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/trace/index.rst | 110 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 110 insertions(+) create mode 100644 Documentation/trace/index.rst (limited to 'Documentation/trace/index.rst') diff --git a/Documentation/trace/index.rst b/Documentation/trace/index.rst new file mode 100644 index 000000000..5d9bf4694 --- /dev/null +++ b/Documentation/trace/index.rst @@ -0,0 +1,110 @@ +================================ +Linux Tracing Technologies Guide +================================ + +Tracing in the Linux kernel is a powerful mechanism that allows +developers and system administrators to analyze and debug system +behavior. This guide provides documentation on various tracing +frameworks and tools available in the Linux kernel. + +Introduction to Tracing +----------------------- + +This section provides an overview of Linux tracing mechanisms +and debugging approaches. + +.. toctree:: + :maxdepth: 1 + + debugging + tracepoints + tracepoint-analysis + ring-buffer-map + +Core Tracing Frameworks +----------------------- + +The following are the primary tracing frameworks integrated into +the Linux kernel. + +.. toctree:: + :maxdepth: 1 + + ftrace + ftrace-design + ftrace-uses + kprobes + kprobetrace + fprobetrace + eprobetrace + fprobe + ring-buffer-design + +Event Tracing and Analysis +-------------------------- + +A detailed explanation of event tracing mechanisms and their +applications. + +.. toctree:: + :maxdepth: 1 + + events + events-kmem + events-power + events-nmi + events-msr + events-pci + events-pci-controller + boottime-trace + histogram + histogram-design + +Hardware and Performance Tracing +-------------------------------- + +This section covers tracing features that monitor hardware +interactions and system performance. + +.. toctree:: + :maxdepth: 1 + + intel_th + stm + sys-t + coresight/index + rv/index + hisi-ptt + mmiotrace + hwlat_detector + osnoise-tracer + timerlat-tracer + +User-Space Tracing +------------------ + +These tools allow tracing user-space applications and +interactions. + +.. toctree:: + :maxdepth: 1 + + user_events + uprobetracer + +Remote Tracing +-------------- + +This section covers the framework to read compatible ring-buffers, written by +entities outside of the kernel (most likely firmware or hypervisor) + +.. toctree:: + :maxdepth: 1 + + remotes + +Additional Resources +-------------------- + +For more details, refer to the respective documentation of each +tracing tool and framework. -- cgit v1.3.1