[dpdk-dev] [PATCH v3 1/1] power: check freq count before filling the freqs array

[Richael Zhuang <richael.zhuang@arm.com>]

The freqs array size is RTE_MAX_LCORE_FREQS. Before filling the
array with num_freqs elements, restrict the total num to
RTE_MAX_LCORE_FREQS. This fix aims to fix the coverity scan issue
like:
Overrunning array "pi->freqs" of 256 bytes by passing it to a
function which accesses it at byte offset 464.

Coverity issue: 371913
Fixes: ef1cc88f1837 ("power: support cppc_cpufreq driver")
Cc: richael.zhuang@arm.com
Cc: stable@dpdk.org

Signed-off-by: Richael Zhuang <richael.zhuang@arm.com>
---
 lib/power/power_cppc_cpufreq.c   | 5 +++++
 lib/power/power_pstate_cpufreq.c | 5 +++++
 2 files changed, 10 insertions(+)

diff --git a/lib/power/power_cppc_cpufreq.c b/lib/power/power_cppc_cpufreq.c
index e92973ab54..db63c2cc10 100644
--- a/lib/power/power_cppc_cpufreq.c
+++ b/lib/power/power_cppc_cpufreq.c
@@ -246,6 +246,11 @@ power_get_available_freqs(struct cppc_power_info *pi)
 			pi->nominal_perf * UNIT_DIFF : pi->nominal_perf;
 	num_freqs = (nominal_perf - scaling_min_freq) / BUS_FREQ + 1 +
 		pi->turbo_available;
+	if (num_freqs >= RTE_MAX_LCORE_FREQS) {
+		RTE_LOG(ERR, POWER, "Too many available frequencies : %d\n",
+				num_freqs);
+		goto out;
+	}
 
 	/* Generate the freq bucket array. */
 	for (i = 0, pi->nb_freqs = 0; i < num_freqs; i++) {
diff --git a/lib/power/power_pstate_cpufreq.c b/lib/power/power_pstate_cpufreq.c
index 3b607515fd..619090c8d1 100644
--- a/lib/power/power_pstate_cpufreq.c
+++ b/lib/power/power_pstate_cpufreq.c
@@ -419,6 +419,11 @@ power_get_available_freqs(struct pstate_power_info *pi)
 	 */
 	num_freqs = (base_max_freq - sys_min_freq) / BUS_FREQ + 1 +
 		pi->turbo_available;
+	if (num_freqs >= RTE_MAX_LCORE_FREQS) {
+		RTE_LOG(ERR, POWER, "Too many available frequencies : %d\n",
+				num_freqs);
+		goto out;
+	}
 
 	/* Generate the freq bucket array.
 	 * If turbo is available the freq bucket[0] value is base_max +1
-- 
2.20.1