From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C5CBAC432C0 for ; Fri, 22 Nov 2019 10:35:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9E3C420715 for ; Fri, 22 Nov 2019 10:35:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574418922; bh=2GHJ6Ir6mspFPNcJwnTR9HqLEbOuLJQN5DVWsjltPR8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=MuC78tfXLhV/9I/AyFE8WXrt+gyQ1IKUv25QrMHdPT+/m+8c1sVKIrruXllg1Q44W Hb4DFU/26muRepVMUlS6qShPexXbyuPc56FzlGp0saVtBW5Ok5LyuI+RpEVgVFm07f JfsluCDvPvpCLmXcRTqfTaTyGKwQ+Br9iOf9e3KE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727696AbfKVKfV (ORCPT ); Fri, 22 Nov 2019 05:35:21 -0500 Received: from mail.kernel.org ([198.145.29.99]:33382 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727388AbfKVKfV (ORCPT ); Fri, 22 Nov 2019 05:35:21 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5ADD520708; Fri, 22 Nov 2019 10:35:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574418920; bh=2GHJ6Ir6mspFPNcJwnTR9HqLEbOuLJQN5DVWsjltPR8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ftv8eTFD3vvSQ4mXfAOc+h0IK0OAwcocxA5rUB4BiJod4DZQ5gYzypyCV5Z4r8pgg tWLcV/ZaNzW+OpIof5NDz2u3Os3ndaGb2pjb3znAyUauBMQ6jkABZfzWCTMOhCFXsA s2WfMO5/jZQN5ImhwfOBAbsYRLRCdwAQsjDCcmSI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+899a33dc0fa0dbaf06a6@syzkaller.appspotmail.com, Kefeng Wang , Jeremy Cline , Marcel Holtmann , Ralph Siemsen Subject: [PATCH 4.4 097/159] Bluetooth: hci_ldisc: Postpone HCI_UART_PROTO_READY bit set in hci_uart_set_proto() Date: Fri, 22 Nov 2019 11:28:08 +0100 Message-Id: <20191122100817.654793586@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191122100704.194776704@linuxfoundation.org> References: <20191122100704.194776704@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Kefeng Wang commit 56897b217a1d0a91c9920cb418d6b3fe922f590a upstream. task A: task B: hci_uart_set_proto flush_to_ldisc - p->open(hu) -> h5_open //alloc h5 - receive_buf - set_bit HCI_UART_PROTO_READY - tty_port_default_receive_buf - hci_uart_register_dev - tty_ldisc_receive_buf - hci_uart_tty_receive - test_bit HCI_UART_PROTO_READY - h5_recv - clear_bit HCI_UART_PROTO_READY while() { - p->open(hu) -> h5_close //free h5 - h5_rx_3wire_hdr - h5_reset() //use-after-free } It could use ioctl to set hci uart proto, but there is a use-after-free issue when hci_uart_register_dev() fail in hci_uart_set_proto(), see stack above, fix this by setting HCI_UART_PROTO_READY bit only when hci_uart_register_dev() return success. Reported-by: syzbot+899a33dc0fa0dbaf06a6@syzkaller.appspotmail.com Signed-off-by: Kefeng Wang Reviewed-by: Jeremy Cline Signed-off-by: Marcel Holtmann Cc: Ralph Siemsen Signed-off-by: Greg Kroah-Hartman --- drivers/bluetooth/hci_ldisc.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/drivers/bluetooth/hci_ldisc.c +++ b/drivers/bluetooth/hci_ldisc.c @@ -653,15 +653,14 @@ static int hci_uart_set_proto(struct hci return err; hu->proto = p; - set_bit(HCI_UART_PROTO_READY, &hu->flags); err = hci_uart_register_dev(hu); if (err) { - clear_bit(HCI_UART_PROTO_READY, &hu->flags); p->close(hu); return err; } + set_bit(HCI_UART_PROTO_READY, &hu->flags); return 0; }