From: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Date: Fri, 14 Jan 2022 22:09:52 +0530
Subject: selftests/bpf: Extend kfunc selftests
Patch-mainline: v5.18-rc1
Git-commit: c1ff181ffabc292abcd1832a1c83aac2bc499e71
References: jsc#PED-1377
Use the prog_test kfuncs to test the referenced PTR_TO_BTF_ID kfunc
support, and PTR_TO_CTX, PTR_TO_MEM argument passing support. Also
testing the various failure cases for invalid kfunc prototypes.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220114163953.1455836-10-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
net/bpf/test_run.c | 129 +++++++++++++++++++-
tools/testing/selftests/bpf/prog_tests/kfunc_call.c | 6
tools/testing/selftests/bpf/progs/kfunc_call_test.c | 52 +++++++-
tools/testing/selftests/bpf/verifier/calls.c | 75 +++++++++++
4 files changed, 258 insertions(+), 4 deletions(-)
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -233,6 +233,105 @@ struct sock * noinline bpf_kfunc_call_te
return sk;
}
+struct prog_test_ref_kfunc {
+ int a;
+ int b;
+ struct prog_test_ref_kfunc *next;
+};
+
+static struct prog_test_ref_kfunc prog_test_struct = {
+ .a = 42,
+ .b = 108,
+ .next = &prog_test_struct,
+};
+
+noinline struct prog_test_ref_kfunc *
+bpf_kfunc_call_test_acquire(unsigned long *scalar_ptr)
+{
+ /* randomly return NULL */
+ if (get_jiffies_64() % 2)
+ return NULL;
+ return &prog_test_struct;
+}
+
+noinline void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p)
+{
+}
+
+struct prog_test_pass1 {
+ int x0;
+ struct {
+ int x1;
+ struct {
+ int x2;
+ struct {
+ int x3;
+ };
+ };
+ };
+};
+
+struct prog_test_pass2 {
+ int len;
+ short arr1[4];
+ struct {
+ char arr2[4];
+ unsigned long arr3[8];
+ } x;
+};
+
+struct prog_test_fail1 {
+ void *p;
+ int x;
+};
+
+struct prog_test_fail2 {
+ int x8;
+ struct prog_test_pass1 x;
+};
+
+struct prog_test_fail3 {
+ int len;
+ char arr1[2];
+ char arr2[0];
+};
+
+noinline void bpf_kfunc_call_test_pass_ctx(struct __sk_buff *skb)
+{
+}
+
+noinline void bpf_kfunc_call_test_pass1(struct prog_test_pass1 *p)
+{
+}
+
+noinline void bpf_kfunc_call_test_pass2(struct prog_test_pass2 *p)
+{
+}
+
+noinline void bpf_kfunc_call_test_fail1(struct prog_test_fail1 *p)
+{
+}
+
+noinline void bpf_kfunc_call_test_fail2(struct prog_test_fail2 *p)
+{
+}
+
+noinline void bpf_kfunc_call_test_fail3(struct prog_test_fail3 *p)
+{
+}
+
+noinline void bpf_kfunc_call_test_mem_len_pass1(void *mem, int mem__sz)
+{
+}
+
+noinline void bpf_kfunc_call_test_mem_len_fail1(void *mem, int len)
+{
+}
+
+noinline void bpf_kfunc_call_test_mem_len_fail2(u64 *mem, int len)
+{
+}
+
__diag_pop();
ALLOW_ERROR_INJECTION(bpf_modify_return_test, ERRNO);
@@ -241,8 +340,31 @@ BTF_SET_START(test_sk_check_kfunc_ids)
BTF_ID(func, bpf_kfunc_call_test1)
BTF_ID(func, bpf_kfunc_call_test2)
BTF_ID(func, bpf_kfunc_call_test3)
+BTF_ID(func, bpf_kfunc_call_test_acquire)
