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CVE-2026-31741 (GCVE-0-2026-31741)

Vulnerability from cvelistv5 – Published: 2026-05-01 14:14 – Updated: 2026-05-11 22:14
VLAI
Title
counter: rz-mtu3-cnt: prevent counter from being toggled multiple times
Summary
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.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 0be8907359df4c62319f5cb2c6981ff0d9ebf35a , < 885aa739a07ab45e90dfa997205acec97979ce4e (git)
Affected: 0be8907359df4c62319f5cb2c6981ff0d9ebf35a , < ced8b48420eddb1251f93c22dc23fa136490b3cd (git)
Affected: 0be8907359df4c62319f5cb2c6981ff0d9ebf35a , < e07237df8538b0ae98dce112e4f6db093d767f80 (git)
Affected: 0be8907359df4c62319f5cb2c6981ff0d9ebf35a , < f5f6f06d7e6d262026578b59ba7426eb04acce5d (git)
Affected: 0be8907359df4c62319f5cb2c6981ff0d9ebf35a , < 67c3f99bed6f422ba343d2b70a2eeeccdfd91bef (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.4
Unaffected: 0 , < 6.4 (semver)
Unaffected: 6.6.134 , ≤ 6.6.* (semver)
Unaffected: 6.12.81 , ≤ 6.12.* (semver)
Unaffected: 6.18.22 , ≤ 6.18.* (semver)
Unaffected: 6.19.12 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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}



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