Messages in this thread | | | Date | Fri, 19 Nov 2021 15:54:42 +0100 (CET) | From | Jiri Kosina <> | Subject | Re: [PATCH] HID: magicmouse: prevent division by 0 on scroll |
| |
On Sun, 14 Nov 2021, Claudia Pellegrino wrote:
> In hid_magicmouse, if the user has set scroll_speed to a value between > 55 and 63 and scrolls seven times in quick succession, the > step_hr variable in the magicmouse_emit_touch function becomes 0. > > That causes a division by zero further down in the function when > it does `step_x_hr /= step_hr`. > > To reproduce, create `/etc/modprobe.d/hid_magicmouse.conf` with the > following content: > > ``` > options hid_magicmouse scroll_acceleration=1 scroll_speed=55 > ``` > > Then reboot, connect a Magic Mouse and scroll seven times quickly. > The system will freeze for a minute, and after that `dmesg` will > confirm that a division by zero occurred. > > Enforce a minimum of 1 for the variable so the high resolution > step count can never reach 0 even at maximum scroll acceleration. > > Fixes: d4b9f10a0eb6 ("HID: magicmouse: enable high-resolution scroll") > > Signed-off-by: Claudia Pellegrino <linux@cpellegrino.de>
Applied, thank you.
-- Jiri Kosina SUSE Labs
| |