kernel/linux.git/drivers/input/mouse/alps.c, branch v6.12.80

Input: alps - fix use-after-free bugs caused by dev3_register_work

2026-01-08T09:14:06+00:00

commit bf40644ef8c8a288742fa45580897ed0e0289474 upstream. The dev3_register_work delayed work item is initialized within alps_reconnect() and scheduled upon receipt of the first bare PS/2 packet from an external PS/2 device connected to the ALPS touchpad. During device detachment, the original implementation calls flush_workqueue() in psmouse_disconnect() to ensure completion of dev3_register_work. However, the flush_workqueue() in psmouse_disconnect() only blocks and waits for work items that were already queued to the workqueue prior to its invocation. Any work items submitted after flush_workqueue() is called are not included in the set of tasks that the flush operation awaits. This means that after flush_workqueue() has finished executing, the dev3_register_work could still be scheduled. Although the psmouse state is set to PSMOUSE_CMD_MODE in psmouse_disconnect(), the scheduling of dev3_register_work remains unaffected. The race condition can occur as follows: CPU 0 (cleanup path) | CPU 1 (delayed work) psmouse_disconnect() | psmouse_set_state() | flush_workqueue() | alps_report_bare_ps2_packet() alps_disconnect() | psmouse_queue_work() kfree(priv); // FREE | alps_register_bare_ps2_mouse() | priv = container_of(work...); // USE | priv->dev3 // USE Add disable_delayed_work_sync() in alps_disconnect() to ensure that dev3_register_work is properly canceled and prevented from executing after the alps_data structure has been deallocated. This bug is identified by static analysis. Fixes: 04aae283ba6a ("Input: ALPS - do not mix trackstick and external PS/2 mouse data") Cc: stable@kernel.org Signed-off-by: Duoming Zhou Link: https://patch.msgid.link/b57b0a9ccca51a3f06be141bfc02b9ffe69d1845.1765939397.git.duoming@zju.edu.cn Signed-off-by: Dmitry Torokhov Signed-off-by: Greg Kroah-Hartman

Input: alps - use guard notation when acquiring mutex

2024-09-06T05:52:37+00:00

This makes the code more compact and error handling more robust by ensuring that mutexes are released in all code paths when control leaves critical section. Acked-by: Pali Rohár Link: https://lore.kernel.org/r/ZsrBkWIpyEqzClUG@google.com Signed-off-by: Dmitry Torokhov

Input: mouse - use sizeof(*pointer) instead of sizeof(type)

2024-06-03T04:32:02+00:00

It is preferred to use sizeof(*pointer) instead of sizeof(type) due to the type of the variable can change and one needs not change the former (unlike the latter). This patch has no effect on runtime behavior. Signed-off-by: Erick Archer Link: https://lore.kernel.org/r/AS8PR02MB7237FB736DBF67A58798FDF38BFE2@AS8PR02MB7237.eurprd02.prod.outlook.com Signed-off-by: Dmitry Torokhov

Input: alps - fix compatibility with -funsigned-char

2023-03-20T06:07:04+00:00

The AlpsPS/2 code previously relied on the assumption that `char` is a signed type, which was true on x86 platforms (the only place where this driver is used) before kernel 6.2. However, on 6.2 and later, this assumption is broken due to the introduction of -funsigned-char as a new global compiler flag. Fix this by explicitly specifying the signedness of `char` when sign extending the values received from the device. Fixes: f3f33c677699 ("Input: alps - Rushmore and v7 resolution support") Signed-off-by: msizanoen Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20230320045228.182259-1-msizanoen@qtmlabs.xyz Signed-off-by: Dmitry Torokhov

treewide: Convert del_timer() to timer_shutdown()

