From 836b2fe544a5e9b5ce116622cb36fba33838c6fd Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Fri, 4 Sep 2026 01:33:23 -0700 Subject: selftests/bpf: Check that JMP32 pointer vs zero jumps are not predicted Add jmp32_ptr_vs_zero_jne: the fall-through of the 32-bit compare, which the verifier used to skip, contains an out of bounds map value access, hence w/o the previous patch the program is accepted. See previous patch for detailed description. Reported-by: Nicholas Carlini Suggested-by: Nicholas Carlini Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/bpf/20260904083325.2083493-6-eddyz87@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- tools/perf/tests/perf-hooks.c | 49 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 tools/perf/tests/perf-hooks.c (limited to 'tools/perf/tests/perf-hooks.c') diff --git a/tools/perf/tests/perf-hooks.c b/tools/perf/tests/perf-hooks.c new file mode 100644 index 000000000..78cdeb896 --- /dev/null +++ b/tools/perf/tests/perf-hooks.c @@ -0,0 +1,49 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include + +#include "tests.h" +#include "debug.h" +#include "perf-hooks.h" + +static void sigsegv_handler(int sig __maybe_unused) +{ + pr_debug("SIGSEGV is observed as expected, try to recover.\n"); + perf_hooks__recover(); + signal(SIGSEGV, SIG_DFL); + raise(SIGSEGV); + exit(-1); +} + + +static void the_hook(void *_hook_flags) +{ + int *hook_flags = _hook_flags; + + *hook_flags = 1234; + + /* Generate a segfault, test perf_hooks__recover */ + raise(SIGSEGV); +} + +static int test__perf_hooks(struct test_suite *test __maybe_unused, int subtest __maybe_unused) +{ + int hook_flags = 0; + + signal(SIGSEGV, sigsegv_handler); + perf_hooks__set_hook("test", the_hook, &hook_flags); + perf_hooks__invoke_test(); + + /* hook is triggered? */ + if (hook_flags != 1234) { + pr_debug("Setting failed: %d (%p)\n", hook_flags, &hook_flags); + return TEST_FAIL; + } + + /* the buggy hook is removed? */ + if (perf_hooks__get_hook("test")) + return TEST_FAIL; + return TEST_OK; +} + +DEFINE_SUITE("perf hooks", perf_hooks); -- cgit v1.3.1