commit e4c3e133294c0a292d21073899b05ebf530169bd upstream. The ceiling value isn't checked before writing it into registers. The user could write a value higher than the counter resolution (e.g. 16 or 32 bits indicated by max_arr). This makes most significant bits to be truncated. Fix it by checking the max_arr to report a range error [1] to the user. [1] https://lkml.org/lkml/2021/2/12/358 Fixes: ad29937e206f ("counter: Add STM32 Timer quadrature encoder") Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com> Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> Cc: <Stable@vger.kernel.org> Link: https://lore.kernel.org/r/1614696235-24088-1-git-send-email-fabrice.gasnier@foss.st.com Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>