From nobody Fri Sep 25 02:44:21 2026 Received: from cstnet.cn (smtp25.cstnet.cn [159.226.251.25]) (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 A169F4E1C7E; Thu, 17 Sep 2026 11:56:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.25 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789646225; cv=none; b=s8qEvC3/ue1YrS1GbQq3OO1yROufeKMLz9LDZoS2wAeSVPan0Yq9ZJHwbbcjkwAttBXxaMgZmUUBH8w+wyLVT0XqMAyWDb8qqi5+cfO4F9pZFaEq44GtSev/ReVI9QSS8QyIgHhZkqGTNUCxTCRJ3wA972KfzzPLrOvzOILu7BQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789646225; c=relaxed/simple; bh=LQSAMvuMIXoFBsB3EoBPRj/v5VaC1ztq+/z7kXIde2M=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=dA391eDePld2DUR7xQ4tjSyz7tZSoWiUpIJZzpZWnYDr6l0EDWwTDgHJ6F/JxYmKqdfMXbTwQ10A0gir6vJRKjb2VZBSmNyp92NDkZPrnYhioHzAoRxaOJTGmHnkSULJw8ehUCjbhSGfuTNAPWJCzX1ErK/dwtOr28CRDEndcmM= 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=159.226.251.25 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 [36.110.52.2]) by APP-05 (Coremail) with SMTP id zQCowAB3qEJ01atq7wOACA--.2128S2; Thu, 17 Sep 2026 19:56:36 +0800 (CST) From: Wentao Liang To: andrew+netdev@lunn.ch Cc: antonio@openvpn.net, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, sd@queasysnail.net, Wentao Liang , stable@vger.kernel.org Subject: [PATCH] ovpn: Fix use-after-free when releasing peers in unlock_ovpn() Date: Thu, 17 Sep 2026 11:56:36 +0000 Message-Id: <20260917115636.2150032-1-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: zQCowAB3qEJ01atq7wOACA--.2128S2 X-Coremail-Antispam: 1UD129KBjvJXoW7Xw47JFy8WryDZw4fuF1DAwb_yoW8JrWfpF 4rGr47JrykJr40qa1kGF1DWFyF93W3K34YkFyqk34fZrnxtr1YqryxJwnF93s8trZ3Wa1Y va1qyF15AayUArJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPmb7Iv0xC_tr1lb4IE77IF4wAFc2x0x2IEx4CE42xK8VAvwI8I cIk0rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2 AK021l84ACjcxK6xIIjxv20xvE14v26ryj6F1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v2 6r4UJVWxJr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI 0_GcCE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2Wl Yx0E2Ix0cI8IcVAFwI0_Jw0_WrylYx0Ex4A2jsIE14v26r4UJVWxJr1lOx8S6xCaFVCjc4 AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq62Iq12xI8VA0II8E6IAqYI8I648v4I1l FIxGxcIEc7CjxVA2Y2ka0xkIwI1lc7CjxVAaw2AFwI0_Jw0_GFyl42xK82IYc2Ij64vIr4 1l42xK82IY6x8ErcxFaVAv8VW8GFyrJr1UJwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s02 6c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw 0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUCVW8JwCI42IY6xIIjxv20xvE c7CjxVAFwI0_Cr0_Gr1UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67 AKxVW8Jr0_Cr1UMIIF0xvEx4A2jsIEc7CjxVAFwI0_GcCE3sUvcSsGvfC2KfnxnUUI43ZE Xa7IU878n5UUUUU== X-CM-SenderInfo: pyxotu46lvutnvoduhdfq/1tbiBgYNA2qrq3aEGQAAsP Content-Type: text/plain; charset="utf-8" unlock_ovpn() walks the release list with llist_for_each_entry() and drops the last reference of each peer in the loop body. Advancing to the next entry then reads peer->release_entry.next from an object that has already been scheduled for freeing, which is a use-after-free. Use llist_for_each_entry_safe() so the next pointer is read before the peer is released. Fixes: 80747caef33d ("ovpn: introduce the ovpn_peer object") Cc: stable@vger.kernel.org Signed-off-by: Wentao Liang --- drivers/net/ovpn/peer.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index a09d61296425..12ebc5affdd0 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -26,11 +26,11 @@ static void unlock_ovpn(struct ovpn_priv *ovpn, struct llist_head *release_list) __releases(&ovpn->lock) { - struct ovpn_peer *peer; + struct ovpn_peer *peer, *tmp; =20 spin_unlock_bh(&ovpn->lock); =20 - llist_for_each_entry(peer, release_list->first, release_entry) { + llist_for_each_entry_safe(peer, tmp, release_list->first, release_entry) { ovpn_socket_release(peer); ovpn_peer_put(peer); } --=20 2.34.1