From: Amery Hung <ameryhung@gmail.com>
To: netdev@vger.kernel.org
Cc: bpf@vger.kernel.org, yangpeihao@sjtu.edu.cn,
daniel@iogearbox.net, andrii@kernel.org, martin.lau@kernel.org,
sinquersw@gmail.com, toke@redhat.com, jhs@mojatatu.com,
jiri@resnulli.us, sdf@google.com, xiyou.wangcong@gmail.com,
yepeilin.cs@gmail.com, ameryhung@gmail.com
Subject: [RFC PATCH v8 02/20] selftests/bpf: Test referenced kptr arguments of struct_ops programs
Date: Fri, 10 May 2024 19:23:54 +0000 [thread overview]
Message-ID: <20240510192412.3297104-3-amery.hung@bytedance.com> (raw)
In-Reply-To: <20240510192412.3297104-1-amery.hung@bytedance.com>
A reference is automatically acquired for a referenced kptr argument
annotated via the stub function with "__ref_acquired" in a struct_ops
program. It must be released and cannot be acquired more than once.
The test first checks whether a reference to the correct type is acquired
in "ref_acquire". Then, we check if the verifier correctly rejects the
program that fails to release the reference (i.e., reference leak) in
"ref_acquire_ref_leak". Finally, we check if the reference can be only
acquired once through the argument in "ref_acquire_dup_ref".
Signed-off-by: Amery Hung <amery.hung@bytedance.com>
---
.../selftests/bpf/bpf_testmod/bpf_testmod.c | 7 +++
.../selftests/bpf/bpf_testmod/bpf_testmod.h | 2 +
.../prog_tests/test_struct_ops_ref_acquire.c | 58 +++++++++++++++++++
.../bpf/progs/struct_ops_ref_acquire.c | 27 +++++++++
.../progs/struct_ops_ref_acquire_dup_ref.c | 24 ++++++++
.../progs/struct_ops_ref_acquire_ref_leak.c | 19 ++++++
6 files changed, 137 insertions(+)
create mode 100644 tools/testing/selftests/bpf/prog_tests/test_struct_ops_ref_acquire.c
create mode 100644 tools/testing/selftests/bpf/progs/struct_ops_ref_acquire.c
create mode 100644 tools/testing/selftests/bpf/progs/struct_ops_ref_acquire_dup_ref.c
create mode 100644 tools/testing/selftests/bpf/progs/struct_ops_ref_acquire_ref_leak.c
diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
index 39ad96a18123..64dcab25b539 100644
--- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
+++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
@@ -594,10 +594,17 @@ static int bpf_testmod_ops__test_maybe_null(int dummy,
return 0;
}
+static int bpf_testmod_ops__test_ref_acquire(int dummy,
+ struct task_struct *task__ref_acquired)
+{
+ return 0;
+}
+
static struct bpf_testmod_ops __bpf_testmod_ops = {
.test_1 = bpf_testmod_test_1,
.test_2 = bpf_testmod_test_2,
.test_maybe_null = bpf_testmod_ops__test_maybe_null,
+ .test_ref_acquire = bpf_testmod_ops__test_ref_acquire,
};
struct bpf_struct_ops bpf_bpf_testmod_ops = {
diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h
index 23fa1872ee67..a0233990fb0e 100644
--- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h
+++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h
@@ -35,6 +35,8 @@ struct bpf_testmod_ops {
void (*test_2)(int a, int b);
/* Used to test nullable arguments. */
int (*test_maybe_null)(int dummy, struct task_struct *task);
+ /* Used to test ref_acquired arguments. */
+ int (*test_ref_acquire)(int dummy, struct task_struct *task);
/* The following fields are used to test shadow copies. */
char onebyte;
diff --git a/tools/testing/selftests/bpf/prog_tests/test_struct_ops_ref_acquire.c b/tools/testing/selftests/bpf/prog_tests/test_struct_ops_ref_acquire.c
new file mode 100644
index 000000000000..779287a00ed8
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/test_struct_ops_ref_acquire.c
@@ -0,0 +1,58 @@
+#include <test_progs.h>
+
+#include "struct_ops_ref_acquire.skel.h"
+#include "struct_ops_ref_acquire_ref_leak.skel.h"
+#include "struct_ops_ref_acquire_dup_ref.skel.h"
+
