In the Linux kernel, the following vulnerability has been resolved: usb: atm: cxacru: fix endpoint checking in cxacru_bind() Syzbot is still reporting quite an old issue [1] that occurs due to incomplete checking of present usb endpoints. As such, wrong endpoints types may be used at urb sumbitting stage which in turn triggers a warning in usb_submit_urb(). Fix the issue by verifying that required endpoint types are present for both in and out endpoints, taking into account cmd endpoint type. Unfortunately, this patch has not been tested on real hardware. [1] Syzbot report: usb 1-1: BOGUS urb xfer, pipe 1 != type 3 WARNING: CPU: 0 PID: 8667 at drivers/usb/core/urb.c:502 usb_submit_urb+0xed2/0x18a0 drivers/usb/core/urb.c:502 Modules linked in: CPU: 0 PID: 8667 Comm: kworker/0:4 Not tainted 5.14.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event RIP: 0010:usb_submit_urb+0xed2/0x18a0 drivers/usb/core/urb.c:502 ... Call Trace: cxacru_cm+0x3c0/0x8e0 drivers/usb/atm/cxacru.c:649 cxacru_card_status+0x22/0xd0 drivers/usb/atm/cxacru.c:760 cxacru_bind+0x7ac/0x11a0 drivers/usb/atm/cxacru.c:1209 usbatm_usb_probe+0x321/0x1ae0 drivers/usb/atm/usbatm.c:1055 cxacru_usb_probe+0xdf/0x1e0 drivers/usb/atm/cxacru.c:1363 usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:517 [inline] really_probe+0x23c/0xcd0 drivers/base/dd.c:595 __driver_probe_device+0x338/0x4d0 drivers/base/dd.c:747 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:777 __device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:894 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427 __device_attach+0x228/0x4a0 drivers/base/dd.c:965 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487 device_add+0xc2f/0x2180 drivers/base/core.c:3354 usb_set_configuration+0x113a/0x1910 drivers/usb/core/message.c:2170 usb_generic_driver_probe+0xba/0x100 drivers/usb/core/generic.c:238 usb_probe_device+0xd9/0x2c0 drivers/usb/core/driver.c:293
| Métrique | Valeur | Interprétation |
|---|---|---|
|
AV (Vecteur d'Attaque)
Attack Vector
|
Local (L)
|
Exploit nécessite un accès local au système |
|
AC (Complexité d'Attaque)
Attack Complexity
|
Low (L)
|
Peu de conditions requises pour exploiter |
|
PR (Privilèges Requis)
Privileges Required
|
Low (L)
|
Authentifié avec compte utilisateur basique |
|
UI (Interaction Utilisateur)
User Interaction
|
None (N)
|
Aucune interaction utilisateur nécessaire |
|
S (Périmètre)
Scope
|
Unchanged (U)
|
Impact reste dans le périmètre du composant compromis |
|
C (Impact Confidentialité)
Confidentiality Impact
|
None (N)
|
Aucune divulgation d'informations |
|
I (Impact Intégrité)
Integrity Impact
|
None (N)
|
Aucune modification de données possible |
|
A (Impact Disponibilité)
Availability Impact
|
High (H)
|
Interruption totale du service possible |
usb: atm: cxacru: fix endpoint checking in cxacru_bind()