2022-12-25T21:38:09+00:00

Due to several bugs caused by timers being re-armed after they are shutdown and just before they are freed, a new state of timers was added called "shutdown". After a timer is set to this state, then it can no longer be re-armed. The following script was run to find all the trivial locations where del_timer() or del_timer_sync() is called in the same function that the object holding the timer is freed. It also ignores any locations where the timer->function is modified between the del_timer*() and the free(), as that is not considered a "trivial" case. This was created by using a coccinelle script and the following commands: $ cat timer.cocci @@ expression ptr, slab; identifier timer, rfield; @@ ( - del_timer(&ptr->timer); + timer_shutdown(&ptr->timer); | - del_timer_sync(&ptr->timer); + timer_shutdown_sync(&ptr->timer); ) ... when strict when != ptr->timer ( kfree_rcu(ptr, rfield); | kmem_cache_free(slab, ptr); | kfree(ptr); ) $ spatch timer.cocci . > /tmp/t.patch $ patch -p1 < /tmp/t.patch Link: https://lore.kernel.org/lkml/20221123201306.823305113@linutronix.de/ Signed-off-by: Steven Rostedt (Google) Acked-by: Pavel Machek [ LED ] Acked-by: Kalle Valo [ wireless ] Acked-by: Paolo Abeni [ networking ] Signed-off-by: Linus Torvalds

Input: alps - fix spelling of "positive"

2021-02-23T05:22:47+00:00

s/postive/positive/ Signed-off-by: Bhaskar Chowdhury Acked-by: Randy Dunlap Reviewed-by: Pali Rohár Link: https://lore.kernel.org/r/20210222075439.32201-1-unixbhaskar@gmail.com Signed-off-by: Dmitry Torokhov

Input: alps - remove redundant assignment to variable ret

2020-08-07T00:33:41+00:00

The variable ret is being initialized with a value that is never read and it is being updated later with a new value. The initialization is redundant and can be removed. Addresses-Coverity: ("Unused value") Signed-off-by: Colin Ian King Link: https://lore.kernel.org/r/20200603135742.130852-1-colin.king@canonical.com Signed-off-by: Dmitry Torokhov

Input: alps - fix a mismatch between a condition check and its comment

2019-07-19T09:40:35+00:00

In the function alps_is_cs19_trackpoint(), we check if the param[1] is in the 0x20~0x2f range, but the code we wrote for this checking is not correct: (param[1] & 0x20) does not mean param[1] is in the range of 0x20~0x2f, it also means the param[1] is in the range of 0x30~0x3f, 0x60~0x6f... Now fix it with a new condition checking ((param[1] & 0xf0) == 0x20). Fixes: 7e4935ccc323 ("Input: alps - don't handle ALPS cs19 trackpoint-only device") Cc: stable@vger.kernel.org Signed-off-by: Hui Wang Signed-off-by: Dmitry Torokhov

Input: alps - don't handle ALPS cs19 trackpoint-only device

2019-07-15T17:19:08+00:00

On a latest Lenovo laptop, the trackpoint and 3 buttons below it don't work at all, when we move the trackpoint or press those 3 buttons, the kernel will print out: "Rejected trackstick packet from non DualPoint device" This device is identified as an alps touchpad but the packet has trackpoint format, so the alps.c drops the packet and prints out the message above. According to XiaoXiao's explanation, this device is named cs19 and is trackpoint-only device, its firmware is only for trackpoint, it is independent of touchpad and is a device completely different from DualPoint ones. To drive this device with mininal changes to the existing driver, we just let the alps driver not handle this device, then the trackpoint.c will be the driver of this device if the trackpoint driver is enabled. (if not, this device will fallback to a bare PS/2 device) With the trackpoint.c, this trackpoint and 3 buttons all work well, they have all features that the trackpoint should have, like scrolling-screen, drag-and-drop and frame-selection. Signed-off-by: XiaoXiao Liu Signed-off-by: Hui Wang Reviewed-by: Pali Rohár Cc: stable@vger.kernel.org Signed-off-by: Dmitry Torokhov

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55+00:00

Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Enrico Weigelt Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman