Improper control of a resource through its lifetime in Linux kernel - CVE-2026-74654

Vulnerability details

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper state management in serial8250_rx_dma_flush() and serial8250_release_dma() when reopening a port after it is closed during an active RX DMA transfer. A local user can close and reopen the serial port to trigger a kernel Oops and cause a denial of service.

The issue occurs because stale RX state can remain set while the RX DMA channel is unavailable.

Affected software

How to mitigate CVE-2026-74654

External References

• https://git.kernel.org/stable/c/9f2444f4c0e4b06f61bae38da87c9c94c78efa86
• https://git.kernel.org/stable/c/ae05d9e50b6b9f246c110b3bdc03676145c2d0d4
• https://git.kernel.org/stable/c/bf4fb620e02962b2b52500a4b3d8420f351eb46a
• https://git.kernel.org/stable/c/d06cfb1add4a2d5b393e9e31f49ebbd168beea49
• https://git.kernel.org/stable/c/e10f06ee050a08930e2339b6fec7148fd0b2a8f6
• https://git.kernel.org/stable/c/e2fe6a0efecbef00e3ecc2db64dd5afa8c212b41
• https://git.kernel.org/stable/c/e7a5d792cf64a2096e18f1d573cc3d01cba15e92
• https://git.kernel.org/stable/c/e7e3cc6709caa49d1d6ce6c1f7cb305e38675cc9

Related Security Bulletins

• Improper control of a resource through its lifetime in Linux kernel serial 8250 driver
• Debian update for linux