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-maltron.c | 166 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 166 insertions(+) create mode 100644 drivers/hid/hid-maltron.c (limited to 'drivers/hid/hid-maltron.c') diff --git a/drivers/hid/hid-maltron.c b/drivers/hid/hid-maltron.c new file mode 100644 index 000000000..f0aad1ba2 --- /dev/null +++ b/drivers/hid/hid-maltron.c @@ -0,0 +1,166 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * HID driver for Maltron L90 + * + * Copyright (c) 1999 Andreas Gal + * Copyright (c) 2000-2005 Vojtech Pavlik + * Copyright (c) 2005 Michael Haboustak for Concept2, Inc + * Copyright (c) 2008 Jiri Slaby + * Copyright (c) 2012 David Dillow + * Copyright (c) 2006-2013 Jiri Kosina + * Copyright (c) 2013 Colin Leitner + * Copyright (c) 2014-2016 Frank Praznik + * Copyright (c) 2010 Richard Nauber + * Copyright (c) 2016 Yuxuan Shui + * Copyright (c) 2018 William Whistler + */ + +#include +#include +#include + +#include "hid-ids.h" + +/* The original buggy USB descriptor */ +static const u8 maltron_rdesc_o[] = { + 0x05, 0x01, /* Usage Page (Generic Desktop Ctrls) */ + 0x09, 0x80, /* Usage (Sys Control) */ + 0xA1, 0x01, /* Collection (Application) */ + 0x85, 0x02, /* Report ID (2) */ + 0x75, 0x01, /* Report Size (1) */ + 0x95, 0x01, /* Report Count (1) */ + 0x15, 0x00, /* Logical Minimum (0) */ + 0x25, 0x01, /* Logical Maximum (1) */ + 0x09, 0x82, /* Usage (Sys Sleep) */ + 0x81, 0x06, /* Input (Data,Var,Rel) */ + 0x09, 0x82, /* Usage (Sys Sleep) */ + 0x81, 0x06, /* Input (Data,Var,Rel) */ + 0x09, 0x83, /* Usage (Sys Wake Up) */ + 0x81, 0x06, /* Input (Data,Var,Rel) */ + 0x75, 0x05, /* Report Size (5) */ + 0x81, 0x01, /* Input (Const,Array,Abs) */ + 0xC0, /* End Collection */ + 0x05, 0x0C, /* Usage Page (Consumer) */ + 0x09, 0x01, /* Usage (Consumer Control) */ + 0xA1, 0x01, /* Collection (Application) */ + 0x85, 0x03, /* Report ID (3) */ + 0x95, 0x01, /* Report Count (1) */ + 0x75, 0x10, /* Report Size (16) */ + 0x19, 0x00, /* Usage Minimum (Unassigned) */ + 0x2A, 0xFF, 0x7F, /* Usage Maximum (0x7FFF) */ + 0x81, 0x00, /* Input (Data,Array,Abs) */ + 0xC0, /* End Collection */ + 0x06, 0x7F, 0xFF, /* Usage Page (Vendor Defined 0xFF7F) */ + 0x09, 0x01, /* Usage (0x01) */ + 0xA1, 0x01, /* Collection (Application) */ + 0x85, 0x04, /* Report ID (4) */ + 0x95, 0x01, /* Report Count (1) */ + 0x75, 0x10, /* Report Size (16) */ + 0x19, 0x00, /* Usage Minimum (0x00) */ + 0x2A, 0xFF, 0x7F, /* Usage Maximum (0x7FFF) */ + 0x81, 0x00, /* Input (Data,Array,Abs) */ + 0x75, 0x02, /* Report Size (2) */ + 0x25, 0x02, /* Logical Maximum (2) */ + 0x09, 0x90, /* Usage (0x90) */ + 0xB1, 0x02, /* Feature (Data,Var,Abs) */ + 0x75, 0x06, /* Report Size (6) */ + 0xB1, 0x01, /* Feature (Const,Array,Abs) */ + 0x75, 0x01, /* Report Size (1) */ + 0x25, 0x01, /* Logical Maximum (1) */ + 0x05, 0x08, /* Usage Page (LEDs) */ + 0x09, 0x2A, /* Usage (On-Line) */ + 0x91, 0x02, /* Output (Data,Var,Abs) */ + 0x09, 0x4B, /* Usage (Generic Indicator) */ + 0x91, 0x02, /* Output (Data,Var,Abs) */ + 0x75, 0x06, /* Report Size (6) */ + 0x95, 0x01, /* Report Count (1) */ + 0x91, 0x01, /* Output (Const,Array,Abs) */ + 0xC0 /* End Collection */ +}; + +/* The patched descriptor, allowing media key events to be accepted as valid */ +static const u8 maltron_rdesc[] = { + 0x05, 0x01, /* Usage Page (Generic Desktop Ctrls) */ + 0x09, 0x80, /* Usage (Sys Control) */ + 0xA1, 0x01, /* Collection (Application) */ + 0x85, 0x02, /* Report ID (2) */ + 0x75, 0x01, /* Report Size (1) */ + 0x95, 0x01, /* Report Count (1) */ + 0x15, 0x00, /* Logical Minimum (0) */ + 0x25, 0x01, /* Logical Maximum (1) */ + 0x09, 0x82, /* Usage (Sys Sleep) */ + 0x81, 0x06, /* Input (Data,Var,Rel) */ + 0x09, 0x82, /* Usage (Sys Sleep) */ + 0x81, 0x06, /* Input (Data,Var,Rel) */ + 0x09, 0x83, /* Usage (Sys Wake Up) */ + 0x81, 0x06, /* Input (Data,Var,Rel) */ + 0x75, 0x05, /* Report Size (5) */ + 0x81, 0x01, /* Input (Const,Array,Abs) */ + 0xC0, /* End Collection */ + 0x05, 0x0C, /* Usage Page (Consumer) */ + 0x09, 0x01, /* Usage (Consumer Control) */ + 0xA1, 0x01, /* Collection (Application) */ + 0x85, 0x03, /* Report ID (3) */ + 0x15, 0x00, /* Logical Minimum (0) - changed */ + 0x26, 0xFF, 0x7F, /* Logical Maximum (32767) - changed */ + 0x95, 0x01, /* Report Count (1) */ + 0x75, 0x10, /* Report Size (16) */ + 0x19, 0x00, /* Usage Minimum (Unassigned) */ + 0x2A, 0xFF, 0x7F, /* Usage Maximum (0x7FFF) */ + 0x81, 0x00, /* Input (Data,Array,Abs) */ + 0xC0, /* End Collection */ + 0x06, 0x7F, 0xFF, /* Usage Page (Vendor Defined 0xFF7F) */ + 0x09, 0x01, /* Usage (0x01) */ + 0xA1, 0x01, /* Collection (Application) */ + 0x85, 0x04, /* Report ID (4) */ + 0x95, 0x01, /* Report Count (1) */ + 0x75, 0x10, /* Report Size (16) */ + 0x19, 0x00, /* Usage Minimum (0x00) */ + 0x2A, 0xFF, 0x7F, /* Usage Maximum (0x7FFF) */ + 0x81, 0x00, /* Input (Data,Array,Abs) */ + 0x75, 0x02, /* Report Size (2) */ + 0x25, 0x02, /* Logical Maximum (2) */ + 0x09, 0x90, /* Usage (0x90) */ + 0xB1, 0x02, /* Feature (Data,Var,Abs) */ + 0x75, 0x06, /* Report Size (6) */ + 0xB1, 0x01, /* Feature (Const,Array,Abs) */ + 0x75, 0x01, /* Report Size (1) */ + 0x25, 0x01, /* Logical Maximum (1) */ + 0x05, 0x08, /* Usage Page (LEDs) */ + 0x09, 0x2A, /* Usage (On-Line) */ + 0x91, 0x02, /* Output (Data,Var,Abs) */ + 0x09, 0x4B, /* Usage (Generic Indicator) */ + 0x91, 0x02, /* Output (Data,Var,Abs) */ + 0x75, 0x06, /* Report Size (6) */ + 0x95, 0x01, /* Report Count (1) */ + 0x91, 0x01, /* Output (Const,Array,Abs) */ + 0xC0 /* End Collection */ +}; + +static const __u8 *maltron_report_fixup(struct hid_device *hdev, __u8 *rdesc, + unsigned int *rsize) +{ + if (*rsize == sizeof(maltron_rdesc_o) && + !memcmp(maltron_rdesc_o, rdesc, sizeof(maltron_rdesc_o))) { + hid_info(hdev, "Replacing Maltron L90 keyboard report descriptor\n"); + *rsize = sizeof(maltron_rdesc); + return maltron_rdesc; + } + return rdesc; +} + +static const struct hid_device_id maltron_devices[] = { + { HID_USB_DEVICE(USB_VENDOR_ID_ALCOR, USB_DEVICE_ID_ALCOR_MALTRON_KB)}, + { } +}; +MODULE_DEVICE_TABLE(hid, maltron_devices); + +static struct hid_driver maltron_driver = { + .name = "maltron", + .id_table = maltron_devices, + .report_fixup = maltron_report_fixup +}; +module_hid_driver(maltron_driver); + +MODULE_DESCRIPTION("HID driver for Maltron L90"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1