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-kernel-irq | 60 ++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-kernel-irq (limited to 'Documentation/ABI/testing/sysfs-kernel-irq') diff --git a/Documentation/ABI/testing/sysfs-kernel-irq b/Documentation/ABI/testing/sysfs-kernel-irq new file mode 100644 index 000000000..8910d0c4b --- /dev/null +++ b/Documentation/ABI/testing/sysfs-kernel-irq @@ -0,0 +1,60 @@ +What: /sys/kernel/irq +Date: September 2016 +KernelVersion: 4.9 +Contact: Craig Gallek +Description: Directory containing information about the system's IRQs. + Specifically, data from the associated struct irq_desc. + The information here is similar to that in /proc/interrupts + but in a more machine-friendly format. This directory contains + one subdirectory for each Linux IRQ number. + +What: /sys/kernel/irq//actions +Date: September 2016 +KernelVersion: 4.9 +Contact: Craig Gallek +Description: The IRQ action chain. A comma-separated list of zero or more + device names associated with this interrupt. + +What: /sys/kernel/irq//chip_name +Date: September 2016 +KernelVersion: 4.9 +Contact: Craig Gallek +Description: Human-readable chip name supplied by the associated device + driver. + +What: /sys/kernel/irq//hwirq +Date: September 2016 +KernelVersion: 4.9 +Contact: Craig Gallek +Description: When interrupt translation domains are used, this file contains + the underlying hardware IRQ number used for this Linux IRQ. + +What: /sys/kernel/irq//name +Date: September 2016 +KernelVersion: 4.9 +Contact: Craig Gallek +Description: Human-readable flow handler name as defined by the irq chip + driver. + +What: /sys/kernel/irq//per_cpu_count +Date: September 2016 +KernelVersion: 4.9 +Contact: Craig Gallek +Description: The number of times the interrupt has fired since boot. This + is a comma-separated list of counters; one per CPU in CPU id + order. NOTE: This file consistently shows counters for all + CPU ids. This differs from the behavior of /proc/interrupts + which only shows counters for online CPUs. + +What: /sys/kernel/irq//type +Date: September 2016 +KernelVersion: 4.9 +Contact: Craig Gallek +Description: The type of the interrupt. Either the string 'level' or 'edge'. + +What: /sys/kernel/irq//wakeup +Date: March 2018 +KernelVersion: 4.17 +Contact: Andy Shevchenko +Description: The wakeup state of the interrupt. Either the string + 'enabled' or 'disabled'. -- cgit v1.3.1