Bug 2327177 (CVE-2024-50269)

Summary: CVE-2024-50269 kernel: usb: musb: sunxi: Fix accessing an released usb phy
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: dfreiber, drow, jburrell, vkumar
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 2327243    
Bug Blocks:    

Description OSIDB Bzimport 2024-11-19 02:01:59 UTC
In the Linux kernel, the following vulnerability has been resolved:

usb: musb: sunxi: Fix accessing an released usb phy

Commit 6ed05c68cbca ("usb: musb: sunxi: Explicitly release USB PHY on
exit") will cause that usb phy @glue->xceiv is accessed after released.

1) register platform driver @sunxi_musb_driver
// get the usb phy @glue->xceiv
sunxi_musb_probe() -> devm_usb_get_phy().

2) register and unregister platform driver @musb_driver
musb_probe() -> sunxi_musb_init()
use the phy here
//the phy is released here
musb_remove() -> sunxi_musb_exit() -> devm_usb_put_phy()

3) register @musb_driver again
musb_probe() -> sunxi_musb_init()
use the phy here but the phy has been released at 2).
...

Fixed by reverting the commit, namely, removing devm_usb_put_phy()
from sunxi_musb_exit().

Comment 1 Avinash Hanwate 2024-11-19 05:40:23 UTC
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2024111926-CVE-2024-50269-830b@gregkh/T