From patchwork Mon Mar 22 06:01:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Archie Pusaka X-Patchwork-Id: 407532 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, URIBL_BLOCKED, USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=unavailable 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 40261C433E3 for ; Mon, 22 Mar 2021 06:02:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1B6C161966 for ; Mon, 22 Mar 2021 06:02:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229482AbhCVGB3 (ORCPT ); Mon, 22 Mar 2021 02:01:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52350 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229696AbhCVGBJ (ORCPT ); Mon, 22 Mar 2021 02:01:09 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5B4EEC061756 for ; Sun, 21 Mar 2021 23:01:09 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id u128so410378ybf.12 for ; Sun, 21 Mar 2021 23:01:09 -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=5I10KmTF85pJvFc7zWF/I23hQrUb++spC+kPfoWl0gs=; b=c9XgGsl1zbqM2sva4joEfnSV7hDID7Lv3Hg9YmulQCxI46Pp32uMd+U93tz6FJcf9V +dwPmAPherZPRSAPkRCBzDzYIYIu97H2V97Ttm5U4NWXfsUKtdsqFJgWVIBzAKCUcZTo xBMxTdBDP8/4T09zUqXjktns3k7pmDbDTMghuXfiRMsHXCnRMIc5kq+Bnxn7Ul/uGbnv hqMrlrHpY9fr05VsFp4rrpRL8GLQTfhnP46jRWB41y34YhEDaK+TR11g+1WarhhgRnyD qk5I0dc+ciajtCCqUhXOrWwj58BMGhjxEO/UP5ll3cEIE0XQczrU2+2Cqbk5kI2RBzx1 k2Kw== 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=5I10KmTF85pJvFc7zWF/I23hQrUb++spC+kPfoWl0gs=; b=c8prjcyk+oO0hSo270csFTe/cFA09t1Lgi3j91A8FA5Q0c5hxxqq5Z/CKcJXmEcoHc ZP88iZhsVn8OFajr1t7QIpzee4tc4VYLQFFwalfLYr/hMGfclHLZyMlZQ1M4+ly/4LIc OlNdzGLmj1T4S0lMUunyTU1wAEl1zLa+/SjoZwPzRantMT51iyh6ZEXF+ZdumLskdUb+ FZAoMEoTyI1qLQNTjwYONzyamyadyCN9AXYOaM8LlGhIJrut8UYx9XnmheBntWhnGk7k PxfJnOaZwymBK6eLcrOC7AxgC0I4iCV11BwSauSrx3OagYLPVoL48TMb7BRWjPDTjThS c/xg== X-Gm-Message-State: AOAM530x8XONQ+B6v67nOkKiKxcdiRWRCi7gqCeT3nRoy89sT+NXU3kC wclUoEIVvYRKdN2Kb42FF4wr+S0gt7/+ X-Google-Smtp-Source: ABdhPJyOUjg2iuItG5KmaZ6zQLnZF+LuuNxppSFBsY6NFp8yarG7SYRJ+2b6G2g8e7XiyXxlGLdY8F2+ucC9 X-Received: from apusaka-p920.tpe.corp.google.com ([2401:fa00:1:b:fdf3:9f7d:e4e3:ccad]) (user=apusaka job=sendgmr) by 2002:a25:390:: with SMTP id 138mr21736645ybd.130.1616392868490; Sun, 21 Mar 2021 23:01:08 -0700 (PDT) Date: Mon, 22 Mar 2021 14:01:01 +0800 Message-Id: <20210322140046.1.I6c4306f6e8ba3ccc9106067d4eb70092f8cb2a49@changeid> Mime-Version: 1.0 X-Mailer: git-send-email 2.31.0.rc2.261.g7f71774620-goog Subject: [PATCH] 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: netdev@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 --- net/bluetooth/l2cap_sock.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c index f1b1edd0b697..b86fd8cc4dc1 100644 --- a/net/bluetooth/l2cap_sock.c +++ b/net/bluetooth/l2cap_sock.c @@ -182,6 +182,13 @@ static int l2cap_sock_connect(struct socket *sock, struct sockaddr *addr, BT_DBG("sk %p", sk); + lock_sock(sk); + if (sock_flag(sk, SOCK_ZAPPED)) { + release_sock(sk); + return -EINVAL; + } + release_sock(sk); + if (!addr || alen < offsetofend(struct sockaddr, sa_family) || addr->sa_family != AF_BLUETOOTH) return -EINVAL;