Commit 951ef0e1 authored Dec 08, 2017 by Colin Ian King Committed by Rafael J. Wysocki Dec 18, 2017

ACPI: CPPC: remove initial assignment of pcc_ss_data



The initialization of pcc_ss_data from pcc_data[pcc_ss_id] before
pcc_ss_id is being range checked could lead to an out-of-bounds array
read.  This very same initialization is also being performed after
the range check on pcc_ss_id, so we can just remove this problematic
and also redundant assignment to fix the issue.

Detected by cppcheck:
warning: Value stored to 'pcc_ss_data' during its initialization is never
read

Fixes: 85b1407b (ACPI / CPPC: Make CPPC ACPI driver aware of PCC subspace IDs)
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

parent 1291a0d5

drivers/acpi/cppc_acpi.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1171,7 +1171,7 @@ int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls)
		struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpu);
		struct cpc_register_resource *desired_reg;
		int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu);
		struct cppc_pcc_data *pcc_ss_data = pcc_data[pcc_ss_id];
		struct cppc_pcc_data *pcc_ss_data;
		int ret = 0;

		if (!cpc_desc \|\| pcc_ss_id < 0) {

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