From 6668ed271eaefaa63e686bdfbedaeb7b8e492722 Mon Sep 17 00:00:00 2001 From: Kumar Kartikeya Dwivedi Date: Fri, 4 Sep 2026 10:43:19 +0200 Subject: selftests/bpf: Reject graph kptr use after RCU unlock Add a sleepable verifier test that loads a graph-node local kptr in an explicit RCU read-side critical section, then passes its node to bpf_rbtree_remove() after the section ends. Before the verifier fix, the stale NON_OWN_REF flag makes the node look like a live borrowed reference and the program is accepted. After the fix, the pointer is demoted without NON_OWN_REF and the graph kfunc argument is rejected. Also exercise a graph kptr loaded while a spin lock provides implicit RCU protection. The pointer must be invalidated when the lock is released, which guards the required ordering between non-owning-reference invalidation and RCU demotion. Update the existing fault-protected load test state description. The post-unlock pointer no longer carries NON_OWN_REF, but remains readable because the load is rewritten to use BPF_PROBE_MEM. Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- drivers/hid/hid-rakk.c | 75 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 75 insertions(+) create mode 100644 drivers/hid/hid-rakk.c (limited to 'drivers/hid/hid-rakk.c') diff --git a/drivers/hid/hid-rakk.c b/drivers/hid/hid-rakk.c new file mode 100644 index 000000000..1140058a7 --- /dev/null +++ b/drivers/hid/hid-rakk.c @@ -0,0 +1,75 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * HID driver for Rakk devices + * + * Copyright (c) 2026 Karl Cayme + * + * The Rakk Dasig X gaming mouse has a faulty HID report descriptor that + * declares USAGE_MAXIMUM = 3 (buttons 1-3) while actually sending 5 button + * bits (REPORT_COUNT = 5). This causes the kernel to ignore side buttons + * (buttons 4 and 5). This driver fixes the descriptor so all 5 buttons + * are properly recognized across 3 modes (wired, dongle, and Bluetooth). + */ + +#include +#include +#include +#include "hid-ids.h" + +/* + * The faulty byte is at offset 17 in the report descriptor for all three + * connection modes (USB direct, wireless dongle, and Bluetooth). + * + * Bytes 16-17 are: 0x29 0x03 (USAGE_MAXIMUM = 3) + * The fix changes byte 17 to 0x05 (USAGE_MAXIMUM = 5). + * + * Original descriptor bytes 0-17: + * 05 01 09 02 a1 01 85 01 09 01 a1 00 05 09 19 01 29 03 + * ^^ + * Should be 0x05 to declare 5 buttons instead of 3. + */ +#define RAKK_RDESC_USAGE_MAX_OFFSET 17 +#define RAKK_RDESC_USAGE_MAX_ORIG 0x03 +#define RAKK_RDESC_USAGE_MAX_FIXED 0x05 +#define RAKK_RDESC_USB_SIZE 193 +#define RAKK_RDESC_DONGLE_SIZE 150 +#define RAKK_RDESC_BT_SIZE 89 + +static const __u8 *rakk_report_fixup(struct hid_device *hdev, __u8 *rdesc, + unsigned int *rsize) +{ + if (((*rsize == RAKK_RDESC_USB_SIZE && + hdev->product == USB_DEVICE_ID_TELINK_RAKK_DASIG_X) || + (*rsize == RAKK_RDESC_DONGLE_SIZE && + hdev->product == USB_DEVICE_ID_TELINK_RAKK_DASIG_X_DONGLE) || + (*rsize == RAKK_RDESC_BT_SIZE && + hdev->product == USB_DEVICE_ID_TELINK_RAKK_DASIG_X_BT)) && + rdesc[RAKK_RDESC_USAGE_MAX_OFFSET] == RAKK_RDESC_USAGE_MAX_ORIG) { + hid_info(hdev, "fixing Rakk Dasig X button count (3 -> 5)\n"); + rdesc[RAKK_RDESC_USAGE_MAX_OFFSET] = RAKK_RDESC_USAGE_MAX_FIXED; + } + + return rdesc; +} + +static const struct hid_device_id rakk_devices[] = { + { HID_USB_DEVICE(USB_VENDOR_ID_TELINK, + USB_DEVICE_ID_TELINK_RAKK_DASIG_X) }, + { HID_USB_DEVICE(USB_VENDOR_ID_TELINK, + USB_DEVICE_ID_TELINK_RAKK_DASIG_X_DONGLE) }, + { HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_TELINK, + USB_DEVICE_ID_TELINK_RAKK_DASIG_X_BT) }, + { } +}; +MODULE_DEVICE_TABLE(hid, rakk_devices); + +static struct hid_driver rakk_driver = { + .name = "rakk", + .id_table = rakk_devices, + .report_fixup = rakk_report_fixup, +}; +module_hid_driver(rakk_driver); + +MODULE_DESCRIPTION("HID driver for Rakk Dasig X mouse - fix side button support"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Karl Cayme"); -- cgit v1.3.1