+/* Test that the verifier accepts a program that acquires a referenced
+ * kptr and releases the reference
+ */
+static void ref_acquire(void)
+{
+ struct struct_ops_ref_acquire *skel;
+
+ skel = struct_ops_ref_acquire__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "struct_ops_module_open_and_load"))
+ return;
+
+ struct_ops_ref_acquire__destroy(skel);
+}
+
+/* Test that the verifier rejects a program that acquires a referenced
+ * kptr without releasing the reference
+ */
+static void ref_acquire_ref_leak(void)
+{
+ struct struct_ops_ref_acquire_ref_leak *skel;
+
+ skel = struct_ops_ref_acquire_ref_leak__open_and_load();
+ if (ASSERT_ERR_PTR(skel, "struct_ops_module_fail__open_and_load"))
+ return;
+
+ struct_ops_ref_acquire_ref_leak__destroy(skel);
+}
+
+/* Test that the verifier rejects a program that tries to acquire a
+ * referenced twice
+ */
+static void ref_acquire_dup_ref(void)
+{
+ struct struct_ops_ref_acquire_dup_ref *skel;
+
+ skel = struct_ops_ref_acquire_dup_ref__open_and_load();
+ if (ASSERT_ERR_PTR(skel, "struct_ops_module_fail__open_and_load"))
+ return;
+
+ struct_ops_ref_acquire_dup_ref__destroy(skel);
+}
+
+void test_struct_ops_ref_acquire(void)
+{
+ if (test__start_subtest("ref_acquire"))
+ ref_acquire();
+ if (test__start_subtest("ref_acquire_ref_leak"))
+ ref_acquire_ref_leak();
+ if (test__start_subtest("ref_acquire_dup_ref"))
+ ref_acquire_dup_ref();
+}
+
diff --git a/tools/testing/selftests/bpf/progs/struct_ops_ref_acquire.c b/tools/testing/selftests/bpf/progs/struct_ops_ref_acquire.c
new file mode 100644
index 000000000000..bae342db0fdb
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/struct_ops_ref_acquire.c
@@ -0,0 +1,27 @@
+#include <vmlinux.h>
+#include <bpf/bpf_tracing.h>
+#include "../bpf_testmod/bpf_testmod.h"
+
+char _license[] SEC("license") = "GPL";
+
+void bpf_task_release(struct task_struct *p) __ksym;
+
+/* This is a test BPF program that uses struct_ops to access a referenced
+ * kptr argument. This is a test for the verifier to ensure that it recongnizes
+ * the task as a referenced object (i.e., ref_obj_id > 0).
+ */
+SEC("struct_ops/test_ref_acquire")
+int BPF_PROG(test_ref_acquire, int dummy,
+ struct task_struct *task)
+{
+ bpf_task_release(task);
+
+ return 0;
+}
+
+SEC(".struct_ops.link")
+struct bpf_testmod_ops testmod_ref_acquire = {
+ .test_ref_acquire = (void *)test_ref_acquire,
+};
+
+
diff --git a/tools/testing/selftests/bpf/progs/struct_ops_ref_acquire_dup_ref.c b/tools/testing/selftests/bpf/progs/struct_ops_ref_acquire_dup_ref.c
new file mode 100644
index 000000000000..489db98a47fb
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/struct_ops_ref_acquire_dup_ref.c
@@ -0,0 +1,24 @@
+#include <vmlinux.h>
+#include <bpf/bpf_tracing.h>
+#include "../bpf_testmod/bpf_testmod.h"
+
+char _license[] SEC("license") = "GPL";
+
+void bpf_task_release(struct task_struct *p) __ksym;
+
+SEC("struct_ops/test_ref_acquire")
+int BPF_PROG(test_ref_acquire, int dummy,
+ struct task_struct *task)
+{
+ bpf_task_release(task);
+ bpf_task_release(task);
+
+ return 0;
+}
+
+SEC(".struct_ops.link")
+struct bpf_testmod_ops testmod_ref_acquire = {
+ .test_ref_acquire = (void *)test_ref_acquire,
+};
+
+
diff --git a/tools/testing/selftests/bpf/progs/struct_ops_ref_acquire_ref_leak.c b/tools/testing/selftests/bpf/progs/struct_ops_ref_acquire_ref_leak.c
new file mode 100644
index 000000000000..c5b9a1d748a1
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/struct_ops_ref_acquire_ref_leak.c
@@ -0,0 +1,19 @@
+#include <vmlinux.h>
+#include <bpf/bpf_tracing.h>
+#include "../bpf_testmod/bpf_testmod.h"
+
+char _license[] SEC("license") = "GPL";
+
+SEC("struct_ops/test_ref_acquire")
+int BPF_PROG(test_ref_acquire, int dummy,
+ struct task_struct *task)
