PT-2026-43835 · Linux · Linux

Published 2026-05-27 · Updated 2026-05-27 · CVE-2026-45968

Mitre

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

cpuidle: Skip governor when only one idle state is available

On certain platforms (PowerNV systems without a power-mgt DT node), cpuidle may register only a single idle state. In cases where that single state is a polling state (state 0), the ladder governor may incorrectly treat state 1 as the first usable state and pass an out-of-bounds index. This can lead to a NULL enter callback being invoked, ultimately resulting in a system crash.

[ 13.342636] cpuidle-powernv : Only Snooze is available [ 13.351854] Faulting instruction address: 0x00000000 [ 13.376489] NIP [0000000000000000] 0x0 [ 13.378351] LR [c000000001e01974] cpuidle enter state+0x2c4/0x668

Fix this by adding a bail-out in cpuidle select() that returns state 0 directly when state count <= 1, bypassing the governor and keeping the tick running.

Related Identifiers

CVE-2026-45968

Affected Products

Linux

References · 9

• https://nvd.nist.gov/vuln/detail/CVE-2026-45968 · Security Note
• https://git.kernel.org/stable/c/e5c9ffc6ae1bcdb1062527d611043681ac301aca · Note
• https://git.kernel.org/stable/c/a0f7e804edc82e513d1ccb7c95ed8b351522ec81 · Note
• https://git.kernel.org/stable/c/a0724e40a58a0e323c59707edeae5b71d15800dc · Note
• https://git.kernel.org/stable/c/5d103a38e2ae96eca57fd17161bcd29bd4622d1c · Note
• https://git.kernel.org/stable/c/63ae78336f40bcd9a44952a7c6bafb9c88a8effd · Note
• https://git.kernel.org/stable/c/8f6833d919bae915ead6c599a53e81e19b32da52 · Note
• https://git.kernel.org/stable/c/5c577ac939bca486cb02069505cfe47a5312ce02 · Note
• https://git.kernel.org/stable/c/4da2b897283c39980d6ae09dc1560fcd937879e5 · Note