]> git.ipfire.org Git - thirdparty/kernel/linux.git/commitdiff
selftests/bpf: Add tests for extending sleepable global subprogs
authorKumar Kartikeya Dwivedi <memxor@gmail.com>
Sat, 1 Mar 2025 15:18:46 +0000 (07:18 -0800)
committerAlexei Starovoitov <ast@kernel.org>
Sat, 15 Mar 2025 18:48:25 +0000 (11:48 -0700)
Add tests for freplace behavior with the combination of sleepable
and non-sleepable global subprogs. The changes_pkt_data selftest
did all the hardwork, so simply rename it and include new support
for more summarization tests for might_sleep bit.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250301151846.1552362-4-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
tools/testing/selftests/bpf/prog_tests/changes_pkt_data.c [deleted file]
tools/testing/selftests/bpf/prog_tests/summarization.c [new file with mode: 0644]
tools/testing/selftests/bpf/progs/changes_pkt_data.c [deleted file]
tools/testing/selftests/bpf/progs/summarization.c [new file with mode: 0644]
tools/testing/selftests/bpf/progs/summarization_freplace.c [moved from tools/testing/selftests/bpf/progs/changes_pkt_data_freplace.c with 57% similarity]

diff --git a/tools/testing/selftests/bpf/prog_tests/changes_pkt_data.c b/tools/testing/selftests/bpf/prog_tests/changes_pkt_data.c
deleted file mode 100644 (file)
index 7526de3..0000000
+++ /dev/null
@@ -1,107 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-#include "bpf/libbpf.h"
-#include "changes_pkt_data_freplace.skel.h"
-#include "changes_pkt_data.skel.h"
-#include <test_progs.h>
-
-static void print_verifier_log(const char *log)
-{
-       if (env.verbosity >= VERBOSE_VERY)
-               fprintf(stdout, "VERIFIER LOG:\n=============\n%s=============\n", log);
-}
-
-static void test_aux(const char *main_prog_name,
-                    const char *to_be_replaced,
-                    const char *replacement,
-                    bool expect_load)
-{
-       struct changes_pkt_data_freplace *freplace = NULL;
-       struct bpf_program *freplace_prog = NULL;
-       struct bpf_program *main_prog = NULL;
-       LIBBPF_OPTS(bpf_object_open_opts, opts);
-       struct changes_pkt_data *main = NULL;
-       char log[16*1024];
-       int err;
-
-       opts.kernel_log_buf = log;
-       opts.kernel_log_size = sizeof(log);
-       if (env.verbosity >= VERBOSE_SUPER)
-               opts.kernel_log_level = 1 | 2 | 4;
-       main = changes_pkt_data__open_opts(&opts);
-       if (!ASSERT_OK_PTR(main, "changes_pkt_data__open"))
-               goto out;
-       main_prog = bpf_object__find_program_by_name(main->obj, main_prog_name);
-       if (!ASSERT_OK_PTR(main_prog, "main_prog"))
-               goto out;
-       bpf_program__set_autoload(main_prog, true);
-       err = changes_pkt_data__load(main);
-       print_verifier_log(log);
-       if (!ASSERT_OK(err, "changes_pkt_data__load"))
-               goto out;
-       freplace = changes_pkt_data_freplace__open_opts(&opts);
-       if (!ASSERT_OK_PTR(freplace, "changes_pkt_data_freplace__open"))
-               goto out;
-       freplace_prog = bpf_object__find_program_by_name(freplace->obj, replacement);
-       if (!ASSERT_OK_PTR(freplace_prog, "freplace_prog"))
-               goto out;
-       bpf_program__set_autoload(freplace_prog, true);
-       bpf_program__set_autoattach(freplace_prog, true);
-       bpf_program__set_attach_target(freplace_prog,
-                                      bpf_program__fd(main_prog),
-                                      to_be_replaced);
-       err = changes_pkt_data_freplace__load(freplace);
-       print_verifier_log(log);
-       if (expect_load) {
-               ASSERT_OK(err, "changes_pkt_data_freplace__load");
-       } else {
-               ASSERT_ERR(err, "changes_pkt_data_freplace__load");
-               ASSERT_HAS_SUBSTR(log, "Extension program changes packet data", "error log");
-       }
-
-out:
-       changes_pkt_data_freplace__destroy(freplace);
-       changes_pkt_data__destroy(main);
-}
-
-/* There are two global subprograms in both changes_pkt_data.skel.h:
- * - one changes packet data;
- * - another does not.
