From 78004e9a87f240df03e2f73120d291763c32e0a7 Mon Sep 17 00:00:00 2001 From: Ali Ahmet Memis Date: Fri, 21 Aug 2026 01:45:27 +0000 Subject: openrisc: fix arbitrary kernel memory access via or1k_atomic syscall sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user pointers, v1 and v2, and swaps the words they point to in hand-written assembly. l.lwz r29,0(r4) l.lwz r27,0(r5) l.sw 0(r4),r27 l.sw 0(r5),r29 The pointers are not checked with access_ok(). The four memory accesses also have no exception table entries. A caller passes a kernel address as either pointer, and the syscall reads from and writes to it directly. This gives an unprivileged process a kernel read/write primitive. It overwrites kernel data such as the sys_call_table, gaining code execution in kernel context. Check both pointers before entering the critical section. Add fixups for the four memory accesses so faults on valid but unmapped user addresses return -EFAULT. [shorne@gmail.com: fix comment style] Fixes: 9d02a4283e9c ("OpenRISC: Boot code") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis Signed-off-by: Stafford Horne --- drivers/hid/hid-macally.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 drivers/hid/hid-macally.c (limited to 'drivers/hid/hid-macally.c') diff --git a/drivers/hid/hid-macally.c b/drivers/hid/hid-macally.c new file mode 100644 index 000000000..fe7576458 --- /dev/null +++ b/drivers/hid/hid-macally.c @@ -0,0 +1,45 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * HID driver for quirky Macally devices + * + * Copyright (c) 2019 Alex Henrie + */ + +#include +#include + +#include "hid-ids.h" + +MODULE_AUTHOR("Alex Henrie "); +MODULE_DESCRIPTION("Macally devices"); +MODULE_LICENSE("GPL"); + +/* + * The Macally ikey keyboard says that its logical and usage maximums are both + * 101, but the power key is 102 and the equals key is 103 + */ +static const __u8 *macally_report_fixup(struct hid_device *hdev, __u8 *rdesc, + unsigned int *rsize) +{ + if (*rsize >= 60 && rdesc[53] == 0x65 && rdesc[59] == 0x65) { + hid_info(hdev, + "fixing up Macally ikey keyboard report descriptor\n"); + rdesc[53] = rdesc[59] = 0x67; + } + return rdesc; +} + +static const struct hid_device_id macally_id_table[] = { + { HID_USB_DEVICE(USB_VENDOR_ID_SOLID_YEAR, + USB_DEVICE_ID_MACALLY_IKEY_KEYBOARD) }, + { } +}; +MODULE_DEVICE_TABLE(hid, macally_id_table); + +static struct hid_driver macally_driver = { + .name = "macally", + .id_table = macally_id_table, + .report_fixup = macally_report_fixup, +}; + +module_hid_driver(macally_driver); -- cgit v1.3.1