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authorKees Cook <kees+treewide@kernel.org>2026-09-02 15:31:14 -0700
committerKees Cook <kees@kernel.org>2026-09-04 21:37:00 -0700
commit3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch)
treec65086f9bdcd48c6360fb7cb4598bca084da1f32 /lib/tests/test_fprobe.c
downloadlinux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz
linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'lib/tests/test_fprobe.c')
-rw-r--r--lib/tests/test_fprobe.c327
1 files changed, 327 insertions, 0 deletions
diff --git a/lib/tests/test_fprobe.c b/lib/tests/test_fprobe.c
new file mode 100644
index 000000000..108c7aa33
--- /dev/null
+++ b/lib/tests/test_fprobe.c
@@ -0,0 +1,327 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * test_fprobe.c - simple sanity test for fprobe
+ */
+
+#include <linux/kernel.h>
+#include <linux/fprobe.h>
+#include <linux/random.h>
+#include <kunit/test.h>
+
+#define div_factor 3
+
+static struct kunit *current_test;
+
+static u32 rand1, entry_only_val, entry_val, exit_val;
+static u32 entry_only_count, entry_count, exit_count;
+
+/* Use indirect calls to avoid inlining the target functions */
+static u32 (*target)(u32 value);
+static u32 (*target2)(u32 value);
+static unsigned long target_ip;
+static unsigned long target2_ip;
+static int entry_return_value;
+
+static noinline u32 fprobe_selftest_target(u32 value)
+{
+ return (value / div_factor);
+}
+
+static noinline u32 fprobe_selftest_target2(u32 value)
+{
+ return (value / div_factor) + 1;
+}
+
+static notrace int fp_entry_handler(struct fprobe *fp, unsigned long ip,
+ unsigned long ret_ip,
+ struct ftrace_regs *fregs, void *data)
+{
+ KUNIT_EXPECT_FALSE(current_test, preemptible());
+ /* This can be called on the fprobe_selftest_target and the fprobe_selftest_target2 */
+ if (ip != target_ip)
+ KUNIT_EXPECT_EQ(current_test, ip, target2_ip);
+ entry_val = (rand1 / div_factor);
+ if (fp->entry_data_size) {
+ KUNIT_EXPECT_NOT_NULL(current_test, data);
+ if (data)
+ *(u32 *)data = entry_val;
+ } else
+ KUNIT_EXPECT_NULL(current_test, data);
+
+ return entry_return_value;
+}
+
+static notrace void fp_exit_handler(struct fprobe *fp, unsigned long ip,
+ unsigned long ret_ip,
+ struct ftrace_regs *fregs, void *data)
+{
+ unsigned long ret = ftrace_regs_get_return_value(fregs);
+
+ KUNIT_EXPECT_FALSE(current_test, preemptible());
+ if (ip != target_ip) {
+ KUNIT_EXPECT_EQ(current_test, ip, target2_ip);
+ KUNIT_EXPECT_EQ(current_test, ret, (rand1 / div_factor) + 1);
+ } else
+ KUNIT_EXPECT_EQ(current_test, ret, (rand1 / div_factor));
+ KUNIT_EXPECT_EQ(current_test, entry_val, (rand1 / div_factor));
+ exit_val = entry_val + div_factor;
+ if (fp->entry_data_size) {
+ KUNIT_EXPECT_NOT_NULL(current_test, data);
+ if (data)
+ KUNIT_EXPECT_EQ(current_test, *(u32 *)data, entry_val);
+ } else
+ KUNIT_EXPECT_NULL(current_test, data);
+}
+
+/* Test entry only (no rethook) */
+static void test_fprobe_entry(struct kunit *test)
+{
+ struct fprobe fp_entry = {
+ .entry_handler = fp_entry_handler,
+ };
+
+ current_test = test;
+
+ /* Before register, unregister should be failed. */
+ KUNIT_EXPECT_NE(test, 0, unregister_fprobe(&fp_entry));