+BTF_ID(func, bpf_kfunc_call_test_release)
+BTF_ID(func, bpf_kfunc_call_test_pass_ctx)
+BTF_ID(func, bpf_kfunc_call_test_pass1)
+BTF_ID(func, bpf_kfunc_call_test_pass2)
+BTF_ID(func, bpf_kfunc_call_test_fail1)
+BTF_ID(func, bpf_kfunc_call_test_fail2)
+BTF_ID(func, bpf_kfunc_call_test_fail3)
+BTF_ID(func, bpf_kfunc_call_test_mem_len_pass1)
+BTF_ID(func, bpf_kfunc_call_test_mem_len_fail1)
+BTF_ID(func, bpf_kfunc_call_test_mem_len_fail2)
BTF_SET_END(test_sk_check_kfunc_ids)
+BTF_SET_START(test_sk_acquire_kfunc_ids)
+BTF_ID(func, bpf_kfunc_call_test_acquire)
+BTF_SET_END(test_sk_acquire_kfunc_ids)
+
+BTF_SET_START(test_sk_release_kfunc_ids)
+BTF_ID(func, bpf_kfunc_call_test_release)
+BTF_SET_END(test_sk_release_kfunc_ids)
+
+BTF_SET_START(test_sk_ret_null_kfunc_ids)
+BTF_ID(func, bpf_kfunc_call_test_acquire)
+BTF_SET_END(test_sk_ret_null_kfunc_ids)
+
static void *bpf_test_init(const union bpf_attr *kattr, u32 size,
u32 headroom, u32 tailroom)
{
@@ -1063,8 +1185,11 @@ out:
}
static const struct btf_kfunc_id_set bpf_prog_test_kfunc_set = {
- .owner = THIS_MODULE,
- .check_set = &test_sk_check_kfunc_ids,
+ .owner = THIS_MODULE,
+ .check_set = &test_sk_check_kfunc_ids,
+ .acquire_set = &test_sk_acquire_kfunc_ids,
+ .release_set = &test_sk_release_kfunc_ids,
+ .ret_null_set = &test_sk_ret_null_kfunc_ids,
};
static int __init bpf_prog_test_run_init(void)
--- a/tools/testing/selftests/bpf/prog_tests/kfunc_call.c
+++ b/tools/testing/selftests/bpf/prog_tests/kfunc_call.c
@@ -27,6 +27,12 @@ static void test_main(void)
ASSERT_OK(err, "bpf_prog_test_run(test2)");
ASSERT_EQ(retval, 3, "test2-retval");
+ prog_fd = skel->progs.kfunc_call_test_ref_btf_id.prog_fd;
+ err = bpf_prog_test_run(prog_fd, 1, &pkt_v4, sizeof(pkt_v4),
+ NULL, NULL, (__u32 *)&retval, NULL);
+ ASSERT_OK(err, "bpf_prog_test_run(test_ref_btf_id)");
+ ASSERT_EQ(retval, 0, "test_ref_btf_id-retval");
+
kfunc_call_test_lskel__destroy(skel);
}
--- a/tools/testing/selftests/bpf/progs/kfunc_call_test.c
+++ b/tools/testing/selftests/bpf/progs/kfunc_call_test.c
@@ -1,13 +1,20 @@
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2021 Facebook */
-#include <linux/bpf.h>
+#include <vmlinux.h>
#include <bpf/bpf_helpers.h>
-#include "bpf_tcp_helpers.h"
extern int bpf_kfunc_call_test2(struct sock *sk, __u32 a, __u32 b) __ksym;
extern __u64 bpf_kfunc_call_test1(struct sock *sk, __u32 a, __u64 b,
__u32 c, __u64 d) __ksym;
+extern struct prog_test_ref_kfunc *bpf_kfunc_call_test_acquire(unsigned long *sp) __ksym;
+extern void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym;
+extern void bpf_kfunc_call_test_pass_ctx(struct __sk_buff *skb) __ksym;
+extern void bpf_kfunc_call_test_pass1(struct prog_test_pass1 *p) __ksym;
+extern void bpf_kfunc_call_test_pass2(struct prog_test_pass2 *p) __ksym;
+extern void bpf_kfunc_call_test_mem_len_pass1(void *mem, int len) __ksym;
