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/builtin-version.c | 46 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 tools/perf/builtin-version.c (limited to 'tools/perf/builtin-version.c') diff --git a/tools/perf/builtin-version.c b/tools/perf/builtin-version.c new file mode 100644 index 000000000..10f25c670 --- /dev/null +++ b/tools/perf/builtin-version.c @@ -0,0 +1,46 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "builtin.h" +#include "color.h" +#include "util/debug.h" +#include "util/header.h" +#include +#include +#include +#include +#include + +struct version { + bool build_options; +}; + +static struct version version; + +static struct option version_options[] = { + OPT_BOOLEAN(0, "build-options", &version.build_options, + "display the build options"), + OPT_END(), +}; + +static const char * const version_usage[] = { + "perf version []", + NULL +}; + +static void library_status(void) +{ + for (int i = 0; supported_features[i].name; ++i) + feature_status__printf(&supported_features[i]); +} + +int cmd_version(int argc, const char **argv) +{ + argc = parse_options(argc, argv, version_options, version_usage, + PARSE_OPT_STOP_AT_NON_OPTION); + + printf("perf version %s\n", perf_version_string); + + if (version.build_options || verbose > 0) + library_status(); + + return 0; +} -- cgit v1.3.1