On 11/23, Yonghong Song wrote:
On 11/23/22 4:23 AM, Jiri Olsa wrote:
> On Mon, Nov 21, 2022 at 10:03:40AM -0800, Stanislav Fomichev wrote:
> > LWT_XMIT to test L3 case, TC to test L2 case.
> >
> > v2:
> > - s/veth_ifindex/ipip_ifindex/ in two places (Martin)
> > - add comment about which condition triggers the rejection (Martin)
> >
> > Signed-off-by: Stanislav Fomichev <sdf@xxxxxxxxxx>
>
> hi,
> I'm getting selftest fails and it looks like it's because of this test:
>
> [root@qemu bpf]# ./test_progs -n 62,98
> #62 empty_skb:OK
> execute_one_variant:PASS:skel_open 0 nsec
> execute_one_variant:PASS:my_pid_map_update 0 nsec
> libbpf: failed to determine tracepoint 'raw_syscalls/sys_enter' perf
event ID: No such file or directory
> libbpf: prog 'handle_legacy': failed to create
tracepoint 'raw_syscalls/sys_enter' perf event: No such file or directory
> libbpf: prog 'handle_legacy': failed to auto-attach: -2
> execute_one_variant:FAIL:skel_attach unexpected error: -2 (errno 2)
> test_legacy_printk:FAIL:legacy_case unexpected error: -2 (errno 2)
> execute_one_variant:PASS:skel_open 0 nsec
> libbpf: failed to determine tracepoint 'raw_syscalls/sys_enter' perf
event ID: No such file or directory
> libbpf: prog 'handle_modern': failed to create
tracepoint 'raw_syscalls/sys_enter' perf event: No such file or directory
> libbpf: prog 'handle_modern': failed to auto-attach: -2
> execute_one_variant:FAIL:skel_attach unexpected error: -2 (errno 2)
> #98 legacy_printk:FAIL
>
> All error logs:
> execute_one_variant:PASS:skel_open 0 nsec
> execute_one_variant:PASS:my_pid_map_update 0 nsec
> libbpf: failed to determine tracepoint 'raw_syscalls/sys_enter' perf
event ID: No such file or directory
> libbpf: prog 'handle_legacy': failed to create
tracepoint 'raw_syscalls/sys_enter' perf event: No such file or directory
> libbpf: prog 'handle_legacy': failed to auto-attach: -2
> execute_one_variant:FAIL:skel_attach unexpected error: -2 (errno 2)
> test_legacy_printk:FAIL:legacy_case unexpected error: -2 (errno 2)
> execute_one_variant:PASS:skel_open 0 nsec
> libbpf: failed to determine tracepoint 'raw_syscalls/sys_enter' perf
event ID: No such file or directory
> libbpf: prog 'handle_modern': failed to create
tracepoint 'raw_syscalls/sys_enter' perf event: No such file or directory
> libbpf: prog 'handle_modern': failed to auto-attach: -2
> execute_one_variant:FAIL:skel_attach unexpected error: -2 (errno 2)
> #98 legacy_printk:FAIL
> Summary: 1/0 PASSED, 0 SKIPPED, 1 FAILED
>
> when I run separately it passes:
>
> [root@qemu bpf]# ./test_progs -n 98
> #98 legacy_printk:OK
> Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED
>
>
> it seems that the open_netns/close_netns does not work properly,
> and screw up access to tracefs for following tests
>
> if I comment out all the umounts in setns_by_fd, it does not fail
Agreed with the above observations.
With the current bpf-next, I can easily hit the above perf event ID issue.
But if I backout the following two patches:
68f8e3d4b916531ea3bb8b83e35138cf78f2fce5 selftests/bpf: Make sure zero-len
skbs aren't redirectable
114039b342014680911c35bd6b72624180fd669a bpf: Move skb->len == 0 checks
into
__bpf_redirect
and run a few times with './test_progs -j' and I didn't hit any issues.
