From: Joe Stringer <joe@wand.net.nz>
To: daniel@iogearbox.net
Cc: netdev@vger.kernel.org, ast@kernel.org, john.fastabend@gmail.com,
tgraf@suug.ch, kafai@fb.com, nitin.hande@gmail.com,
mauricio.vasquez@polito.it
Subject: [PATCHv4 bpf-next 12/13] selftests/bpf: Add C tests for reference tracking
Date: Tue, 2 Oct 2018 13:35:40 -0700 [thread overview]
Message-ID: <20181002203541.26599-13-joe@wand.net.nz> (raw)
In-Reply-To: <20181002203541.26599-1-joe@wand.net.nz>
Add some tests that demonstrate and test the balanced lookup/free
nature of socket lookup. Section names that start with "fail" represent
programs that are expected to fail verification; all others should
succeed.
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
v3: Rebase against flags arg change of bpf_sk_release()
New tests:
* "fail_use_after_free"
* "fail_modify_sk_pointer"
* "fail_modify_sk_or_null_pointer"
v4: No change.
---
tools/testing/selftests/bpf/Makefile | 2 +-
tools/testing/selftests/bpf/test_progs.c | 38 ++++
.../selftests/bpf/test_sk_lookup_kern.c | 180 ++++++++++++++++++
3 files changed, 219 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/test_sk_lookup_kern.c
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index f802de526f57..1381ab81099c 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -36,7 +36,7 @@ TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test
test_get_stack_rawtp.o test_sockmap_kern.o test_sockhash_kern.o \
test_lwt_seg6local.o sendmsg4_prog.o sendmsg6_prog.o test_lirc_mode2_kern.o \
get_cgroup_id_kern.o socket_cookie_prog.o test_select_reuseport_kern.o \
- test_skb_cgroup_id_kern.o bpf_flow.o netcnt_prog.o
+ test_skb_cgroup_id_kern.o bpf_flow.o netcnt_prog.o test_sk_lookup_kern.o
# Order correspond to 'make run_tests' order
TEST_PROGS := test_kmod.sh \
diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c
index 63a671803ed6..e8becca9c521 100644
--- a/tools/testing/selftests/bpf/test_progs.c
+++ b/tools/testing/selftests/bpf/test_progs.c
@@ -1698,6 +1698,43 @@ static void test_task_fd_query_tp(void)
"sys_enter_read");
}
+static void test_reference_tracking()
+{
+ const char *file = "./test_sk_lookup_kern.o";
+ struct bpf_object *obj;
+ struct bpf_program *prog;
+ __u32 duration;
+ int err = 0;
+
+ obj = bpf_object__open(file);
+ if (IS_ERR(obj)) {
+ error_cnt++;
+ return;
+ }
+
+ bpf_object__for_each_program(prog, obj) {
+ const char *title;
+
+ /* Ignore .text sections */
+ title = bpf_program__title(prog, false);
+ if (strstr(title, ".text") != NULL)
+ continue;
+
+ bpf_program__set_type(prog, BPF_PROG_TYPE_SCHED_CLS);
+
+ /* Expect verifier failure if test name has 'fail' */
+ if (strstr(title, "fail") != NULL) {
+ libbpf_set_print(NULL, NULL, NULL);
+ err = !bpf_program__load(prog, "GPL", 0);
+ libbpf_set_print(printf, printf, NULL);
+ } else {
+ err = bpf_program__load(prog, "GPL", 0);
+ }
+ CHECK(err, title, "\n");
+ }
+ bpf_object__close(obj);
+}
+
int main(void)
{
jit_enabled = is_jit_enabled();
@@ -1719,6 +1756,7 @@ int main(void)
test_get_stack_raw_tp();
test_task_fd_query_rawtp();
test_task_fd_query_tp();
+ test_reference_tracking();
printf("Summary: %d PASSED, %d FAILED\n", pass_cnt, error_cnt);
return error_cnt ? EXIT_FAILURE : EXIT_SUCCESS;
diff --git a/tools/testing/selftests/bpf/test_sk_lookup_kern.c b/tools/testing/selftests/bpf/test_sk_lookup_kern.c
new file mode 100644
index 000000000000..b745bdc08c2b
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_sk_lookup_kern.c
@@ -0,0 +1,180 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+// Copyright (c) 2018 Covalent IO, Inc. http://covalent.io
+
+#include <stddef.h>
+#include <stdbool.h>
+#include <string.h>
+#include <linux/bpf.h>
+#include <linux/if_ether.h>
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/pkt_cls.h>
+#include <linux/tcp.h>
+#include <sys/socket.h>
+#include "bpf_helpers.h"
+#include "bpf_endian.h"
+
+int _version SEC("version") = 1;
+char _license[] SEC("license") = "GPL";
+
+/* Fill 'tuple' with L3 info, and attempt to find L4. On fail, return NULL. */
+static struct bpf_sock_tuple *get_tuple(void *data, __u64 nh_off,
+ void *data_end, __u16 eth_proto,
+ bool *ipv4)
+{
+ struct bpf_sock_tuple *result;
+ __u8 proto = 0;
+ __u64 ihl_len;
+
+ if (eth_proto == bpf_htons(ETH_P_IP)) {
+ struct iphdr *iph = (struct iphdr *)(data + nh_off);
+
+ if (iph + 1 > data_end)
+ return NULL;
+ ihl_len = iph->ihl * 4;
+ proto = iph->protocol;
+ *ipv4 = true;
+ result = (struct bpf_sock_tuple *)&iph->saddr;
+ } else if (eth_proto == bpf_htons(ETH_P_IPV6)) {
+ struct ipv6hdr *ip6h = (struct ipv6hdr *)(data + nh_off);
+
+ if (ip6h + 1 > data_end)
+ return NULL;
+ ihl_len = sizeof(*ip6h);
+ proto = ip6h->nexthdr;
+ *ipv4 = true;
+ result = (struct bpf_sock_tuple *)&ip6h->saddr;
+ }
+
+ if (data + nh_off + ihl_len > data_end || proto != IPPROTO_TCP)
+ return NULL;
+
+ return result;
+}
+
+SEC("sk_lookup_success")
+int bpf_sk_lookup_test0(struct __sk_buff *skb)
+{
+ void *data_end = (void *)(long)skb->data_end;
+ void *data = (void *)(long)skb->data;
+ struct ethhdr *eth = (struct ethhdr *)(data);
+ struct bpf_sock_tuple *tuple;
+ struct bpf_sock *sk;
+ size_t tuple_len;
+ bool ipv4;
+
+ if (eth + 1 > data_end)
+ return TC_ACT_SHOT;
+
+ tuple = get_tuple(data, sizeof(*eth), data_end, eth->h_proto, &ipv4);
+ if (!tuple || tuple + sizeof *tuple > data_end)
+ return TC_ACT_SHOT;
+
+ tuple_len = ipv4 ? sizeof(tuple->ipv4) : sizeof(tuple->ipv6);
+ sk = bpf_sk_lookup_tcp(skb, tuple, tuple_len, 0, 0);
+ if (sk)
+ bpf_sk_release(sk);
+ return sk ? TC_ACT_OK : TC_ACT_UNSPEC;
+}
+
+SEC("sk_lookup_success_simple")
+int bpf_sk_lookup_test1(struct __sk_buff *skb)
+{
+ struct bpf_sock_tuple tuple = {};
+ struct bpf_sock *sk;
+
+ sk = bpf_sk_lookup_tcp(skb, &tuple, sizeof(tuple), 0, 0);
+ if (sk)
+ bpf_sk_release(sk);
+ return 0;
+}
+
+SEC("fail_use_after_free")
+int bpf_sk_lookup_uaf(struct __sk_buff *skb)
+{
+ struct bpf_sock_tuple tuple = {};
+ struct bpf_sock *sk;
+ __u32 family = 0;
+
+ sk = bpf_sk_lookup_tcp(skb, &tuple, sizeof(tuple), 0, 0);
+ if (sk) {
+ bpf_sk_release(sk);
+ family = sk->family;
+ }
+ return family;
+}
+
+SEC("fail_modify_sk_pointer")
+int bpf_sk_lookup_modptr(struct __sk_buff *skb)
+{
+ struct bpf_sock_tuple tuple = {};
+ struct bpf_sock *sk;
+ __u32 family;
+
+ sk = bpf_sk_lookup_tcp(skb, &tuple, sizeof(tuple), 0, 0);
+ if (sk) {
+ sk += 1;
+ bpf_sk_release(sk);
+ }
+ return 0;
+}
+
+SEC("fail_modify_sk_or_null_pointer")
+int bpf_sk_lookup_modptr_or_null(struct __sk_buff *skb)
+{
+ struct bpf_sock_tuple tuple = {};
+ struct bpf_sock *sk;
+ __u32 family;
+
+ sk = bpf_sk_lookup_tcp(skb, &tuple, sizeof(tuple), 0, 0);
+ sk += 1;
+ if (sk)
+ bpf_sk_release(sk);
+ return 0;
+}
+
+SEC("fail_no_release")
+int bpf_sk_lookup_test2(struct __sk_buff *skb)
+{
+ struct bpf_sock_tuple tuple = {};
+
+ bpf_sk_lookup_tcp(skb, &tuple, sizeof(tuple), 0, 0);
+ return 0;
+}
+
+SEC("fail_release_twice")
+int bpf_sk_lookup_test3(struct __sk_buff *skb)
+{
+ struct bpf_sock_tuple tuple = {};
+ struct bpf_sock *sk;
+
+ sk = bpf_sk_lookup_tcp(skb, &tuple, sizeof(tuple), 0, 0);
+ bpf_sk_release(sk);
+ bpf_sk_release(sk);
+ return 0;
+}
+
+SEC("fail_release_unchecked")
+int bpf_sk_lookup_test4(struct __sk_buff *skb)
+{
+ struct bpf_sock_tuple tuple = {};
+ struct bpf_sock *sk;
+
+ sk = bpf_sk_lookup_tcp(skb, &tuple, sizeof(tuple), 0, 0);
+ bpf_sk_release(sk);
+ return 0;
+}
+
+void lookup_no_release(struct __sk_buff *skb)
+{
+ struct bpf_sock_tuple tuple = {};
+ bpf_sk_lookup_tcp(skb, &tuple, sizeof(tuple), 0, 0);
+}
+
+SEC("fail_no_release_subcall")
+int bpf_sk_lookup_test5(struct __sk_buff *skb)
+{
+ lookup_no_release(skb);
+ return 0;
+}
--
2.17.1
next prev parent reply other threads:[~2018-10-03 3:21 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-02 20:35 [PATCHv4 bpf-next 00/13] Add socket lookup support Joe Stringer
2018-10-02 20:35 ` [PATCHv4 bpf-next 01/13] bpf: Add iterator for spilled registers Joe Stringer
2018-10-02 20:35 ` [PATCHv4 bpf-next 02/13] bpf: Simplify ptr_min_max_vals adjustment Joe Stringer
2018-10-02 20:35 ` [PATCHv4 bpf-next 03/13] bpf: Reuse canonical string formatter for ctx errs Joe Stringer
2018-10-02 20:35 ` [PATCHv4 bpf-next 04/13] bpf: Generalize ptr_or_null regs check Joe Stringer
2018-10-02 20:35 ` [PATCHv4 bpf-next 05/13] bpf: Add PTR_TO_SOCKET verifier type Joe Stringer
2018-10-02 20:35 ` [PATCHv4 bpf-next 06/13] bpf: Macrofy stack state copy Joe Stringer
2018-10-02 20:35 ` [PATCHv4 bpf-next 07/13] bpf: Add reference tracking to verifier Joe Stringer
2019-01-09 5:27 ` Alexei Starovoitov
2019-01-10 19:26 ` Joe Stringer
2018-10-02 20:35 ` [PATCHv4 bpf-next 08/13] bpf: Add helper to retrieve socket in BPF Joe Stringer
2018-10-02 20:35 ` [PATCHv4 bpf-next 09/13] selftests/bpf: Generalize dummy program types Joe Stringer
2018-10-02 20:35 ` [PATCHv4 bpf-next 10/13] selftests/bpf: Add tests for reference tracking Joe Stringer
2018-10-02 20:35 ` [PATCHv4 bpf-next 11/13] libbpf: Support loading individual progs Joe Stringer
2018-10-02 20:35 ` Joe Stringer [this message]
2018-10-02 20:35 ` [PATCHv4 bpf-next 13/13] Documentation: Describe bpf reference tracking Joe Stringer
2018-10-03 1:08 ` [PATCHv4 bpf-next 00/13] Add socket lookup support Daniel Borkmann
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