From: Chao Qin chao.qin@intel.com
[ Upstream commit 2d93540014387d1c73b9ccc4d7895320df66d01b ]
When value < time_unit, the parameter of ilog2() will be zero and the return value is -1. u64(-1) is too large for shift exponent and then will trigger shift-out-of-bounds:
shift exponent 18446744073709551615 is too large for 32-bit type 'int' Call Trace: rapl_compute_time_window_core rapl_write_data_raw set_time_window store_constraint_time_window_us
Signed-off-by: Chao Qin chao.qin@intel.com Acked-by: Zhang Rui rui.zhang@intel.com Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/powercap/intel_rapl_common.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/powercap/intel_rapl_common.c b/drivers/powercap/intel_rapl_common.c index 70d6d52bc1e2..64a86990671a 100644 --- a/drivers/powercap/intel_rapl_common.c +++ b/drivers/powercap/intel_rapl_common.c @@ -938,6 +938,9 @@ static u64 rapl_compute_time_window_core(struct rapl_package *rp, u64 value, y = value & 0x1f; value = (1 << y) * (4 + f) * rp->time_unit / 4; } else { + if (value < rp->time_unit) + return 0; + do_div(value, rp->time_unit); y = ilog2(value); f = div64_u64(4 * (value - (1 << y)), 1 << y);