My guess would be that we need to remount debugfs in setns_by_fd?
diff --git a/tools/testing/selftests/bpf/network_helpers.c
b/tools/testing/selftests/bpf/network_helpers.c
index bec15558fd93..1f37adff7632 100644
--- a/tools/testing/selftests/bpf/network_helpers.c
+++ b/tools/testing/selftests/bpf/network_helpers.c
@@ -426,6 +426,10 @@ static int setns_by_fd(int nsfd)
if (!ASSERT_OK(err, "mount /sys/fs/bpf"))
return err;
+ err = mount("debugfs", "/sys/kernel/debug", "debugfs", 0, NULL);
+ if (!ASSERT_OK(err, "mount /sys/kernel/debug"))
+ return err;
+
return 0;
}
>
> jirka
>
>
> > ---
> > .../selftests/bpf/prog_tests/empty_skb.c | 146
++++++++++++++++++
> > tools/testing/selftests/bpf/progs/empty_skb.c | 37 +++++
> > 2 files changed, 183 insertions(+)
> > create mode 100644
tools/testing/selftests/bpf/prog_tests/empty_skb.c
> > create mode 100644 tools/testing/selftests/bpf/progs/empty_skb.c
> >
> > diff --git a/tools/testing/selftests/bpf/prog_tests/empty_skb.c
b/tools/testing/selftests/bpf/prog_tests/empty_skb.c
> > new file mode 100644
> > index 000000000000..32dd731e9070
> > --- /dev/null
> > +++ b/tools/testing/selftests/bpf/prog_tests/empty_skb.c
> > @@ -0,0 +1,146 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +#include <test_progs.h>
> > +#include <network_helpers.h>
> > +#include <net/if.h>
> > +#include "empty_skb.skel.h"
> > +
> > +#define SYS(cmd) ({ \
> > + if (!ASSERT_OK(system(cmd), (cmd))) \
> > + goto out; \
> > +})
> > +
> > +void test_empty_skb(void)
> > +{
> > + LIBBPF_OPTS(bpf_test_run_opts, tattr);
> > + struct empty_skb *bpf_obj = NULL;
> > + struct nstoken *tok = NULL;
> > + struct bpf_program *prog;
> > + char eth_hlen_pp[15];
> > + char eth_hlen[14];
> > + int veth_ifindex;
> > + int ipip_ifindex;
> > + int err;
> > + int i;
> > +
> > + struct {
> > + const char *msg;
> > + const void *data_in;
> > + __u32 data_size_in;
> > + int *ifindex;
> > + int err;
> > + int ret;
> > + bool success_on_tc;
> > + } tests[] = {
> > + /* Empty packets are always rejected. */
> > +
> > + {
> > + /* BPF_PROG_RUN ETH_HLEN size check */
> > + .msg = "veth empty ingress packet",
> > + .data_in = NULL,
> > + .data_size_in = 0,
> > + .ifindex = &veth_ifindex,
> > + .err = -EINVAL,
> > + },
> > + {
> > + /* BPF_PROG_RUN ETH_HLEN size check */
> > + .msg = "ipip empty ingress packet",
> > + .data_in = NULL,
> > + .data_size_in = 0,
> > + .ifindex = &ipip_ifindex,
> > + .err = -EINVAL,
> > + },
> > +
> > + /* ETH_HLEN-sized packets:
> > + * - can not be redirected at LWT_XMIT
> > + * - can be redirected at TC to non-tunneling dest
> > + */
> > +
> > + {
> > + /* __bpf_redirect_common */
> > + .msg = "veth ETH_HLEN packet ingress",
> > + .data_in = eth_hlen,
> > + .data_size_in = sizeof(eth_hlen),
> > + .ifindex = &veth_ifindex,
> > + .ret = -ERANGE,
> > + .success_on_tc = true,
> > + },
> > + {
> > + /* __bpf_redirect_no_mac
> > + *
> > + * lwt: skb->len=0 <= skb_network_offset=0
> > + * tc: skb->len=14 <= skb_network_offset=14
> > + */
> > + .msg = "ipip ETH_HLEN packet ingress",
> > + .data_in = eth_hlen,
> > + .data_size_in = sizeof(eth_hlen),
> > + .ifindex = &ipip_ifindex,
> > + .ret = -ERANGE,
> > + },
> > +
> > + /* ETH_HLEN+1-sized packet should be redirected. */
> > +
> > + {