+{
+ return 0;
+}
+
+SEC(".struct_ops.link")
+struct bpf_testmod_ops testmod_ref_acquire = {
+ .test_ref_acquire = (void *)test_ref_acquire,
+};
+
+
--
2.20.1
next prev parent reply other threads:[~2024-05-10 19:24 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-10 19:23 [RFC PATCH v8 00/20] bpf qdisc Amery Hung
2024-05-10 19:23 ` [RFC PATCH v8 01/20] bpf: Support passing referenced kptr to struct_ops programs Amery Hung
2024-05-16 23:59 ` Kumar Kartikeya Dwivedi
2024-05-17 0:17 ` Amery Hung
2024-05-17 0:23 ` Kumar Kartikeya Dwivedi
2024-05-17 1:22 ` Amery Hung
2024-05-17 2:00 ` Kumar Kartikeya Dwivedi
2024-05-10 19:23 ` Amery Hung [this message]
2024-05-10 21:33 ` [RFC PATCH v8 02/20] selftests/bpf: Test referenced kptr arguments of " Kui-Feng Lee
2024-05-10 22:16 ` Amery Hung
2024-05-16 23:14 ` Amery Hung
2024-05-16 23:43 ` Martin KaFai Lau
2024-05-17 0:54 ` Amery Hung
2024-05-17 1:07 ` Martin KaFai Lau
2024-05-10 19:23 ` [RFC PATCH v8 03/20] bpf: Allow struct_ops prog to return referenced kptr Amery Hung
2024-05-17 2:06 ` Amery Hung
2024-05-17 5:30 ` Martin KaFai Lau
2024-05-10 19:23 ` [RFC PATCH v8 04/20] selftests/bpf: Test returning kptr from struct_ops programs Amery Hung
2024-05-10 19:23 ` [RFC PATCH v8 05/20] bpf: Generate btf_struct_metas for kernel BTF Amery Hung
2024-05-10 19:23 ` [RFC PATCH v8 06/20] bpf: Recognize kernel types as graph values Amery Hung
2024-05-10 19:23 ` [RFC PATCH v8 07/20] bpf: Allow adding kernel objects to collections Amery Hung
2024-05-10 19:24 ` [RFC PATCH v8 08/20] selftests/bpf: Test adding kernel object to bpf graph Amery Hung
2024-05-10 19:24 ` [RFC PATCH v8 09/20] bpf: Find special BTF fields in union Amery Hung
2024-05-16 23:37 ` Amery Hung
2024-05-10 19:24 ` [RFC PATCH v8 10/20] bpf: Introduce exclusive-ownership list and rbtree nodes Amery Hung
2024-05-10 19:24 ` [RFC PATCH v8 11/20] bpf: Allow adding exclusive nodes to bpf list and rbtree Amery Hung
2024-05-10 19:24 ` [RFC PATCH v8 12/20] selftests/bpf: Modify linked_list tests to work with macro-ified removes Amery Hung
2024-05-10 19:24 ` [RFC PATCH v8 13/20] bpf: net_sched: Support implementation of Qdisc_ops in bpf Amery Hung
2024-05-10 19:24 ` [RFC PATCH v8 14/20] bpf: net_sched: Add bpf qdisc kfuncs Amery Hung
2024-05-22 23:55 ` Martin KaFai Lau
2024-05-23 1:06 ` Amery Hung
2024-05-10 19:24 ` [RFC PATCH v8 15/20] bpf: net_sched: Allow more optional methods in Qdisc_ops Amery Hung
2024-05-10 19:24 ` [RFC PATCH v8 16/20] libbpf: Support creating and destroying qdisc Amery Hung
2024-05-10 19:24 ` [RFC PATCH v8 17/20] selftests: Add a basic fifo qdisc test Amery Hung
2024-05-21 3:15 ` Stanislav Fomichev
2024-05-21 15:03 ` Amery Hung
2024-05-21 17:57 ` Stanislav Fomichev
2024-05-10 19:24 ` [RFC PATCH v8 18/20] selftests: Add a bpf fq qdisc to selftest Amery Hung
2024-05-24 6:24 ` Martin KaFai Lau
2024-05-24 7:40 ` Toke Høiland-Jørgensen
2024-05-26 1:08 ` Martin KaFai Lau
2024-05-27 10:09 ` Toke Høiland-Jørgensen
2024-05-24 19:33 ` Alexei Starovoitov
2024-05-24 20:54 ` Martin KaFai Lau
2024-05-10 19:24 ` [RFC PATCH v8 19/20] selftests: Add a bpf netem " Amery Hung
2024-05-10 19:24 ` [RFC PATCH v8 20/20] selftests: Add a prio bpf qdisc Amery Hung
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20240510192412.3297104-3-amery.hung@bytedance.com \
--to=ameryhung@gmail.com \
--cc=andrii@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=jhs@mojatatu.com \
--cc=jiri@resnulli.us \
--cc=martin.lau@kernel.org \
--cc=netdev@vger.kernel.org \
--cc=sdf@google.com \
--cc=sinquersw@gmail.com \
--cc=toke@redhat.com \
--cc=xiyou.wangcong@gmail.com \
--cc=yangpeihao@sjtu.edu.cn \
--cc=yepeilin.cs@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).