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 --- tools/perf/util/call-path.h | 68 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) create mode 100644 tools/perf/util/call-path.h (limited to 'tools/perf/util/call-path.h') diff --git a/tools/perf/util/call-path.h b/tools/perf/util/call-path.h new file mode 100644 index 000000000..5875cfc81 --- /dev/null +++ b/tools/perf/util/call-path.h @@ -0,0 +1,68 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * call-path.h: Manipulate a tree data structure containing function call paths + * Copyright (c) 2014, Intel Corporation. + */ + +#ifndef __PERF_CALL_PATH_H +#define __PERF_CALL_PATH_H + +#include + +#include +#include + +/** + * struct call_path - node in list of calls leading to a function call. + * @parent: call path to the parent function call + * @sym: symbol of function called + * @ip: only if sym is null, the ip of the function + * @db_id: id used for db-export + * @in_kernel: whether function is a in the kernel + * @rb_node: node in parent's tree of called functions + * @children: tree of call paths of functions called + * + * In combination with the call_return structure, the call_path structure + * defines a context-sensitive call-graph. + */ +struct call_path { + struct call_path *parent; + struct symbol *sym; + u64 ip; + u64 db_id; + bool in_kernel; + struct rb_node rb_node; + struct rb_root children; +}; + +#define CALL_PATH_BLOCK_SHIFT 8 +#define CALL_PATH_BLOCK_SIZE (1 << CALL_PATH_BLOCK_SHIFT) +#define CALL_PATH_BLOCK_MASK (CALL_PATH_BLOCK_SIZE - 1) + +struct call_path_block { + struct call_path cp[CALL_PATH_BLOCK_SIZE]; + struct list_head node; +}; + +/** + * struct call_path_root - root of all call paths. + * @call_path: root call path + * @blocks: list of blocks to store call paths + * @next: next free space + * @sz: number of spaces + */ +struct call_path_root { + struct call_path call_path; + struct list_head blocks; + size_t next; + size_t sz; +}; + +struct call_path_root *call_path_root__new(void); +void call_path_root__free(struct call_path_root *cpr); + +struct call_path *call_path__findnew(struct call_path_root *cpr, + struct call_path *parent, + struct symbol *sym, u64 ip, u64 ks); + +#endif -- cgit v1.3.1