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/cache.h | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 tools/perf/util/cache.h (limited to 'tools/perf/util/cache.h') diff --git a/tools/perf/util/cache.h b/tools/perf/util/cache.h new file mode 100644 index 000000000..0b61840d4 --- /dev/null +++ b/tools/perf/util/cache.h @@ -0,0 +1,31 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __PERF_CACHE_H +#define __PERF_CACHE_H + +#include "strbuf.h" +#include +#include "../ui/ui.h" + +#include +#include + +#define CMD_EXEC_PATH "--exec-path" +#define CMD_DEBUGFS_DIR "--debugfs-dir=" + +#define EXEC_PATH_ENVIRONMENT "PERF_EXEC_PATH" +#define PERF_DEBUGFS_ENVIRONMENT "PERF_DEBUGFS_DIR" +#define PERF_TRACEFS_ENVIRONMENT "PERF_TRACEFS_DIR" +#define PERF_PAGER_ENVIRONMENT "PERF_PAGER" + +int split_cmdline(char *cmdline, const char ***argv); + +#define alloc_nr(x) (((x)+16)*3/2) + +static inline int is_absolute_path(const char *path) +{ + return path[0] == '/'; +} + +char *mkpath(char *path_buf, size_t sz, const char *fmt, ...) __printf(3, 4); + +#endif /* __PERF_CACHE_H */ -- cgit v1.3.1