Patch "usb: dwc3: gadget: Fix NULL pointer dereference in dwc3_gadget_suspend" has been added to the 6.1-stable tree

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



This is a note to let you know that I've just added the patch titled

    usb: dwc3: gadget: Fix NULL pointer dereference in dwc3_gadget_suspend

to the 6.1-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     usb-dwc3-gadget-fix-null-pointer-dereference-in-dwc3_gadget_suspend.patch
and it can be found in the queue-6.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.


>From 61a348857e869432e6a920ad8ea9132e8d44c316 Mon Sep 17 00:00:00 2001
From: Uttkarsh Aggarwal <quic_uaggarwa@xxxxxxxxxxx>
Date: Fri, 19 Jan 2024 15:18:25 +0530
Subject: usb: dwc3: gadget: Fix NULL pointer dereference in dwc3_gadget_suspend

From: Uttkarsh Aggarwal <quic_uaggarwa@xxxxxxxxxxx>

commit 61a348857e869432e6a920ad8ea9132e8d44c316 upstream.

In current scenario if Plug-out and Plug-In performed continuously
there could be a chance while checking for dwc->gadget_driver in
dwc3_gadget_suspend, a NULL pointer dereference may occur.

Call Stack:

	CPU1:                           CPU2:
	gadget_unbind_driver            dwc3_suspend_common
	dwc3_gadget_stop                dwc3_gadget_suspend
                                        dwc3_disconnect_gadget

CPU1 basically clears the variable and CPU2 checks the variable.
Consider CPU1 is running and right before gadget_driver is cleared
and in parallel CPU2 executes dwc3_gadget_suspend where it finds
dwc->gadget_driver which is not NULL and resumes execution and then
CPU1 completes execution. CPU2 executes dwc3_disconnect_gadget where
it checks dwc->gadget_driver is already NULL because of which the
NULL pointer deference occur.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 9772b47a4c29 ("usb: dwc3: gadget: Fix suspend/resume during device mode")
Acked-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>
Signed-off-by: Uttkarsh Aggarwal <quic_uaggarwa@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240119094825.26530-1-quic_uaggarwa@xxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/usb/dwc3/gadget.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -4583,15 +4583,13 @@ int dwc3_gadget_suspend(struct dwc3 *dwc
 	unsigned long flags;
 	int ret;
 
-	if (!dwc->gadget_driver)
-		return 0;
-
 	ret = dwc3_gadget_soft_disconnect(dwc);
 	if (ret)
 		goto err;
 
 	spin_lock_irqsave(&dwc->lock, flags);
-	dwc3_disconnect_gadget(dwc);
+	if (dwc->gadget_driver)
+		dwc3_disconnect_gadget(dwc);
 	spin_unlock_irqrestore(&dwc->lock, flags);
 
 	return 0;


Patches currently in stable-queue which might be from quic_uaggarwa@xxxxxxxxxxx are

queue-6.1/usb-dwc3-gadget-fix-null-pointer-dereference-in-dwc3_gadget_suspend.patch




[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux