7.8

CVE-2022-49980

In the Linux kernel, the following vulnerability has been resolved:

USB: gadget: Fix use-after-free Read in usb_udc_uevent()

The syzbot fuzzer found a race between uevent callbacks and gadget
driver unregistration that can cause a use-after-free bug:

---------------------------------------------------------------
BUG: KASAN: use-after-free in usb_udc_uevent+0x11f/0x130
drivers/usb/gadget/udc/core.c:1732
Read of size 8 at addr ffff888078ce2050 by task udevd/2968

CPU: 1 PID: 2968 Comm: udevd Not tainted 5.19.0-rc4-next-20220628-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google
06/29/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:317 [inline]
 print_report.cold+0x2ba/0x719 mm/kasan/report.c:433
 kasan_report+0xbe/0x1f0 mm/kasan/report.c:495
 usb_udc_uevent+0x11f/0x130 drivers/usb/gadget/udc/core.c:1732
 dev_uevent+0x290/0x770 drivers/base/core.c:2424
---------------------------------------------------------------

The bug occurs because usb_udc_uevent() dereferences udc->driver but
does so without acquiring the udc_lock mutex, which protects this
field.  If the gadget driver is unbound from the udc concurrently with
uevent processing, the driver structure may be accessed after it has
been deallocated.

To prevent the race, we make sure that the routine holds the mutex
around the racing accesses.
Verknüpft mit AI von unstrukturierten Daten zu bestehenden CPE der NVD
Diese Information steht angemeldeten Benutzern zur Verfügung. Login Login
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Linux ≫ Linux Kernel Version < 5.19.7
Zu dieser CVE wurde keine CISA KEV oder CERT.AT-Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.02% 0.034
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
nvd@nist.gov 7.8 1.8 5.9
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE-416 Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.