[PATCH] PM / Domains: Fix integer overflows on u32 bit multiplies

From: Colin King
Date: Sun Feb 07 2021 - 17:47:59 EST


From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

There are three occurrances of u32 variables being multiplied by
1000 using 32 bit multiplies and the result being assigned to a
64 bit signed integer. These can potentially lead to a 32 bit
overflows, so fix this by casting 1000 to a UL first to force
a 64 bit multiply hence avoiding the overflow.

Addresses-Coverity: ("Unintentional integer overflow")
Fixes: 30f604283e05 ("PM / Domains: Allow domain power states to be read from DT")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
---
drivers/base/power/domain.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index aaf6c83b5cf6..ddeff69126ff 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -2831,10 +2831,10 @@ static int genpd_parse_state(struct genpd_power_state *genpd_state,

err = of_property_read_u32(state_node, "min-residency-us", &residency);
if (!err)
- genpd_state->residency_ns = 1000 * residency;
+ genpd_state->residency_ns = 1000UL * residency;

- genpd_state->power_on_latency_ns = 1000 * exit_latency;
- genpd_state->power_off_latency_ns = 1000 * entry_latency;
+ genpd_state->power_on_latency_ns = 1000UL * exit_latency;
+ genpd_state->power_off_latency_ns = 1000UL * entry_latency;
genpd_state->fwnode = &state_node->fwnode;

return 0;
--
2.29.2