From nobody Fri Sep 25 05:29:52 2026 Received: from cstnet.cn (smtp81.cstnet.cn [159.226.251.81]) (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 8663E4AEBEF; Wed, 16 Sep 2026 09:48:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.81 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789552149; cv=none; b=sdjGSxLfU6Unmzm5HFKeifs2+VyIsb1JsIEJ+XIiDj3SnPl1RF2XtBzJPajg0iP7CsmiaXqyREcemJoM0asTsYC6+y/7VoIYxr3yuwEEv66MmXTP/KubNz231mZxsbZFzodFqRoqjiEA6hANmCeq71ciSovAtalcIUDrg7v4iPk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789552149; c=relaxed/simple; bh=yNZKSeD9djGtz5o/sJAjhbLIc6ZrYenwtSjaIgHcp50=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=U8lWLRMx0SvOjKHiBsDpF0hkOjgXLN+i1N87cYQoXPMw1TV0H4sadLaLXxK4Xm+tAzQya/59S5oC/6pWV5b9bJL1KtBFFN9WBgv4X+da6Gyx0kFFSeXS19zPy93kZWbjkra/p84XsNq+coD6MDeIXUjyd/77nk/lH0NwB7ePG0M= 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=159.226.251.81 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-03 (Coremail) with SMTP id rQCowACXmjj9ZapqLKXgBw--.61487S2; Wed, 16 Sep 2026 17:48:45 +0800 (CST) From: Wentao Liang To: axboe@kernel.dk Cc: bvanassche@acm.org, danil.kipnis@cloud.ionos.com, haris.iqbal@ionos.com, jgg@ziepe.ca, jinpu.wang@ionos.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Wentao Liang , stable@vger.kernel.org Subject: [PATCH] rnbd-srv: Fix sess_dev use-after-free in process_msg_close() Date: Wed, 16 Sep 2026 09:48:17 +0000 Message-Id: <20260916094817.2007756-1-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: rQCowACXmjj9ZapqLKXgBw--.61487S2 X-Coremail-Antispam: 1UD129KBjvJXoW7AF1fAFW8Kr47JFy3uF17Wrg_yoW8GFyxpa y0y3Wj9ryFkF4UG3yDZw4xuFWYyan2y3y8Cr1xur1UZ345ZFy2vFn3X34xJF1qqry8Can0 qFn5JayrCw1Yya7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9a14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26F1j6w1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4U JVWxJr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Gc CE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E 2Ix0cI8IcVAFwI0_Jw0_WrylYx0Ex4A2jsIE14v26r4UJVWxJr1lOx8S6xCaFVCjc4AY6r 1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02 628vn2kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4 IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1r MI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUCV W8JwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Cr0_Gr1UMIIF0xvE42xK8VAvwI8IcIk0rVWU JVWUCwCI42IY6I8E87Iv67AKxVW8JVWxJwCI42IY6I8E87Iv6xkF7I0E14v26r4UJVWxJr UvcSsGvfC2KfnxnUUI43ZEXa7VUbtl1PUUUUU== X-CM-SenderInfo: pyxotu46lvutnvoduhdfq/1tbiCRIMA2qqP4efBQAAs2 Content-Type: text/plain; charset="utf-8" process_msg_close() drops the device reference with rnbd_put_sess_dev() before using sess_dev again in rnbd_srv_destroy_dev_session_sysfs(). If that put drops the last kref, e.g. when the device is concurrently being torn down through rnbd_srv_sess_dev_force_close(), the waiter in rnbd_destroy_sess_dev() is woken up and frees sess_dev, so the subsequent rnbd_srv_destroy_dev_session_sysfs() call operates on freed memory. Move the rnbd_put_sess_dev() call after the sysfs teardown so it is the last access to sess_dev. Fixes: 2de6c8de192b ("block/rnbd: server: main functionality") Cc: stable@vger.kernel.org Signed-off-by: Wentao Liang --- drivers/block/rnbd/rnbd-srv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/block/rnbd/rnbd-srv.c b/drivers/block/rnbd/rnbd-srv.c index 10e8c438bb43..2ebc2eac384f 100644 --- a/drivers/block/rnbd/rnbd-srv.c +++ b/drivers/block/rnbd/rnbd-srv.c @@ -361,10 +361,10 @@ static void process_msg_close(struct rnbd_srv_session= *srv_sess, if (IS_ERR(sess_dev)) return; =20 - rnbd_put_sess_dev(sess_dev); mutex_lock(&srv_sess->lock); rnbd_srv_destroy_dev_session_sysfs(sess_dev); mutex_unlock(&srv_sess->lock); + rnbd_put_sess_dev(sess_dev); } =20 static int process_msg_open(struct rnbd_srv_session *srv_sess, --=20 2.34.1