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

serial: core: Clearing the circular buffer before NULLifying it

The circular buffer is NULLified in uart_tty_port_shutdown()
under the spin lock. However, the PM or other timer based callbacks
may still trigger after this event without knowning that buffer pointer
is not valid. Since the serial code is a bit inconsistent in checking
the buffer state (some rely on the head-tail positions, some on the
buffer pointer), it's better to have both aligned, i.e. buffer pointer
to be NULL and head-tail possitions to be the same, meaning it's empty.
This will prevent asynchronous calls to dereference NULL pointer as
reported recently in 8250 case:

BUG: kernel NULL pointer dereference, address: 00000cf5
Workqueue: pm pm_runtime_work
EIP: serial8250_tx_chars (drivers/tty/serial/8250/8250_port.c:1809)
...
? serial8250_tx_chars (drivers/tty/serial/8250/8250_port.c:1809)
__start_tx (drivers/tty/serial/8250/8250_port.c:1551)
serial8250_start_tx (drivers/tty/serial/8250/8250_port.c:1654)
serial_port_runtime_suspend (include/linux/serial_core.h:667 drivers/tty/serial/serial_port.c:63)
__rpm_callback (drivers/base/power/runtime.c:393)
? serial_port_remove (drivers/tty/serial/serial_port.c:50)
rpm_suspend (drivers/base/power/runtime.c:447)

The proposed change will prevent ->start_tx() to be called during
suspend on shut down port.
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Mon, 23 Dec 2024 20:15:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
Weaknesses CWE-476
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.9:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.9:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.9:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.9:rc4:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel

Thu, 19 Dec 2024 09:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-05-04T12:55:19.522Z

Reserved: 2024-02-19T14:20:24.206Z

Link: CVE-2024-26998

cve-icon Vulnrichment

Updated: 2024-08-02T00:21:05.918Z

cve-icon NVD

Status : Analyzed

Published: 2024-05-01T06:15:17.780

Modified: 2024-12-23T19:50:05.873

Link: CVE-2024-26998

cve-icon Redhat

Severity : Moderate

Publid Date: 2024-05-01T00:00:00Z

Links: CVE-2024-26998 - Bugzilla

cve-icon OpenCVE Enrichment

No data.