> > + .msg = "veth ETH_HLEN+1 packet ingress",
> > + .data_in = eth_hlen_pp,
> > + .data_size_in = sizeof(eth_hlen_pp),
> > + .ifindex = &veth_ifindex,
> > + },
> > + {
> > + .msg = "ipip ETH_HLEN+1 packet ingress",
> > + .data_in = eth_hlen_pp,
> > + .data_size_in = sizeof(eth_hlen_pp),
> > + .ifindex = &ipip_ifindex,
> > + },
> > + };
> > +
> > + SYS("ip netns add empty_skb");
> > + tok = open_netns("empty_skb");
> > + SYS("ip link add veth0 type veth peer veth1");
> > + SYS("ip link set dev veth0 up");
> > + SYS("ip link set dev veth1 up");
> > + SYS("ip addr add 10.0.0.1/8 dev veth0");
> > + SYS("ip addr add 10.0.0.2/8 dev veth1");
> > + veth_ifindex = if_nametoindex("veth0");
> > +
> > + SYS("ip link add ipip0 type ipip local 10.0.0.1 remote 10.0.0.2");
> > + SYS("ip link set ipip0 up");
> > + SYS("ip addr add 192.168.1.1/16 dev ipip0");
> > + ipip_ifindex = if_nametoindex("ipip0");
> > +
> > + bpf_obj = empty_skb__open_and_load();
> > + if (!ASSERT_OK_PTR(bpf_obj, "open skeleton"))
> > + goto out;
> > +
> > + for (i = 0; i < ARRAY_SIZE(tests); i++) {
> > + bpf_object__for_each_program(prog, bpf_obj->obj) {
> > + char buf[128];
> > + bool at_tc = !strncmp(bpf_program__section_name(prog), "tc", 2);
> > +
> > + tattr.data_in = tests[i].data_in;
> > + tattr.data_size_in = tests[i].data_size_in;
> > +
> > + tattr.data_size_out = 0;
> > + bpf_obj->bss->ifindex = *tests[i].ifindex;
> > + bpf_obj->bss->ret = 0;
> > + err = bpf_prog_test_run_opts(bpf_program__fd(prog), &tattr);
> > + sprintf(buf, "err: %s [%s]", tests[i].msg,
bpf_program__name(prog));
> > +
> > + if (at_tc && tests[i].success_on_tc)
> > + ASSERT_GE(err, 0, buf);
> > + else
> > + ASSERT_EQ(err, tests[i].err, buf);
> > + sprintf(buf, "ret: %s [%s]", tests[i].msg,
bpf_program__name(prog));
> > + if (at_tc && tests[i].success_on_tc)
> > + ASSERT_GE(bpf_obj->bss->ret, 0, buf);
> > + else
> > + ASSERT_EQ(bpf_obj->bss->ret, tests[i].ret, buf);
> > + }
> > + }
> > +
> > +out:
> > + if (bpf_obj)
> > + empty_skb__destroy(bpf_obj);
> > + if (tok)
> > + close_netns(tok);
> > + system("ip netns del empty_skb");
> > +}
> > diff --git a/tools/testing/selftests/bpf/progs/empty_skb.c
b/tools/testing/selftests/bpf/progs/empty_skb.c
> > new file mode 100644
> > index 000000000000..4b0cd6753251
> > --- /dev/null
> > +++ b/tools/testing/selftests/bpf/progs/empty_skb.c
> > @@ -0,0 +1,37 @@
> > +// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
> > +#include <linux/bpf.h>
> > +#include <bpf/bpf_helpers.h>
> > +#include <bpf/bpf_endian.h>
> > +
> > +char _license[] SEC("license") = "GPL";
> > +
> > +int ifindex;
> > +int ret;
> > +
> > +SEC("lwt_xmit")
> > +int redirect_ingress(struct __sk_buff *skb)
> > +{
> > + ret = bpf_clone_redirect(skb, ifindex, BPF_F_INGRESS);
> > + return 0;
> > +}
> > +
> > +SEC("lwt_xmit")
> > +int redirect_egress(struct __sk_buff *skb)
> > +{
> > + ret = bpf_clone_redirect(skb, ifindex, 0);
> > + return 0;
> > +}
> > +
> > +SEC("tc")
> > +int tc_redirect_ingress(struct __sk_buff *skb)
> > +{
> > + ret = bpf_clone_redirect(skb, ifindex, BPF_F_INGRESS);
> > + return 0;
> > +}
> > +
> > +SEC("tc")
> > +int tc_redirect_egress(struct __sk_buff *skb)
> > +{
> > + ret = bpf_clone_redirect(skb, ifindex, 0);
> > + return 0;
> > +}
> > --
> > 2.38.1.584.g0f3c55d4c2-goog
> >
