Resource Exhaustion Affecting kernel-modules-core package, versions *


Severity

Recommended
low

Based on Red Hat Enterprise Linux security rating.

Threat Intelligence

EPSS
0.04% (12th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications

Snyk Learn

Learn about Resource Exhaustion vulnerabilities in an interactive lesson.

Start learning
  • Snyk IDSNYK-RHEL9-KERNELMODULESCORE-7121134
  • published27 May 2024
  • disclosed24 May 2024

Introduced: 24 May 2024

CVE-2021-47527  (opens in a new tab)
CWE-400  (opens in a new tab)

How to fix?

There is no fixed version for RHEL:9 kernel-modules-core.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-modules-core package and not the kernel-modules-core package as distributed by RHEL. See How to fix? for RHEL:9 relevant fixed versions and status.

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

serial: core: fix transmit-buffer reset and memleak

Commit 761ed4a94582 ("tty: serial_core: convert uart_close to use tty_port_close") converted serial core to use tty_port_close() but failed to notice that the transmit buffer still needs to be freed on final close.

Not freeing the transmit buffer means that the buffer is no longer cleared on next open so that any ioctl() waiting for the buffer to drain might wait indefinitely (e.g. on termios changes) or that stale data can end up being transmitted in case tx is restarted.

Furthermore, the buffer of any port that has been opened would leak on driver unbind.

Note that the port lock is held when clearing the buffer pointer due to the ldisc race worked around by commit a5ba1d95e46e ("uart: fix race between uart_put_char() and uart_shutdown()").

Also note that the tty-port shutdown() callback is not called for console ports so it is not strictly necessary to free the buffer page after releasing the lock (cf. d72402145ace ("tty/serial: do not free trasnmit buffer page under port lock")).

CVSS Scores

version 3.1