[PATCH V2] cpufreq: scmi: Avoid overflow of target_freq in fast switch

From: Jagadeesh Kona
Date: Mon May 20 2024 - 02:38:22 EST


Conversion of target_freq to HZ in scmi_cpufreq_fast_switch()
can lead to overflow if the multiplied result is greater than
UINT_MAX, since type of target_freq is unsigned int. Avoid this
overflow by assigning target_freq to unsigned long variable for
converting it to HZ.

Signed-off-by: Jagadeesh Kona <quic_jkona@xxxxxxxxxxx>
---
Changes in V2:
- Updated freq variable from u64 to unsigned long to keep it
consistent with the rate parameter in scmi .freq_set() callback
- Link to v1: https://lore.kernel.org/all/20240517070157.19553-1-quic_jkona@xxxxxxxxxxx/
---
drivers/cpufreq/scmi-cpufreq.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c
index 3b4f6bfb2f4c..b87fd127aa43 100644
--- a/drivers/cpufreq/scmi-cpufreq.c
+++ b/drivers/cpufreq/scmi-cpufreq.c
@@ -63,9 +63,9 @@ static unsigned int scmi_cpufreq_fast_switch(struct cpufreq_policy *policy,
unsigned int target_freq)
{
struct scmi_data *priv = policy->driver_data;
+ unsigned long freq = target_freq;

- if (!perf_ops->freq_set(ph, priv->domain_id,
- target_freq * 1000, true))
+ if (!perf_ops->freq_set(ph, priv->domain_id, freq * 1000, true))
return target_freq;

return 0;
--
2.43.0