From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f69.google.com (mail-ot1-f69.google.com [209.85.210.69]) (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 AB120492522 for ; Wed, 9 Sep 2026 12:33:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.69 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788957224; cv=none; b=p0bWt/TpN0OxdlpvxKPdnMNLgTFaBpsWIhUQLQBwwGYo9n5GmTFfh/im0kzZWSnSlcvKd/JiVNpyQCKQd+Q9U0lkrblhS1V8wZiwRjuJBfA8W3Nlah/m5ubWBzg8SgVLts1Ac7CQnGXtpBRMBUp9ctwsc1tkDiSf6vuG8z7vtx4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788957224; c=relaxed/simple; bh=KS1N6k2YLTMDi7c0RGLz/xl9wUEpOP5ZMfi9x4dtylU=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=Skz6wPtP/+LmljvweVU2w1eSlRJSDR85t/w/eQl0nAsOY1R12rm7kPcE5HXU5ePIAIOMbVYQ1MaxHRAdEoB/Kyu/ABHybp0s3OWDd7zY+F/NEugi88yaEape/HijFvZgUs/0M90AkhOOEb5a00NxgnQfrr+f0DP9Nf47YPyhZbI= 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=209.85.210.69 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-ot1-f69.google.com with SMTP id 46e09a7af769-7ec6685adabso8164678a34.0 for ; Wed, 09 Sep 2026 05:33:42 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1788957221; x=1789562021; h=content-type:to:from:subject:message-id:in-reply-to:date :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to:content-type; bh=Lcl1dgouCFGOLM4r5ViGc8pC9IXATr1+8cPCCR6EmR0=; b=J+hZNy/95II+6bKoEQl329yICr9vkR28nWIZi0wf0WUIT3raM6giLRcZwGemQKDK+B 93r2ZUQmzMafSpkUf0myJTfBRnyXWmcxmoSXPhuaraPP/6otoUUqEukD9WP5yJbGd1Tf +jT9rulikob2L68qWB4fFCfyCmDK0Z9jRtqkIR3ZnZUjMjiGeOKRwQRzLgWnO8XwrfR6 diDyCDH405qzA154A1AuWFYyqllgUsTAV38jZinyuCYMfRdfbB7dsyYXCRvIYRrHKlaW WPX1zAXDsOP0c43tqncppZtFa2YNWqg5hLoOdt/mWJXVQuUrLjKmHzS5mljnYskv7hXH MEKw== X-Gm-Message-State: AFuF++nwHDCIutP6niZWJav0T3B9HakaCbdnl2+Y8t/NC1aijy0JFKaL s5YXZXYzqYmOjIU6vlttf0gdAnyPkbsN+ItN7KeqIzD0aHaLJPKftGDnc5fTwhVqBlSV9tseTP9 DsLlsxgJ8gXBAxbokbX5g66bJcETv29RDjbepeyUrsCrm4JZQ5aPvH9KC35k= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:8596:10b0:6b7:8415:d799 with SMTP id 006d021491bc7-6b78415d91emr12758841eaf.68.1788957221494; Wed, 09 Sep 2026 05:33:41 -0700 (PDT) Date: Wed, 09 Sep 2026 05:33:41 -0700 In-Reply-To: <6a6d375e.2d659fcc.1d46f5.01a4.GAE@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6aa15225.6e6c5f9e.28f11f.0027.GAE@google.com> Subject: Forwarded: Re: test patch From: syzbot To: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" For archival purposes, forwarding an incoming command email to linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com. *** Subject: Re: test patch Author: syedtayyabfarooq08@gmail.com #syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c index cdd1dfc666c4..5974a9303ecf 100644 --- a/drivers/usb/gadget/function/u_serial.c +++ b/drivers/usb/gadget/function/u_serial.c @@ -603,6 +603,41 @@ static int gserial_wakeup_host(struct gserial *gser) /* TTY Driver */ +static int gs_install(struct tty_driver *driver, struct tty_struct *tty) +{ + struct gs_port *port; + struct tty_port *tport; + int ret; + + mutex_lock(&ports[tty->index].lock); + port = ports[tty->index].port; + if (!port) { + mutex_unlock(&ports[tty->index].lock); + return -ENODEV; + } + + tport = tty_port_get(&port->port); + mutex_unlock(&ports[tty->index].lock); + + if (!tport) + return -ENODEV; + + ret = tty_port_install(tport, driver, tty); + if (ret) { + tty_port_put(tport); + return ret; + } + + tty->driver_data = port; + + return 0; +} + +static void gs_cleanup(struct tty_struct *tty) +{ + tty_port_put(tty->port); +} + /* * gs_open sets up the link between a gs_port and its associated TTY. * That link is broken *only* by TTY close(), and all driver methods @@ -695,14 +730,16 @@ static void gs_close(struct tty_struct *tty, struct file *file) struct gs_port *port = tty->driver_data; struct gserial *gser; + if (!port) + return; + spin_lock_irq(&port->port_lock); if (port->port.count != 1) { raced_with_open: - if (port->port.count == 0) - WARN_ON(1); - else + if (port->port.count > 0) --port->port.count; + goto exit; } @@ -911,6 +948,8 @@ static int gs_get_icount(struct tty_struct *tty, static const struct tty_operations gs_tty_ops = { .open = gs_open, .close = gs_close, + .install = gs_install, + .cleanup = gs_cleanup, .write = gs_write, .put_char = gs_put_char, .flush_chars = gs_flush_chars, @@ -1203,6 +1242,18 @@ static void gs_console_exit(struct gs_port *port) #endif +static void gs_port_destruct(struct tty_port *tport) +{ + struct gs_port *port = container_of(tport, struct gs_port, port); + + kfree(port); +} + +static const struct tty_port_operations gs_port_ops = { + .destruct = gs_port_destruct, +}; + + static int gs_port_alloc(unsigned port_num, struct usb_cdc_line_coding *coding) { @@ -1222,6 +1273,7 @@ gs_port_alloc(unsigned port_num, struct usb_cdc_line_coding *coding) } tty_port_init(&port->port); + port->port.ops = &gs_port_ops; spin_lock_init(&port->port_lock); init_waitqueue_head(&port->drain_wait); init_waitqueue_head(&port->close_wait); @@ -1258,8 +1310,7 @@ static void gserial_free_port(struct gs_port *port) /* wait for old opens to finish */ wait_event(port->close_wait, gs_closed(port)); WARN_ON(port->port_usb != NULL); - tty_port_destroy(&port->port); - kfree(port); + tty_port_put(&port->port); } void gserial_free_line(unsigned char port_num)