From: Hoan Tran Date: Wed, 25 May 2016 19:09:23 +0000 (-0700) Subject: ACPI / CPPC: Prevent cpc_desc_ptr points to the invalid data X-Git-Tag: firefly_0821_release~176^2~4^2~31^2~282 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=5f009361d67ddf6d8a26e5605f083e795d49c0f4;p=firefly-linux-kernel-4.4.55.git ACPI / CPPC: Prevent cpc_desc_ptr points to the invalid data commit 2324d15447a9db168b1f85e3feac635b1ff8edb8 upstream. When CPPC fails to request a PCC channel, the CPC data is freed and cpc_desc_ptr points to the invalid data. Avoid this issue by moving the cpc_desc_ptr assignment after the PCC channel request. Signed-off-by: Hoan Tran Acked-by: Ashwin Chaugule Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index 079b8db32dfe..0afd1981e350 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -508,9 +508,6 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) /* Store CPU Logical ID */ cpc_ptr->cpu_id = pr->id; - /* Plug it into this CPUs CPC descriptor. */ - per_cpu(cpc_desc_ptr, pr->id) = cpc_ptr; - /* Parse PSD data for this CPU */ ret = acpi_get_psd(cpc_ptr, handle); if (ret) @@ -523,6 +520,9 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) goto out_free; } + /* Plug PSD data into this CPUs CPC descriptor. */ + per_cpu(cpc_desc_ptr, pr->id) = cpc_ptr; + /* Everything looks okay */ pr_debug("Parsed CPC struct for CPU: %d\n", pr->id);