+ KUNIT_EXPECT_EQ(test, 0, register_fprobe(&fp_entry, "fprobe_selftest_target*", NULL));
+
+ entry_val = 0;
+ exit_val = 0;
+ target(rand1);
+ KUNIT_EXPECT_NE(test, 0, entry_val);
+ KUNIT_EXPECT_EQ(test, 0, exit_val);
+
+ entry_val = 0;
+ exit_val = 0;
+ target2(rand1);
+ KUNIT_EXPECT_NE(test, 0, entry_val);
+ KUNIT_EXPECT_EQ(test, 0, exit_val);
+
+ KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp_entry));
+}
+
+static void test_fprobe(struct kunit *test)
+{
+ struct fprobe fp = {
+ .entry_handler = fp_entry_handler,
+ .exit_handler = fp_exit_handler,
+ };
+
+ current_test = test;
+ KUNIT_EXPECT_EQ(test, 0, register_fprobe(&fp, "fprobe_selftest_target*", NULL));
+
+ entry_val = 0;
+ exit_val = 0;
+ target(rand1);
+ KUNIT_EXPECT_NE(test, 0, entry_val);
+ KUNIT_EXPECT_EQ(test, entry_val + div_factor, exit_val);
+
+ entry_val = 0;
+ exit_val = 0;
+ target2(rand1);
+ KUNIT_EXPECT_NE(test, 0, entry_val);
+ KUNIT_EXPECT_EQ(test, entry_val + div_factor, exit_val);
+
+ KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp));
+}
+
+static void test_fprobe_syms(struct kunit *test)
+{
+ static const char *syms[] = {"fprobe_selftest_target", "fprobe_selftest_target2"};
+ struct fprobe fp = {
+ .entry_handler = fp_entry_handler,
+ .exit_handler = fp_exit_handler,
+ };
+
+ current_test = test;
+ KUNIT_EXPECT_EQ(test, 0, register_fprobe_syms(&fp, syms, 2));
+
+ entry_val = 0;
+ exit_val = 0;
+ target(rand1);
+ KUNIT_EXPECT_NE(test, 0, entry_val);
+ KUNIT_EXPECT_EQ(test, entry_val + div_factor, exit_val);
+
+ entry_val = 0;
+ exit_val = 0;
+ target2(rand1);
+ KUNIT_EXPECT_NE(test, 0, entry_val);
+ KUNIT_EXPECT_EQ(test, entry_val + div_factor, exit_val);
+
+ KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp));
+}
+
+/* Test private entry_data */
+static void test_fprobe_data(struct kunit *test)
+{
+ struct fprobe fp = {
+ .entry_handler = fp_entry_handler,
+ .exit_handler = fp_exit_handler,
+ .entry_data_size = sizeof(u32),
+ };
+
+ current_test = test;
+ KUNIT_EXPECT_EQ(test, 0, register_fprobe(&fp, "fprobe_selftest_target", NULL));
+
+ target(rand1);
+
+ KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp));
+}
+
+static void test_fprobe_skip(struct kunit *test)
+{
+ struct fprobe fp = {
+ .entry_handler = fp_entry_handler,
+ .exit_handler = fp_exit_handler,
+ };
+
+ current_test = test;
+ KUNIT_EXPECT_EQ(test, 0, register_fprobe(&fp, "fprobe_selftest_target", NULL));
+
+ entry_return_value = 1;
+ entry_val = 0;
+ exit_val = 0;
+ target(rand1);
+ KUNIT_EXPECT_NE(test, 0, entry_val);
+ KUNIT_EXPECT_EQ(test, 0, exit_val);
+ KUNIT_EXPECT_EQ(test, 0, fp.nmissed);
+ entry_return_value = 0;
+
+ KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp));
+}
+
+/* Handler for fprobe entry only case */
+static notrace int entry_only_handler(struct fprobe *fp, unsigned long ip,
+ unsigned long ret_ip,
+ struct ftrace_regs *fregs, void *data)
+{
+ KUNIT_EXPECT_FALSE(current_test, preemptible());
+ KUNIT_EXPECT_EQ(current_test, ip, target_ip);
+
+ entry_only_count++;
+ entry_only_val = (rand1 / div_factor);
+
+ return 0;
+}
+
+static notrace int fprobe_entry_multi_handler(struct fprobe *fp, unsigned long ip,
+ unsigned long ret_ip,
+ struct ftrace_regs *fregs,
+ void *data)
+{
