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authorChao Qin <chao.qin@intel.com>2022-09-20 14:08:26 +0800
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2022-09-21 20:16:15 +0200
commit2d93540014387d1c73b9ccc4d7895320df66d01b (patch)
treee6054b5bfebf3e81b14d55e878e6c5a4a5e1e770 /drivers/powercap
parent0d7a23b5f8e162bf2c5caab06f5df4aee2619073 (diff)
powercap: intel_rapl: fix UBSAN shift-out-of-bounds issue
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>
Diffstat (limited to 'drivers/powercap')
-rw-r--r--drivers/powercap/intel_rapl_common.c3
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/powercap/intel_rapl_common.c b/drivers/powercap/intel_rapl_common.c
index 6812c1ca3100..4688d0647b22 100644
--- a/drivers/powercap/intel_rapl_common.c
+++ b/drivers/powercap/intel_rapl_common.c
@@ -994,6 +994,9 @@ 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);