- * It is ok to freplace subprograms that change packet data with those
- * that either do or do not. It is only ok to freplace subprograms
- * that do not change packet data with those that do not as well.
- * The below tests check outcomes for each combination of such freplace.
- * Also test a case when main subprogram itself is replaced and is a single
- * subprogram in a program.
- */
-void test_changes_pkt_data_freplace(void)
-{
-       struct {
-               const char *main;
-               const char *to_be_replaced;
-               bool changes;
-       } mains[] = {
-               { "main_with_subprogs",   "changes_pkt_data",         true },
-               { "main_with_subprogs",   "does_not_change_pkt_data", false },
-               { "main_changes",         "main_changes",             true },
-               { "main_does_not_change", "main_does_not_change",     false },
-       };
-       struct {
-               const char *func;
-               bool changes;
-       } replacements[] = {
-               { "changes_pkt_data",         true },
-               { "does_not_change_pkt_data", false }
-       };
-       char buf[64];
-
-       for (int i = 0; i < ARRAY_SIZE(mains); ++i) {
-               for (int j = 0; j < ARRAY_SIZE(replacements); ++j) {
-                       snprintf(buf, sizeof(buf), "%s_with_%s",
-                                mains[i].to_be_replaced, replacements[j].func);
-                       if (!test__start_subtest(buf))
-                               continue;
-                       test_aux(mains[i].main, mains[i].to_be_replaced, replacements[j].func,
-                                mains[i].changes || !replacements[j].changes);
-               }
-       }
-}
diff --git a/tools/testing/selftests/bpf/prog_tests/summarization.c b/tools/testing/selftests/bpf/prog_tests/summarization.c
new file mode 100644 (file)
index 0000000..5dd6c12
--- /dev/null
@@ -0,0 +1,144 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "bpf/libbpf.h"
+#include "summarization_freplace.skel.h"
+#include "summarization.skel.h"
+#include <test_progs.h>
+
+static void print_verifier_log(const char *log)
+{
+       if (env.verbosity >= VERBOSE_VERY)
+               fprintf(stdout, "VERIFIER LOG:\n=============\n%s=============\n", log);
+}
+
+static void test_aux(const char *main_prog_name,
+                    const char *to_be_replaced,
+                    const char *replacement,
+                    bool expect_load,
+                    const char *err_msg)
+{
+       struct summarization_freplace *freplace = NULL;
+       struct bpf_program *freplace_prog = NULL;
+       struct bpf_program *main_prog = NULL;
+       LIBBPF_OPTS(bpf_object_open_opts, opts);
+       struct summarization *main = NULL;
+       char log[16*1024];
+       int err;
+
+       opts.kernel_log_buf = log;
+       opts.kernel_log_size = sizeof(log);
+       if (env.verbosity >= VERBOSE_SUPER)
+               opts.kernel_log_level = 1 | 2 | 4;
+       main = summarization__open_opts(&opts);
+       if (!ASSERT_OK_PTR(main, "summarization__open"))
+               goto out;
+       main_prog = bpf_object__find_program_by_name(main->obj, main_prog_name);
+       if (!ASSERT_OK_PTR(main_prog, "main_prog"))
+               goto out;
+       bpf_program__set_autoload(main_prog, true);
+       err = summarization__load(main);
+       print_verifier_log(log);
+       if (!ASSERT_OK(err, "summarization__load"))
+               goto out;
+       freplace = summarization_freplace__open_opts(&opts);
+       if (!ASSERT_OK_PTR(freplace, "summarization_freplace__open"))
+               goto out;
+       freplace_prog = bpf_object__find_program_by_name(freplace->obj, replacement);
+       if (!ASSERT_OK_PTR(freplace_prog, "freplace_prog"))
+               goto out;
+       bpf_program__set_autoload(freplace_prog, true);
+       bpf_program__set_autoattach(freplace_prog, true);
+       bpf_program__set_attach_target(freplace_prog,
+                                      bpf_program__fd(main_prog),
+                                      to_be_replaced);
+       err = summarization_freplace__load(freplace);
+       print_verifier_log(log);
+
+       /* The might_sleep extension doesn't work yet as sleepable calls are not
+        * allowed, but preserve the check in case it's supported later and then
+        * this particular combination can be enabled.
