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 --- Documentation/ABI/testing/sysfs-driver-hid | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-driver-hid (limited to 'Documentation/ABI/testing/sysfs-driver-hid') diff --git a/Documentation/ABI/testing/sysfs-driver-hid b/Documentation/ABI/testing/sysfs-driver-hid new file mode 100644 index 000000000..a59533410 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-driver-hid @@ -0,0 +1,20 @@ +What: /sys/bus/usb/devices/-:./::./report_descriptor +What: /sys/class/bluetooth/hci/::./report_descriptor +What: /sys/class/hidraw/hidraw/device/report_descriptor +Date: Jan 2011 +KernelVersion: 2.0.39 +Contact: Alan Ott +Description: When read, this file returns the device's raw binary HID + report descriptor. + This file cannot be written. +Users: HIDAPI library (http://www.signal11.us/oss/hidapi) + +What: /sys/bus/usb/devices/-:./::./country +What: /sys/class/bluetooth/hci/::./country +What: /sys/class/hidraw/hidraw/device/country +Date: February 2015 +KernelVersion: 3.19 +Contact: Olivier Gay +Description: When read, this file returns the hex integer value in ASCII + of the device's HID country code (e.g. 21 for US). + This file cannot be written. -- cgit v1.3.1