From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f69.google.com (mail-oo1-f69.google.com [209.85.161.69]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 78BF72147F9 for ; Tue, 19 May 2026 15:35:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.69 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779204937; cv=none; b=EUR32Frz/y3vwNryYlD3L5LHlrn7H0mS+z0p5EzbEq5IjScnivilCOQ+YhiGvb2UoU0gGnDDlDI/qq47gquw7uE+Qp+YKgHRkEkHyUmjlXm7zHuE6X8asq+m9tf3+FKJuREGQJ6WqHCepAH3TR3/Ot5T9XEn2lGow5/lKhRu+sM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779204937; c=relaxed/simple; bh=or4Cv9FLOHZa4tM32008z6hkYOFCsIfZdexRZZoR8aw=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To:Cc: Content-Type; b=U70Xe5b2OlB9zeh4qJZY1bI2ZSKg0OLOy4uESCGSpx2xAKsCBLzj4VqggNeFV6onoNSMqE1ocj0bUcxmHXzAuGFp4wcDtsQHcmEcqZaq2LhetJwzzKLPQg3NQOXczESrtFa2pNFQ6rHFcV88yHRK1qlgyVtNVVpnMrEkF+/s8QA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.161.69 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oo1-f69.google.com with SMTP id 006d021491bc7-6967b799acdso8424121eaf.3 for ; Tue, 19 May 2026 08:35:35 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779204934; x=1779809734; h=cc:to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=oLCR5XLoY6hcY0n1ccHtBEEtlt9GM/Sbv34omm6Z38g=; b=czjXsKjpVVpa+jQJJH1v8kTtDv9SlWEZMgyv7DQegeESSNAOR5MkIMc5Ln9W3vTTTo PnJuS/9S2AZWqqKoiFogaMFxcAs9A66IQmIZrQ10VKP9c5M8ixadHHdEa5ZwI7TAiuZV hT0lfveSdQzuvWQx4IXt1ThgskfGF36rq/KBMJO1G3WdjpWHHGuPJKMIpsmG7b6lzSCy mdDRKMwMAYsH2R7X4sqLXdu3yqhOjKzQr0OSU3yOGHHTXoUe69UsEnhIdCxBhIhd0HGh 5c+Ui5ooj/BoHD1QSP8DpR+bKwlNTIEcLRoFpE0j1vBBXY/rbBCq6d1CmWKL7pqIPACs qUBg== X-Forwarded-Encrypted: i=1; AFNElJ/uat0qg2XfP2+unbCOLFT4lHSZYuIvuLr2f95Qg3aauTehVdbeasYsbULgsJvt59XYEBWUeHTcvLbmAGY=@vger.kernel.org X-Gm-Message-State: AOJu0YyBsh4lPK81rzDOvunjFLJrGexVZ/PT+P2p1QK8kV8Ml8q3FQy8 NrkhwPrvKEIoTNjtvdWD6YHVT9wBrhfsZMZmzct2XAbC/+ivuySJVfQ+yUEz4TZLPXy6nN3/zxn zTXDrq8Z2IRDhqSoFjdyiA9yh0VbEp82MfyH95XeszCCjPFHkYgGg1VkcuhQ= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:2206:b0:696:637e:4831 with SMTP id 006d021491bc7-69c94315b9emr11831543eaf.25.1779204934520; Tue, 19 May 2026 08:35:34 -0700 (PDT) Date: Tue, 19 May 2026 08:35:34 -0700 In-Reply-To: <20260519153500.12948-1-kernel@phwe.de> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a0c8346.170a0220.39a13.0004.GAE@google.com> Subject: Re: [syzbot] [bluetooth?] [usb?] KASAN: slab-use-after-free Read in skb_dequeue (2) From: syzbot To: kernel@phwe.de Cc: kernel@phwe.de, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" > #syz test This crash does not have a reproducer. I cannot test it. > > Drain rx_work in btusb_disconnect() before kfree(data) so that any > work item rescheduled by a late URB completion callback during > btusb_close() is waited for before the backing data is freed. > > --- > drivers/bluetooth/btusb.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c > index 7f5fce93d984..5d4ea44cd3c9 100644 > --- a/drivers/bluetooth/btusb.c > +++ b/drivers/bluetooth/btusb.c > @@ -4462,6 +4462,15 @@ static void btusb_disconnect(struct usb_interface *intf) > usb_driver_release_interface(&btusb_driver, data->intf); > } > > + /* > + * rx_work is scheduled from URB completion handlers; btusb_close() > + * (called via hci_unregister_dev) uses a non-sync cancel, so a work > + * item may still be queued or executing when we reach this point. > + * Wait for it before freeing data, otherwise the worker dereferences > + * freed memory through skb_dequeue(&data->acl_q). > + */ > + cancel_delayed_work_sync(&data->rx_work); > + > hci_free_dev(hdev); > kfree(data); > } > -- > 2.53.0 >