drm/amd/pm: Prevent division by zero

commit 7d641c2b83275d3b0424127b2e0d2d0f7dd82aef upstream.

The user can set any speed value.
If speed is greater than UINT_MAX/8, division by zero is possible.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: b64625a303 ("drm/amd/pm: correct the address of Arcturus fan related registers")
Signed-off-by: Denis Arefev <arefev@swemel.ru>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Denis Arefev
2025-03-21 13:52:32 +03:00
committed by Greg Kroah-Hartman
parent 2a2b7b6f90
commit 6413fed016

View File

@@ -1267,6 +1267,9 @@ static int arcturus_set_fan_speed_rpm(struct smu_context *smu,
uint32_t crystal_clock_freq = 2500;
uint32_t tach_period;
if (!speed || speed > UINT_MAX/8)
return -EINVAL;
tach_period = 60 * crystal_clock_freq * 10000 / (8 * speed);
WREG32_SOC15(THM, 0, mmCG_TACH_CTRL_ARCT,
REG_SET_FIELD(RREG32_SOC15(THM, 0, mmCG_TACH_CTRL_ARCT),