From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail115-171.sinamail.sina.com.cn (mail115-171.sinamail.sina.com.cn [218.30.115.171]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 484406FBE for ; Thu, 28 Dec 2023 11:39:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sina.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sina.com X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([116.24.9.182]) by sina.com (172.16.235.25) with ESMTP id 658D5DE200004E96; Thu, 28 Dec 2023 19:37:10 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com Authentication-Results: sina.com; spf=none smtp.mailfrom=hdanton@sina.com; dkim=none header.i=none; dmarc=none action=none header.from=hdanton@sina.com X-SMAIL-MID: 17714734210344 X-SMAIL-UIID: 417FC9C255D24E9990460A3C094297CE-20231228-193710-1 From: Hillf Danton To: syzbot Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [bluetooth?] WARNING in l2cap_do_send (2) Date: Thu, 28 Dec 2023 19:36:57 +0800 Message-Id: <20231228113657.1673-1-hdanton@sina.com> In-Reply-To: <00000000000081a088060d7190cb@google.com> References: <00000000000081a088060d7190cb@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Tue, 26 Dec 2023 14:54:27 -0800 > HEAD commit: fbafc3e621c3 Merge tag 'for_linus' of git://git.kernel.org.. > git tree: upstream > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14125c81e80000 #syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master --- x/net/bluetooth/hci_core.c +++ y/net/bluetooth/hci_core.c @@ -3235,9 +3235,12 @@ void hci_send_acl(struct hci_chan *chan, BT_DBG("%s chan %p flags 0x%4.4x", hdev->name, chan, flags); + if (!mutex_trylock(&hdev->req_lock)) + return; hci_queue_acl(chan, &chan->data_q, skb, flags); queue_work(hdev->workqueue, &hdev->tx_work); + mutex_unlock(&hdev->req_lock); } /* Send SCO data */ --