From 071b24b54d2d05fbf39ddbb27dee08abd1d713f3 Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Sun, 27 Oct 2024 22:31:15 -0700 Subject: Input: fix regression when re-registering input handlers Commit d469647bafd9 ("Input: simplify event handling logic") introduced code that would set handler->events() method to either input_handler_events_filter() or input_handler_events_default() or input_handler_events_null(), depending on the kind of input handler (a filter or a regular one) we are dealing with. Unfortunately this breaks cases when we try to re-register the same filter (as is the case with sysrq handler): after initial registration the handler will have 2 event handling methods defined, and will run afoul of the check in input_handler_check_methods(): input: input_handler_check_methods: only one event processing method can be defined (sysrq) sysrq: Failed to register input handler, error -22 Fix this by adding handle_events() method to input_handle structure and setting it up when registering a new input handle according to event handling methods defined in associated input_handler structure, thus avoiding modifying the input_handler structure. Reported-by: "Ned T. Crigler" Reported-by: Christian Heusel Tested-by: "Ned T. Crigler" Tested-by: Peter Seiderer Fixes: d469647bafd9 ("Input: simplify event handling logic") Link: https://lore.kernel.org/r/Zx2iQp6csn42PJA7@xavtug Cc: stable@vger.kernel.org Signed-off-by: Dmitry Torokhov --- include/linux/input.h | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'include/linux/input.h') diff --git a/include/linux/input.h b/include/linux/input.h index 89a0be6ee0e2..cd866b020a01 100644 --- a/include/linux/input.h +++ b/include/linux/input.h @@ -339,12 +339,16 @@ struct input_handler { * @name: name given to the handle by handler that created it * @dev: input device the handle is attached to * @handler: handler that works with the device through this handle + * @handle_events: event sequence handler. It is set up by the input core + * according to event handling method specified in the @handler. See + * input_handle_setup_event_handler(). + * This method is being called by the input core with interrupts disabled + * and dev->event_lock spinlock held and so it may not sleep. * @d_node: used to put the handle on device's list of attached handles * @h_node: used to put the handle on handler's list of handles from which * it gets events */ struct input_handle { - void *private; int open; @@ -353,6 +357,10 @@ struct input_handle { struct input_dev *dev; struct input_handler *handler; + unsigned int (*handle_events)(struct input_handle *handle, + struct input_value *vals, + unsigned int count); + struct list_head d_node; struct list_head h_node; }; -- cgit v1.2.3-70-g09d2