High · published July 25, 2026
In the Linux kernel, the following vulnerability has been resolved:
cpufreq: pcc: fix use-after-free and double free in _OSC evaluation
pcc_cpufreq_do_osc() calls acpi_evaluate_object() twice for the
two-phase _OSC negotiation. Between the two calls it freed
output.pointer but left output.length unchanged. Since
acpi_evaluate_object() treats a non-zero length with a non-NULL
pointer as an existing buffer to write into, the second call wrote
into freed memory (use-after-free). The subsequent kfree(output.pointer)
at out_free then freed the same pointer a second time (double free).
Reset output.pointer to NULL and output.length to ACPI_ALLOCATE_BUFFER
after freeing the first result, so ACPICA allocates a fresh buffer for
each phase independently.
| Product | Versions | Fixed in |
|---|---|---|
| linux/linux_kernel | ≥ 2.6.34, < 5.10.261 | 5.10.261 |
| linux/linux_kernel | ≥ 5.11, < 5.15.212 | 5.15.212 |
| linux/linux_kernel | ≥ 5.16, < 6.1.178 | 6.1.178 |
| linux/linux_kernel | ≥ 6.2, < 6.6.145 | 6.6.145 |
| linux/linux_kernel | ≥ 6.7, < 6.12.96 | 6.12.96 |
| linux/linux_kernel | ≥ 6.13, < 6.18.39 | 6.18.39 |
| linux/linux_kernel | ≥ 6.19, < 7.1.4 | 7.1.4 |