NothingOSS/android_kernel_msm-6.1_nothing_sm7635
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

UPSTREAM: usb: gadget: u_serial: Add null pointer check in gs_start_io

Browse source 
If gs_close has cleared port->port.tty and gs_start_io is called
afterwards, then the function tty_wakeup will attempt to access the value
of the pointer port->port.tty which will cause a null pointer
dereference error.

To avoid this, add a null pointer check to gs_start_io before attempting
to access the value of the pointer port->port.tty.

Signed-off-by: Kuen-Han Tsai <khtsai@google.com>
Message-ID: <20230602070009.1353946-1-khtsai@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Bug: 283247551
(cherry picked from commit ffd603f214237e250271162a5b325c6199a65382)
Change-Id: I782ef328b0d49810d3fb23c002a86439e6728542
Signed-off-by: Kuen-Han Tsai <khtsai@google.com>
(cherry picked from commit ca0cd377615866a0253c6e495f99fad57bbaab86)
This commit is contained in:
Kuen-Han Tsai 2023-06-02 15:00:06 +08:00
parent ac9005946a
commit 2f2c035453
1 changed files with 5 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

6
drivers/usb/gadget/function/u_serial.c
View file

@ -538,16 +538,20 @@ static int gs_alloc_requests(struct usb_ep *ep, struct list_head *head,
static int gs_start_io(struct gs_port *port) static int gs_start_io(struct gs_port *port)
{ {
struct list_head *head = &port->read_pool; struct list_head *head = &port->read_pool;
struct usb_ep *ep = port->port_usb->out; struct usb_ep *ep;
int status; int status;
unsigned started; unsigned started;
if (!port->port_usb || !port->port.tty)
return -EIO;
/* Allocate RX and TX I/O buffers. We can't easily do this much /* Allocate RX and TX I/O buffers. We can't easily do this much
* earlier (with GFP_KERNEL) because the requests are coupled to * earlier (with GFP_KERNEL) because the requests are coupled to
* endpoints, as are the packet sizes we'll be using. Different * endpoints, as are the packet sizes we'll be using. Different
* configurations may use different endpoints with a given port; * configurations may use different endpoints with a given port;
* and high speed vs full speed changes packet sizes too. * and high speed vs full speed changes packet sizes too.
*/ */
ep = port->port_usb->out;
status = gs_alloc_requests(ep, head, gs_read_complete, status = gs_alloc_requests(ep, head, gs_read_complete,
&port->read_allocated); &port->read_allocated);
if (status) if (status)