From: Hao Luo <haoluo@google.com>
To: Alexei Starovoitov <ast@kernel.org>,
Andrii Nakryiko <andrii@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <kafai@fb.com>, Song Liu <songliubraving@fb.com>,
Yonghong Song <yhs@fb.com>, KP Singh <kpsingh@kernel.org>,
bpf@vger.kernel.org, Hao Luo <haoluo@google.com>
Subject: [PATCH bpf-next v2 9/9] bpf/selftests: Test PTR_TO_RDONLY_MEM
Date: Thu, 16 Dec 2021 16:31:52 -0800 [thread overview]
Message-ID: <20211217003152.48334-10-haoluo@google.com> (raw)
In-Reply-To: <20211217003152.48334-1-haoluo@google.com>
This test verifies that a ksym of non-struct can not be directly
updated.
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Hao Luo <haoluo@google.com>
---
.../selftests/bpf/prog_tests/ksyms_btf.c | 14 +++++++++
.../bpf/progs/test_ksyms_btf_write_check.c | 29 +++++++++++++++++++
2 files changed, 43 insertions(+)
create mode 100644 tools/testing/selftests/bpf/progs/test_ksyms_btf_write_check.c
diff --git a/tools/testing/selftests/bpf/prog_tests/ksyms_btf.c b/tools/testing/selftests/bpf/prog_tests/ksyms_btf.c
index 79f6bd1e50d6..f6933b06daf8 100644
--- a/tools/testing/selftests/bpf/prog_tests/ksyms_btf.c
+++ b/tools/testing/selftests/bpf/prog_tests/ksyms_btf.c
@@ -8,6 +8,7 @@
#include "test_ksyms_btf_null_check.skel.h"
#include "test_ksyms_weak.skel.h"
#include "test_ksyms_weak.lskel.h"
+#include "test_ksyms_btf_write_check.skel.h"
static int duration;
@@ -137,6 +138,16 @@ static void test_weak_syms_lskel(void)
test_ksyms_weak_lskel__destroy(skel);
}
+static void test_write_check(void)
+{
+ struct test_ksyms_btf_write_check *skel;
+
+ skel = test_ksyms_btf_write_check__open_and_load();
+ ASSERT_ERR_PTR(skel, "unexpected load of a prog writing to ksym memory\n");
+
+ test_ksyms_btf_write_check__destroy(skel);
+}
+
void test_ksyms_btf(void)
{
int percpu_datasec;
@@ -167,4 +178,7 @@ void test_ksyms_btf(void)
if (test__start_subtest("weak_ksyms_lskel"))
test_weak_syms_lskel();
+
+ if (test__start_subtest("write_check"))
+ test_write_check();
}
diff --git a/tools/testing/selftests/bpf/progs/test_ksyms_btf_write_check.c b/tools/testing/selftests/bpf/progs/test_ksyms_btf_write_check.c
new file mode 100644
index 000000000000..2180c41cd890
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_ksyms_btf_write_check.c
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Google */
+
+#include "vmlinux.h"
+
+#include <bpf/bpf_helpers.h>
+
+extern const int bpf_prog_active __ksym; /* int type global var. */
+
+SEC("raw_tp/sys_enter")
+int handler(const void *ctx)
+{
+ int *active;
+ __u32 cpu;
+
+ cpu = bpf_get_smp_processor_id();
+ active = (int *)bpf_per_cpu_ptr(&bpf_prog_active, cpu);
+ if (active) {
+ /* Kernel memory obtained from bpf_{per,this}_cpu_ptr
+ * is read-only, should _not_ pass verification.
+ */
+ /* WRITE_ONCE */
+ *(volatile int *)active = -1;
+ }
+
+ return 0;
+}
+
+char _license[] SEC("license") = "GPL";
--
2.34.1.173.g76aa8bc2d0-goog
prev parent reply other threads:[~2021-12-17 0:32 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-12-17 0:31 [PATCH bpf-next v2 0/9] Introduce composable bpf types Hao Luo
2021-12-17 0:31 ` [PATCH bpf-next v2 1/9] bpf: Introduce composable reg, ret and arg types Hao Luo
2021-12-17 0:31 ` [PATCH bpf-next v2 2/9] bpf: Replace ARG_XXX_OR_NULL with ARG_XXX | PTR_MAYBE_NULL Hao Luo
2021-12-17 0:31 ` [PATCH bpf-next v2 3/9] bpf: Replace RET_XXX_OR_NULL with RET_XXX " Hao Luo
2021-12-17 0:31 ` [PATCH bpf-next v2 4/9] bpf: Replace PTR_TO_XXX_OR_NULL with PTR_TO_XXX " Hao Luo
2021-12-18 21:48 ` Alexei Starovoitov
2021-12-17 0:31 ` [PATCH bpf-next v2 5/9] bpf: Introduce MEM_RDONLY flag Hao Luo
2021-12-17 0:31 ` [PATCH bpf-next v2 6/9] bpf: Convert PTR_TO_MEM_OR_NULL to composable types Hao Luo
2021-12-17 0:31 ` [PATCH bpf-next v2 7/9] bpf: Make per_cpu_ptr return rdonly PTR_TO_MEM Hao Luo
2021-12-18 21:48 ` Alexei Starovoitov
2021-12-17 0:31 ` [PATCH bpf-next v2 8/9] bpf: Add MEM_RDONLY for helper args that are pointers to rdonly mem Hao Luo
2021-12-18 21:48 ` Alexei Starovoitov
2021-12-20 20:14 ` Hao Luo
2021-12-17 0:31 ` Hao Luo [this message]
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=20211217003152.48334-10-haoluo@google.com \
--to=haoluo@google.com \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=kafai@fb.com \
--cc=kpsingh@kernel.org \
--cc=songliubraving@fb.com \
--cc=yhs@fb.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 NNTP newsgroup(s).