4c6bb91581
commit 35588314e963938dfdcdb792c9170108399377d6 upstream. The offset is just 32bits here so this can potentially overflow if somebody specifies a large value. Instead reduce the size to calculate the last possible offset. The error handling path incorrectly drops the reference to the user fence BO resulting in potential reference count underflow. Signed-off-by: Christian König <christian.koenig@amd.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>