zQCowABX7A_Q00Bpk4rTAA--.50339S2 X-Coremail-Antispam: 1UD129KBjvJXoW7WFWDGr47Xw1DZr1rur47CFg_yoW8XrWfpF 4v9398ZFW3J3yqqw4xJw1rXFWrKay0k34Ikr1vka4Fqw13A34DGa4q9Fy29rs0qrWxury5 Jr42gryrAF98ZrJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9K14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26ryj6F1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4j 6F4UM28EF7xvwVC2z280aVAFwI0_Cr1j6rxdM28EF7xvwVC2z280aVCY1x0267AKxVW0oV Cq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0 I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r 4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628v n2kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCY02Avz4vE14v_Gr4l42xK82IYc2Ij64vIr4 1l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK 67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI 8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK8VAv wI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14 v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjfUn9a9DUUUU X-CM-SenderInfo: pyxotu46lvutnvoduhdfq/1tbiDAgSA2lArg2VKgAAsg Content-Type: text/plain; charset="utf-8" In the vxlan_xmit_one(), when the encap_bypass_if_local() returns an error, the function jumps to out_unlock without releasing the dst reference obtained from the udp_tunnel_dst_lookup(). This causes a reference count leak in both IPv4 and IPv6 paths. Fix by calling the dst_release() before goto out_unlock in both error paths: - For IPv4: release &rt->dst - For IPv6: release ndst Fixes: 56de859e9967 ("vxlan: lock RCU on TX path") Cc: stable@vger.kernel.org Signed-off-by: Wentao Liang --- drivers/net/vxlan/vxlan_core.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c index dab864bc733c..41bbc92cc234 100644 --- a/drivers/net/vxlan/vxlan_core.c +++ b/drivers/net/vxlan/vxlan_core.c @@ -2479,8 +2479,10 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_= device *dev, err =3D encap_bypass_if_local(skb, dev, vxlan, AF_INET, dst_port, ifindex, vni, &rt->dst, rt->rt_flags); - if (err) + if (err) { + dst_release(&rt->dst); goto out_unlock; + } =20 if (vxlan->cfg.df =3D=3D VXLAN_DF_SET) { df =3D htons(IP_DF); @@ -2560,8 +2562,10 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_= device *dev, err =3D encap_bypass_if_local(skb, dev, vxlan, AF_INET6, dst_port, ifindex, vni, ndst, rt6i_flags); - if (err) + if (err) { + dst_release(ndst); goto out_unlock; + } } =20 err =3D skb_tunnel_check_pmtu(skb, ndst, --=20 2.34.1