+        */
+       if (!strcmp("might_sleep", replacement) && err) {
+               ASSERT_HAS_SUBSTR(log, "helper call might sleep in a non-sleepable prog", "error log");
+               ASSERT_EQ(err, -EINVAL, "err");
+               test__skip();
+               goto out;
+       }
+
+       if (expect_load) {
+               ASSERT_OK(err, "summarization_freplace__load");
+       } else {
+               ASSERT_ERR(err, "summarization_freplace__load");
+               ASSERT_HAS_SUBSTR(log, err_msg, "error log");
+       }
+
+out:
+       summarization_freplace__destroy(freplace);
+       summarization__destroy(main);
+}
+
+/* There are two global subprograms in both summarization.skel.h:
+ * - one changes packet data;
+ * - another does not.
+ * It is ok to freplace subprograms that change packet data with those
+ * that either do or do not. It is only ok to freplace subprograms
+ * that do not change packet data with those that do not as well.
+ * The below tests check outcomes for each combination of such freplace.
+ * Also test a case when main subprogram itself is replaced and is a single
+ * subprogram in a program.
+ *
+ * This holds for might_sleep programs. It is ok to replace might_sleep with
+ * might_sleep and with does_not_sleep, but does_not_sleep cannot be replaced
+ * with might_sleep.
+ */
+void test_summarization_freplace(void)
+{
+       struct {
+               const char *main;
+               const char *to_be_replaced;
+               bool has_side_effect;
+       } mains[2][4] = {
+               {
+                       { "main_changes_with_subprogs",         "changes_pkt_data",         true },
+                       { "main_changes_with_subprogs",         "does_not_change_pkt_data", false },
+                       { "main_changes",                       "main_changes",             true },
+                       { "main_does_not_change",               "main_does_not_change",     false },
+               },
+               {
+                       { "main_might_sleep_with_subprogs",     "might_sleep",              true },
+                       { "main_might_sleep_with_subprogs",     "does_not_sleep",           false },
+                       { "main_might_sleep",                   "main_might_sleep",         true },
+                       { "main_does_not_sleep",                "main_does_not_sleep",      false },
+               },
+       };
+       const char *pkt_err = "Extension program changes packet data";
+       const char *slp_err = "Extension program may sleep";
+       struct {
+               const char *func;
+               bool has_side_effect;
+               const char *err_msg;
+       } replacements[2][2] = {
+               {
+                       { "changes_pkt_data",         true,     pkt_err },
+                       { "does_not_change_pkt_data", false,    pkt_err },
+               },
+               {
+                       { "might_sleep",              true,     slp_err },
+                       { "does_not_sleep",           false,    slp_err },
+               },
+       };
+       char buf[64];
+
+       for (int t = 0; t < 2; t++) {
+               for (int i = 0; i < ARRAY_SIZE(mains); ++i) {
+                       for (int j = 0; j < ARRAY_SIZE(replacements); ++j) {
+                               snprintf(buf, sizeof(buf), "%s_with_%s",
+                                        mains[t][i].to_be_replaced, replacements[t][j].func);
+                               if (!test__start_subtest(buf))
+                                       continue;
+                               test_aux(mains[t][i].main, mains[t][i].to_be_replaced, replacements[t][j].func,
+                                        mains[t][i].has_side_effect || !replacements[t][j].has_side_effect,
+                                        replacements[t][j].err_msg);
+                       }
+               }
+       }
+}
diff --git a/tools/testing/selftests/bpf/progs/changes_pkt_data.c b/tools/testing/selftests/bpf/progs/changes_pkt_data.c
deleted file mode 100644 (file)
index 43cada4..0000000
+++ /dev/null
@@ -1,39 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-
-#include <linux/bpf.h>
-#include <bpf/bpf_helpers.h>
-
-__noinline
-long changes_pkt_data(struct __sk_buff *sk)
-{
-       return bpf_skb_pull_data(sk, 0);
-}
-
-__noinline __weak
-long does_not_change_pkt_data(struct __sk_buff *sk)
-{
-       return 0;
-}
-
-SEC("?tc")
-int main_with_subprogs(struct __sk_buff *sk)
-{
-       changes_pkt_data(sk);
-       does_not_change_pkt_data(sk);
-       return 0;
-}
-
-SEC("?tc")
-int main_changes(struct __sk_buff *sk)
-{
-       bpf_skb_pull_data(sk, 0);
-       return 0;
-}
-
-SEC("?tc")
-int main_does_not_change(struct __sk_buff *sk)
-{
-       return 0;
-}
-
-char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/progs/summarization.c b/tools/testing/selftests/bpf/progs/summarization.c
new file mode 100644 (file)
index 0000000..f89effe
--- /dev/null
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_misc.h"
+
+__noinline
+long changes_pkt_data(struct __sk_buff *sk)
+{
+       return bpf_skb_pull_data(sk, 0);
+}
+
+__noinline __weak
+long does_not_change_pkt_data(struct __sk_buff *sk)
+{
+       return 0;
+}
+
+SEC("?tc")
+int main_changes_with_subprogs(struct __sk_buff *sk)
+{
+       changes_pkt_data(sk);
+       does_not_change_pkt_data(sk);
+       return 0;
+}
+
+SEC("?tc")
+int main_changes(struct __sk_buff *sk)
+{
+       bpf_skb_pull_data(sk, 0);
+       return 0;
+}
+
+SEC("?tc")
+int main_does_not_change(struct __sk_buff *sk)
+{
+       return 0;
+}
+
+__noinline
+long might_sleep(struct pt_regs *ctx __arg_ctx)
+{
+       int i;
+
+       bpf_copy_from_user(&i, sizeof(i), NULL);
+       return i;
+}
+
+__noinline __weak
+long does_not_sleep(struct pt_regs *ctx __arg_ctx)
+{
+       return 0;
+}
+
+SEC("?uprobe.s")
+int main_might_sleep_with_subprogs(struct pt_regs *ctx)
+{
+       might_sleep(ctx);
+       does_not_sleep(ctx);
+       return 0;
+}
+
+SEC("?uprobe.s")
+int main_might_sleep(struct pt_regs *ctx)
+{
+       int i;
+
+       bpf_copy_from_user(&i, sizeof(i), NULL);
+       return i;
+}
+
+SEC("?uprobe.s")
+int main_does_not_sleep(struct pt_regs *ctx)
+{
+       return 0;
+}
+
+char _license[] SEC("license") = "GPL";
similarity index 57%
rename from tools/testing/selftests/bpf/progs/changes_pkt_data_freplace.c
rename to tools/testing/selftests/bpf/progs/summarization_freplace.c
index f9a622705f1b3bb2d6eeadaa2234606be90385a4..935f00e0e9ea0966236cd8f9a53857bc509431e9 100644 (file)
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 
-#include <linux/bpf.h>
+#include <vmlinux.h>
 #include <bpf/bpf_helpers.h>
 
 SEC("?freplace")
@@ -15,4 +15,19 @@ long does_not_change_pkt_data(struct __sk_buff *sk)
        return 0;
 }
 
+SEC("?freplace")
+long might_sleep(struct pt_regs *ctx)
+{
+       int i;
+
+       bpf_copy_from_user(&i, sizeof(i), NULL);
+       return i;
+}
+
+SEC("?freplace")
+long does_not_sleep(struct pt_regs *ctx)
+{
+       return 0;
+}
+
 char _license[] SEC("license") = "GPL";