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/tests/demangle-ocaml-test.c | 44 ++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 tools/perf/tests/demangle-ocaml-test.c (limited to 'tools/perf/tests/demangle-ocaml-test.c') diff --git a/tools/perf/tests/demangle-ocaml-test.c b/tools/perf/tests/demangle-ocaml-test.c new file mode 100644 index 000000000..612c788b7 --- /dev/null +++ b/tools/perf/tests/demangle-ocaml-test.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include "debug.h" +#include "symbol.h" +#include "tests.h" + +static int test__demangle_ocaml(struct test_suite *test __maybe_unused, int subtest __maybe_unused) +{ + int ret = TEST_OK; + char *buf = NULL; + size_t i; + + struct { + const char *mangled, *demangled; + } test_cases[] = { + { "main", + NULL }, + { "camlStdlib__array__map_154", + "Stdlib.array.map_154" }, + { "camlStdlib__anon_fn$5bstdlib$2eml$3a334$2c0$2d$2d54$5d_1453", + "Stdlib.anon_fn[stdlib.ml:334,0--54]_1453" }, + { "camlStdlib__bytes__$2b$2b_2205", + "Stdlib.bytes.++_2205" }, + }; + + for (i = 0; i < ARRAY_SIZE(test_cases); i++) { + buf = dso__demangle_sym(/*dso=*/NULL, /*kmodule=*/0, test_cases[i].mangled); + if ((buf == NULL && test_cases[i].demangled != NULL) + || (buf != NULL && test_cases[i].demangled == NULL) + || (buf != NULL && strcmp(buf, test_cases[i].demangled))) { + pr_debug("FAILED: %s: %s != %s\n", test_cases[i].mangled, + buf == NULL ? "(null)" : buf, + test_cases[i].demangled == NULL ? "(null)" : test_cases[i].demangled); + ret = TEST_FAIL; + } + free(buf); + } + + return ret; +} + +DEFINE_SUITE("Demangle OCaml", demangle_ocaml); -- cgit v1.3.1