linux-kernel - [PATCH] usb: gadget: u_serial: Add null pointer check in gserial

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <1675864487-18620-1-git-send-email-quic_prashk@quicinc.com>
Date:   Wed, 8 Feb 2023 19:24:47 +0530
From:   Prashanth K <quic_prashk@...cinc.com>
To:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Christophe JAILLET <christophe.jaillet@...adoo.fr>,
        Xiu Jianfeng <xiujianfeng@...wei.com>
CC:     Pratham Pratap <quic_ppratap@...cinc.com>,
        Jack Pham <quic_jackp@...cinc.com>,
        <linux-usb@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
        Prashanth K <quic_prashk@...cinc.com>
Subject: [PATCH] usb: gadget: u_serial: Add null pointer check in gserial_resume

Consider a case where gserial_disconnect has already cleared
gser->ioport. And if a wakeup interrupt triggers afterwards,
gserial_resume gets called, which will lead to accessing of
gserial->port and thus causing null pointer dereference.Add
a null pointer check to prevent this.

Fixes: aba3a8d01d62 (" usb: gadget: u_serial: add suspend resume callbacks")
Signed-off-by: Prashanth K <quic_prashk@...cinc.com>
---
 drivers/usb/gadget/function/u_serial.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c
index 840626e..98be2b8 100644
--- a/drivers/usb/gadget/function/u_serial.c
+++ b/drivers/usb/gadget/function/u_serial.c
@@ -1428,6 +1428,9 @@ void gserial_resume(struct gserial *gser)
 	struct gs_port *port = gser->ioport;
 	unsigned long	flags;
 
+	if (!port)
+		return;
+
 	spin_lock_irqsave(&port->port_lock, flags);
 	port->suspended = false;
 	if (!port->start_delayed) {
-- 
2.7.4