Upstream information
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.
SUSE information
Overall state of this security issue: Does not affect SUSE products
SUSE Bugzilla entry: 1263917 [NEW] No SUSE Security Announcements cross referenced.SUSE Timeline for this CVE
CVE page created: Mon May 4 17:21:50 2026CVE page last modified: Mon May 4 17:21:50 2026