+extern void bpf_kfunc_call_test_mem_len_fail2(__u64 *mem, int len) __ksym;
+
SEC("tc")
int kfunc_call_test2(struct __sk_buff *skb)
{
@@ -44,4 +51,45 @@ int kfunc_call_test1(struct __sk_buff *s
return ret;
}
+SEC("tc")
+int kfunc_call_test_ref_btf_id(struct __sk_buff *skb)
+{
+ struct prog_test_ref_kfunc *pt;
+ unsigned long s = 0;
+ int ret = 0;
+
+ pt = bpf_kfunc_call_test_acquire(&s);
+ if (pt) {
+ if (pt->a != 42 || pt->b != 108)
+ ret = -1;
+ bpf_kfunc_call_test_release(pt);
+ }
+ return ret;
+}
+
+SEC("tc")
+int kfunc_call_test_pass(struct __sk_buff *skb)
+{
+ struct prog_test_pass1 p1 = {};
+ struct prog_test_pass2 p2 = {};
+ short a = 0;
+ __u64 b = 0;
+ long c = 0;
+ char d = 0;
+ int e = 0;
+
+ bpf_kfunc_call_test_pass_ctx(skb);
+ bpf_kfunc_call_test_pass1(&p1);
+ bpf_kfunc_call_test_pass2(&p2);
+
+ bpf_kfunc_call_test_mem_len_pass1(&a, sizeof(a));
+ bpf_kfunc_call_test_mem_len_pass1(&b, sizeof(b));
+ bpf_kfunc_call_test_mem_len_pass1(&c, sizeof(c));
+ bpf_kfunc_call_test_mem_len_pass1(&d, sizeof(d));
+ bpf_kfunc_call_test_mem_len_pass1(&e, sizeof(e));
+ bpf_kfunc_call_test_mem_len_fail2(&b, -1);
+
+ return 0;
+}
+
char _license[] SEC("license") = "GPL";
--- a/tools/testing/selftests/bpf/verifier/calls.c
+++ b/tools/testing/selftests/bpf/verifier/calls.c
@@ -22,6 +22,81 @@
.result = ACCEPT,
},
{
+ "calls: invalid kfunc call: ptr_to_mem to struct with non-scalar",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .result = REJECT,
+ .errstr = "arg#0 pointer type STRUCT prog_test_fail1 must point to scalar",
+ .fixup_kfunc_btf_id = {
+ { "bpf_kfunc_call_test_fail1", 2 },
+ },
+},
+{
+ "calls: invalid kfunc call: ptr_to_mem to struct with nesting depth > 4",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .result = REJECT,
+ .errstr = "max struct nesting depth exceeded\narg#0 pointer type STRUCT prog_test_fail2",
+ .fixup_kfunc_btf_id = {
+ { "bpf_kfunc_call_test_fail2", 2 },
+ },
+},
+{
+ "calls: invalid kfunc call: ptr_to_mem to struct with FAM",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .result = REJECT,
+ .errstr = "arg#0 pointer type STRUCT prog_test_fail3 must point to scalar",
+ .fixup_kfunc_btf_id = {
+ { "bpf_kfunc_call_test_fail3", 2 },
+ },
+},
+{
+ "calls: invalid kfunc call: reg->type != PTR_TO_CTX",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .result = REJECT,
+ .errstr = "arg#0 expected pointer to ctx, but got PTR",
+ .fixup_kfunc_btf_id = {
+ { "bpf_kfunc_call_test_pass_ctx", 2 },
+ },
+},
+{
+ "calls: invalid kfunc call: void * not allowed in func proto without mem size arg",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .result = REJECT,
+ .errstr = "arg#0 pointer type UNKNOWN must point to scalar",
+ .fixup_kfunc_btf_id = {
+ { "bpf_kfunc_call_test_mem_len_fail1", 2 },
+ },
+},
+{
"calls: basic sanity",
.insns = {
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 2),