From nobody Fri Oct 17 10:31:32 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B17EFC4332F for ; Wed, 19 Oct 2022 10:52:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234623AbiJSKw4 (ORCPT ); Wed, 19 Oct 2022 06:52:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43774 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234550AbiJSKw2 (ORCPT ); Wed, 19 Oct 2022 06:52:28 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DAFAC15DB36; Wed, 19 Oct 2022 03:23:38 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id B3F66B82390; Wed, 19 Oct 2022 08:51:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2DF16C433D6; Wed, 19 Oct 2022 08:51:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666169498; bh=7h9aWcGCfgx2rKr3+DGUU7gZV0M1EwXuVeR7W2iK1KQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1Mb57gMi8Zzw+vx0lh0NZZ1XWGIowbwIVVwpLD8EQYaZMjke31LhZ8ntiNMtI5D9+ fEn1tf5E72VzLjNq6rtGIXKYHyPvQgFhp4EAsYXfn43SG+zTt05e6zGI8I41B5fZn0 gmgH/lT8KzNE5XZ4BZKzvQamthMI7M9tgZDfgeiE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot , Tetsuo Handa , Luiz Augusto von Dentz , Sasha Levin Subject: [PATCH 6.0 298/862] Bluetooth: hci_{ldisc,serdev}: check percpu_init_rwsem() failure Date: Wed, 19 Oct 2022 10:26:25 +0200 Message-Id: <20221019083303.176643973@linuxfoundation.org> X-Mailer: git-send-email 2.38.0 In-Reply-To: <20221019083249.951566199@linuxfoundation.org> References: <20221019083249.951566199@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Tetsuo Handa [ Upstream commit 3124d320c22f3f4388d9ac5c8f37eaad0cefd6b1 ] syzbot is reporting NULL pointer dereference at hci_uart_tty_close() [1], for rcu_sync_enter() is called without rcu_sync_init() due to hci_uart_tty_open() ignoring percpu_init_rwsem() failure. While we are at it, fix that hci_uart_register_device() ignores percpu_init_rwsem() failure and hci_uart_unregister_device() does not call percpu_free_rwsem(). Link: https://syzkaller.appspot.com/bug?extid=3D576dfca25381fb6fbc5f [1] Reported-by: syzbot Signed-off-by: Tetsuo Handa Fixes: 67d2f8781b9f00d1 ("Bluetooth: hci_ldisc: Allow sleeping while proto = locks are held.") Fixes: d73e172816652772 ("Bluetooth: hci_serdev: Init hci_uart proto_lock t= o avoid oops") Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin --- drivers/bluetooth/hci_ldisc.c | 7 +++++-- drivers/bluetooth/hci_serdev.c | 10 +++++++--- 2 files changed, 12 insertions(+), 5 deletions(-) diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c index f537673ede17..865112e96ff9 100644 --- a/drivers/bluetooth/hci_ldisc.c +++ b/drivers/bluetooth/hci_ldisc.c @@ -493,6 +493,11 @@ static int hci_uart_tty_open(struct tty_struct *tty) BT_ERR("Can't allocate control structure"); return -ENFILE; } + if (percpu_init_rwsem(&hu->proto_lock)) { + BT_ERR("Can't allocate semaphore structure"); + kfree(hu); + return -ENOMEM; + } =20 tty->disc_data =3D hu; hu->tty =3D tty; @@ -505,8 +510,6 @@ static int hci_uart_tty_open(struct tty_struct *tty) INIT_WORK(&hu->init_ready, hci_uart_init_work); INIT_WORK(&hu->write_work, hci_uart_write_work); =20 - percpu_init_rwsem(&hu->proto_lock); - /* Flush any pending characters in the driver */ tty_driver_flush_buffer(tty); =20 diff --git a/drivers/bluetooth/hci_serdev.c b/drivers/bluetooth/hci_serdev.c index c0e5f42ec6b7..f16fd79bc02b 100644 --- a/drivers/bluetooth/hci_serdev.c +++ b/drivers/bluetooth/hci_serdev.c @@ -310,11 +310,12 @@ int hci_uart_register_device(struct hci_uart *hu, =20 serdev_device_set_client_ops(hu->serdev, &hci_serdev_client_ops); =20 + if (percpu_init_rwsem(&hu->proto_lock)) + return -ENOMEM; + err =3D serdev_device_open(hu->serdev); if (err) - return err; - - percpu_init_rwsem(&hu->proto_lock); + goto err_rwsem; =20 err =3D p->open(hu); if (err) @@ -389,6 +390,8 @@ int hci_uart_register_device(struct hci_uart *hu, p->close(hu); err_open: serdev_device_close(hu->serdev); +err_rwsem: + percpu_free_rwsem(&hu->proto_lock); return err; } EXPORT_SYMBOL_GPL(hci_uart_register_device); @@ -410,5 +413,6 @@ void hci_uart_unregister_device(struct hci_uart *hu) clear_bit(HCI_UART_PROTO_READY, &hu->flags); serdev_device_close(hu->serdev); } + percpu_free_rwsem(&hu->proto_lock); } EXPORT_SYMBOL_GPL(hci_uart_unregister_device); --=20 2.35.1