From patchwork Tue Mar 23 08:32:20 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Archie Pusaka X-Patchwork-Id: 12157205 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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 EEEAEC433C1 for ; Tue, 23 Mar 2021 08:32:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9E856619B6 for ; Tue, 23 Mar 2021 08:32:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229761AbhCWIc2 (ORCPT ); Tue, 23 Mar 2021 04:32:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56200 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229693AbhCWIc1 (ORCPT ); Tue, 23 Mar 2021 04:32:27 -0400 Received: from mail-pg1-x549.google.com (mail-pg1-x549.google.com [IPv6:2607:f8b0:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9FCD3C061574 for ; Tue, 23 Mar 2021 01:32:26 -0700 (PDT) Received: by mail-pg1-x549.google.com with SMTP id j4so1259485pgs.18 for ; Tue, 23 Mar 2021 01:32:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=KtQvqrz3w6xBtTxWdXYr5PEiVwRgjP+6HysrGaoX6eU=; b=DlM4X9aAYWJc8Kcs/DrMzz5CAXYgCgxLO6eh8pdqDX8KSkfklA/9aW54+tDVNPAcHm wIw0s6/IXg/axF4KydHQHgM87VjUuPtVS8otmgkic5ye4vMJ1SgnNc+Ex61qzV/wKvTL JodG8sNLBwGvJvnnoP8B7d3xe4k4w/hGe2P1Slte6KbmxHtmB4Lg8KxLoKQMeH2joxmM 4CVtT8sLX4lAk5L/GL5pshLVYMczqGS+ySwTYJB3WpBbQttsElTZjg1fgXoRxlj4TFGY 6ZIu6I6hsJdbqZo9EctKYo1WfPFB019LRLA58gwe3NrH+WYYOvZeBEE1ZecCb7JDkCU/ GJfg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=KtQvqrz3w6xBtTxWdXYr5PEiVwRgjP+6HysrGaoX6eU=; b=WyCj2BivPANQhN/KvB18PeG9PiRAjdrkGQFuAfJj17csnM9WHRX4s25vt5n2gMo/kG 1wpCuov9qWxmgtKBR204ghSOP58BcLvfB0XIHz0G2ugNPBAfqk/gGvmDxwC6sEitVw6W SSdRujzr31SQ/1wZKyKr/vE5AZOeK/AdfeWiCoPoNsLbk5AJdHaYY6Ky/Rc5SH+WUUIw vP5MpMz7hDNeJa402GH8PmZZqQQ92GJ7zw2dVH5R2mfgUcnzIKQAcuxItYSAabBpfMPC sB4PeH+HBDXoP/tsqNXg9TNIUKJ6M3yID3Nb2W3w0hTjP2dWjTyamDYPr1RqlhNAJRKT A64w== X-Gm-Message-State: AOAM530chPMtQoeURyIS7JVPLI4VxEanuATsneEvN8TQom8Q683k9Ozk zjdGE59+IN9x7iEecih+ezXGdDjppVV+TMLaDrGVP4uceGIX8sWvs9Ru7W1aYCJ8OXJ6QNPCj10 JoWFpY0MiIuSh2TnNKEMz0oFtByw7/yyxEQh/pVRd9bRk5baYO4CPOlY7cY5MT2zHIHl73FYHvN gd X-Google-Smtp-Source: ABdhPJx/iVy/TATqUnzYQb+Zxn94peGSevSjnAX+s+QI7WSRkdje6wmgQl9jwrfCamXacJylhEIh0ThDStsh X-Received: from apusaka-p920.tpe.corp.google.com ([2401:fa00:1:b:fdf3:9f7d:e4e3:ccad]) (user=apusaka job=sendgmr) by 2002:a62:e708:0:b029:1f8:c092:ff93 with SMTP id s8-20020a62e7080000b02901f8c092ff93mr3763813pfh.21.1616488345892; Tue, 23 Mar 2021 01:32:25 -0700 (PDT) Date: Tue, 23 Mar 2021 16:32:20 +0800 Message-Id: <20210323163141.v2.1.I6c4306f6e8ba3ccc9106067d4eb70092f8cb2a49@changeid> Mime-Version: 1.0 X-Mailer: git-send-email 2.31.0.291.g576ba9dcdaf-goog Subject: [PATCH v2] Bluetooth: check for zapped sk before connecting From: Archie Pusaka To: linux-bluetooth , Marcel Holtmann Cc: CrosBT Upstreaming , Archie Pusaka , syzbot+abfc0f5e668d4099af73@syzkaller.appspotmail.com, Alain Michaud , Abhishek Pandit-Subedi , Guenter Roeck , "David S. Miller" , Jakub Kicinski , Johan Hedberg , Luiz Augusto von Dentz , linux-kernel@vger.kernel.org, netdev@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@vger.kernel.org From: Archie Pusaka There is a possibility of receiving a zapped sock on l2cap_sock_connect(). This could lead to interesting crashes, one such case is tearing down an already tore l2cap_sock as is happened with this call trace: __dump_stack lib/dump_stack.c:15 [inline] dump_stack+0xc4/0x118 lib/dump_stack.c:56 register_lock_class kernel/locking/lockdep.c:792 [inline] register_lock_class+0x239/0x6f6 kernel/locking/lockdep.c:742 __lock_acquire+0x209/0x1e27 kernel/locking/lockdep.c:3105 lock_acquire+0x29c/0x2fb kernel/locking/lockdep.c:3599 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:137 [inline] _raw_spin_lock_bh+0x38/0x47 kernel/locking/spinlock.c:175 spin_lock_bh include/linux/spinlock.h:307 [inline] lock_sock_nested+0x44/0xfa net/core/sock.c:2518 l2cap_sock_teardown_cb+0x88/0x2fb net/bluetooth/l2cap_sock.c:1345 l2cap_chan_del+0xa3/0x383 net/bluetooth/l2cap_core.c:598 l2cap_chan_close+0x537/0x5dd net/bluetooth/l2cap_core.c:756 l2cap_chan_timeout+0x104/0x17e net/bluetooth/l2cap_core.c:429 process_one_work+0x7e3/0xcb0 kernel/workqueue.c:2064 worker_thread+0x5a5/0x773 kernel/workqueue.c:2196 kthread+0x291/0x2a6 kernel/kthread.c:211 ret_from_fork+0x4e/0x80 arch/x86/entry/entry_64.S:604 Signed-off-by: Archie Pusaka Reported-by: syzbot+abfc0f5e668d4099af73@syzkaller.appspotmail.com Reviewed-by: Alain Michaud Reviewed-by: Abhishek Pandit-Subedi Reviewed-by: Guenter Roeck --- Changes in v2: * Modify locking order for better visibility net/bluetooth/l2cap_sock.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c index f1b1edd0b697..c99d65ef13b1 100644 --- a/net/bluetooth/l2cap_sock.c +++ b/net/bluetooth/l2cap_sock.c @@ -179,9 +179,17 @@ static int l2cap_sock_connect(struct socket *sock, struct sockaddr *addr, struct l2cap_chan *chan = l2cap_pi(sk)->chan; struct sockaddr_l2 la; int len, err = 0; + bool zapped; BT_DBG("sk %p", sk); + lock_sock(sk); + zapped = sock_flag(sk, SOCK_ZAPPED); + release_sock(sk); + + if (zapped) + return -EINVAL; + if (!addr || alen < offsetofend(struct sockaddr, sa_family) || addr->sa_family != AF_BLUETOOTH) return -EINVAL;