+ KUNIT_EXPECT_FALSE(current_test, preemptible());
+ KUNIT_EXPECT_EQ(current_test, ip, target_ip);
+
+ entry_count++;
+ entry_val = (rand1 / div_factor);
+
+ return 0;
+}
+
+static notrace void fprobe_exit_multi_handler(struct fprobe *fp, unsigned long ip,
+ unsigned long ret_ip,
+ struct ftrace_regs *fregs,
+ void *data)
+{
+ unsigned long ret = ftrace_regs_get_return_value(fregs);
+
+ KUNIT_EXPECT_FALSE(current_test, preemptible());
+ KUNIT_EXPECT_EQ(current_test, ip, target_ip);
+ KUNIT_EXPECT_EQ(current_test, ret, (rand1 / div_factor));
+
+ exit_count++;
+ exit_val = ret;
+}
+
+static void check_fprobe_multi(struct kunit *test)
+{
+ entry_only_count = entry_count = exit_count = 0;
+ entry_only_val = entry_val = exit_val = 0;
+
+ target(rand1);
+
+ /* Verify all handlers were called */
+ KUNIT_EXPECT_EQ(test, 1, entry_only_count);
+ KUNIT_EXPECT_EQ(test, 1, entry_count);
+ KUNIT_EXPECT_EQ(test, 1, exit_count);
+
+ /* Verify values are correct */
+ KUNIT_EXPECT_EQ(test, (rand1 / div_factor), entry_only_val);
+ KUNIT_EXPECT_EQ(test, (rand1 / div_factor), entry_val);
+ KUNIT_EXPECT_EQ(test, (rand1 / div_factor), exit_val);
+}
+
+/* Test multiple fprobes hooking the same target function */
+static void test_fprobe_multi(struct kunit *test)
+{
+ struct fprobe fp1 = {
+ .entry_handler = fprobe_entry_multi_handler,
+ .exit_handler = fprobe_exit_multi_handler,
+ };
+ struct fprobe fp2 = {
+ .entry_handler = entry_only_handler,
+ };
+
+ current_test = test;
+
+ /* Test Case 1: Register in order 1 -> 2 */
+ KUNIT_EXPECT_EQ(test, 0, register_fprobe(&fp1, "fprobe_selftest_target", NULL));
+ KUNIT_EXPECT_EQ(test, 0, register_fprobe(&fp2, "fprobe_selftest_target", NULL));
+
+ check_fprobe_multi(test);
+
+ /* Unregister all */
+ KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp1));
+ KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp2));
+
+ /* Test Case 2: Register in order 2 -> 1 */
+ KUNIT_EXPECT_EQ(test, 0, register_fprobe(&fp2, "fprobe_selftest_target", NULL));
+ KUNIT_EXPECT_EQ(test, 0, register_fprobe(&fp1, "fprobe_selftest_target", NULL));
+
+ check_fprobe_multi(test);
+
+ /* Unregister all */
+ KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp1));
+ KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp2));
+}
+
+static unsigned long get_ftrace_location(void *func)
+{
+ unsigned long size, addr = (unsigned long)func;
+
+ if (!kallsyms_lookup_size_offset(addr, &size, NULL) || !size)
+ return 0;
+
+ return ftrace_location_range(addr, addr + size - 1);
+}
+
+static int fprobe_test_init(struct kunit *test)
+{
+ rand1 = get_random_u32_above(div_factor);
+ target = fprobe_selftest_target;
+ target2 = fprobe_selftest_target2;
+ target_ip = get_ftrace_location(target);
+ target2_ip = get_ftrace_location(target2);
+
+ return 0;
+}
+
+static struct kunit_case fprobe_testcases[] = {
+ KUNIT_CASE(test_fprobe_entry),
+ KUNIT_CASE(test_fprobe),
+ KUNIT_CASE(test_fprobe_syms),
+ KUNIT_CASE(test_fprobe_data),
+ KUNIT_CASE(test_fprobe_skip),
+ KUNIT_CASE(test_fprobe_multi),
+ {}
+};
+
+static struct kunit_suite fprobe_test_suite = {
+ .name = "fprobe_test",
+ .init = fprobe_test_init,
+ .test_cases = fprobe_testcases,
+};
+
+kunit_test_suites(&fprobe_test_suite);
+