CVEvulnerability
CVE-2026-31741
5.5 MEDIUM
Official page ↗
- Status
- Analyzed
- Published
- 2026-05-01
- Last modified
- 2026-06-17
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 ([email protected])
- 5.5 MEDIUM — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Description
In the Linux kernel, the following vulnerability has been resolved:
counter: rz-mtu3-cnt: prevent counter from being toggled multiple times
Runtime PM counter is incremented / decremented each time the sysfs
enable file is written to.
If user writes 0 to the sysfs enable file multiple times, runtime PM
usage count underflows, generating the following message.
rz-mtu3-counter rz-mtu3-counter.0: Runtime PM usage count underflow!
At the same time, hardware registers end up being accessed with clocks
off in rz_mtu3_terminate_counter() to disable an already disabled
channel.
If user writes 1 to the sysfs enable file multiple times, runtime PM
usage count will be incremented each time, requiring the same number of
0 writes to get it back to 0.
If user writes 0 to the sysfs enable file while PWM is in progress, PWM
is stopped without counter being the owner of the underlying MTU3
channel.
Check against the cached count_is_enabled value and exit if the user
is trying to set the same enable value.
Affected configurations
• linux linux kernel (>= 6.4 < 6.6.134)
• linux linux kernel (>= 6.7 < 6.12.81)
• linux linux kernel (>= 6.13 < 6.18.22)
• linux linux kernel (>= 6.19 < 6.19.12)
• linux linux kernel 7.0
References
- https://git.kernel.org/stable/c/67c3f99bed6f422ba343d2b70a2eeeccdfd91bef Patch
- https://git.kernel.org/stable/c/885aa739a07ab45e90dfa997205acec97979ce4e Patch
- https://git.kernel.org/stable/c/ced8b48420eddb1251f93c22dc23fa136490b3cd Patch
- https://git.kernel.org/stable/c/e07237df8538b0ae98dce112e4f6db093d767f80 Patch
- https://git.kernel.org/stable/c/f5f6f06d7e6d262026578b59ba7426eb04acce5d Patch