CVE-2026-89936

Summary

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

iio: dac: m62332: Fix regulator reference count imbalance

m62332_set_value() enables the Vcc regulator on every write of a non-zero value and disables it on every write of zero, without tracking the channel's current state. Because the regulator is reference counted, changing a channel directly from one non-zero value to another enables it more than once, while a later write of zero disables it only once. The reference count never returns to zero and the regulator is left enabled indefinitely.

Only enable the regulator on the transition from zero to non-zero, and only disable it on the transition from non-zero to zero, using the previously stored channel value to detect the edge. Balance the regulator on the I2C error path so the reference count stays consistent if the write fails.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxb87b0c0f81e8d11c881b726b886b7502ab67d884 < bac0ed8bee651aa841375edf72c6ab1d10ac80c6affected
LinuxLinuxb87b0c0f81e8d11c881b726b886b7502ab67d884 < 9263b9ad968a563337a60e0eb66e35186e1faf9aaffected
LinuxLinuxb87b0c0f81e8d11c881b726b886b7502ab67d884 < 1d3a7d7dd3adee19e00be2b2237140f0fe169484affected
LinuxLinuxb87b0c0f81e8d11c881b726b886b7502ab67d884 < f5acb824277a97a5210c454872202bf7f08c75d4affected
LinuxLinuxb87b0c0f81e8d11c881b726b886b7502ab67d884 < ae18d2d2ef27a4d04fda6e30c23774513dc9be1eaffected
LinuxLinuxb87b0c0f81e8d11c881b726b886b7502ab67d884 < 08ac8d2976d57aa943d64e351c4d0bd8bb0c6de9affected
LinuxLinuxb87b0c0f81e8d11c881b726b886b7502ab67d884 < 9fe22f563b2a0fdb11fd3711a8c39c023629c08aaffected
LinuxLinuxb87b0c0f81e8d11c881b726b886b7502ab67d884 < a130404ce0b69ca1438126bd81c1985d3b4d2e6faffected
LinuxLinux4.2affected
LinuxLinux0 < 4.2unaffected
LinuxLinux5.10.270 <= 5.10.*unaffected
LinuxLinux5.15.221 <= 5.15.*unaffected
LinuxLinux6.1.188 <= 6.1.*unaffected
LinuxLinux6.6.157 <= 6.6.*unaffected
LinuxLinux6.12.110 <= 6.12.*unaffected
LinuxLinux6.18.51 <= 6.18.*unaffected
LinuxLinux7.2.5 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References