CVE-2024-46706

MEDIUMCVSS 5.5/10EPSS 0.21%

Last modified

CVE-2024-46706 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. In the Linux kernel, the following vulnerability has been resolved: tty: serial: fsl_lpuart: mark last busy before uart_add_one_port With "earlycon initcall_debug=1 loglevel=8" in bootargs, kernel sometimes boot hang. It is because normal console still is not ready, but runtime suspend is called, so early console putchar will hang in waiting TRDE set in UARTSTAT. The lpuart driver has auto suspend delay set to 3000ms, but during uart_add_one_port, a child device serial ctrl will added and probed with its pm runtime enabled(see serial_ctrl.c). The runtime suspend call path is: device_add |-> bus_probe_device |->device_initial_probe |->__device_attach |-> pm_runtime_get_sync(dev->parent); |-> pm_request_idle(dev); |-> pm_runtime_put(dev->parent); So in the end, before normal console ready, the lpuart get runtime suspended. EPSS estimates a 0.21% chance of exploitation in the next 30 days.

Description

In the Linux kernel, the following vulnerability has been resolved: tty: serial: fsl_lpuart: mark last busy before uart_add_one_port With "earlycon initcall_debug=1 loglevel=8" in bootargs, kernel sometimes boot hang. It is because normal console still is not ready, but runtime suspend is called, so early console putchar will hang in waiting TRDE set in UARTSTAT. The lpuart driver has auto suspend delay set to 3000ms, but during uart_add_one_port, a child device serial ctrl will added and probed with its pm runtime enabled(see serial_ctrl.c). The runtime suspend call path is: device_add |-> bus_probe_device |->device_initial_probe |->__device_attach |-> pm_runtime_get_sync(dev->parent); |-> pm_request_idle(dev); |-> pm_runtime_put(dev->parent); So in the end, before normal console ready, the lpuart get runtime suspended. And earlycon putchar will hang. To address the issue, mark last busy just after pm_runtime_enable, three seconds is long enough to switch from bootconsole to normal console.

Metrics

CVSS 3.1
5.5/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Probability
0.21%

11.9th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

VendorProductVersionsUpdate
LinuxLinux Kernel>= 6.2, < 6.6.48
LinuxLinux Kernel>= 6.7, < 6.10.7
LinuxLinux Kernel6.11Rc1

References

Timeline

Published
Last Modified
Status
Analyzed

Frequently Asked Questions

What is CVE-2024-46706?
In the Linux kernel, the following vulnerability has been resolved: tty: serial: fsl_lpuart: mark last busy before uart_add_one_port With "earlycon initcall_debug=1 loglevel=8" in bootargs, kernel sometimes boot hang. It is because normal console still is not ready, but runtime suspend is called, so early console putchar will hang in waiting TRDE set in UARTSTAT. The lpuart driver has auto suspend delay set to 3000ms, but during uart_add_one_port, a child device serial ctrl will added and probed with its pm runtime enabled(see serial_ctrl.c). The runtime suspend call path is: device_add |-> bus_probe_device |->device_initial_probe |->__device_attach |-> pm_runtime_get_sync(dev->parent); |-> pm_request_idle(dev); |-> pm_runtime_put(dev->parent); So in the end, before normal console ready, the lpuart get runtime suspended. And earlycon putchar will hang. To address the issue, mark last busy just after pm_runtime_enable, three seconds is long enough to switch from bootconsole to normal console.
How severe is CVE-2024-46706?
CVE-2024-46706 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.21% probability of exploitation in the next 30 days.
How do I fix CVE-2024-46706?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2024-46706?

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Source: NVD / NIST