Re: [PATCH net v3 2/2] bpf: selftests: send packet to devmap redirect XDP

Florian Kauer florian.kauer@linutronix.de writes:

The current xdp_devmap_attach test attaches a program that redirects to another program via devmap.

It is, however, never executed, so do that to catch any bugs that might occur during execution.

Also, execute the same for a veth pair so that we also cover the non-generic path.

Warning: Running this without the bugfix in this series will likely crash your system.

Signed-off-by: Florian Kauer florian.kauer@linutronix.de

.../selftests/bpf/prog_tests/xdp_devmap_attach.c | 114 +++++++++++++++++++-- 1 file changed, 108 insertions(+), 6 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_devmap_attach.c b/tools/testing/selftests/bpf/prog_tests/xdp_devmap_attach.c index ce6812558287..3da45f719736 100644 --- a/tools/testing/selftests/bpf/prog_tests/xdp_devmap_attach.c +++ b/tools/testing/selftests/bpf/prog_tests/xdp_devmap_attach.c @@ -1,6 +1,9 @@ // SPDX-License-Identifier: GPL-2.0 +#include <arpa/inet.h> #include <uapi/linux/bpf.h> #include <linux/if_link.h> +#include <network_helpers.h> +#include <net/if.h> #include <test_progs.h> #include "test_xdp_devmap_helpers.skel.h" @@ -17,7 +20,7 @@ static void test_xdp_with_devmap_helpers(void) .ifindex = IFINDEX_LO, }; __u32 len = sizeof(info);

• int err, dm_fd, map_fd;

• int err, dm_fd, dm_fd_redir, map_fd; __u32 idx = 0;

@@ -25,14 +28,11 @@ static void test_xdp_with_devmap_helpers(void) if (!ASSERT_OK_PTR(skel, "test_xdp_with_devmap_helpers__open_and_load")) return;

• dm_fd = bpf_program__fd(skel->progs.xdp_redir_prog);
• err = bpf_xdp_attach(IFINDEX_LO, dm_fd, XDP_FLAGS_SKB_MODE, NULL);

• dm_fd_redir = bpf_program__fd(skel->progs.xdp_redir_prog);
• err = bpf_xdp_attach(IFINDEX_LO, dm_fd_redir, XDP_FLAGS_SKB_MODE, NULL); if (!ASSERT_OK(err, "Generic attach of program with 8-byte devmap")) goto out_close;

• err = bpf_xdp_detach(IFINDEX_LO, XDP_FLAGS_SKB_MODE, NULL);
• ASSERT_OK(err, "XDP program detach");
• dm_fd = bpf_program__fd(skel->progs.xdp_dummy_dm); map_fd = bpf_map__fd(skel->maps.dm_ports); err = bpf_prog_get_info_by_fd(dm_fd, &info, &len);

@@ -47,6 +47,23 @@ static void test_xdp_with_devmap_helpers(void) ASSERT_OK(err, "Read devmap entry"); ASSERT_EQ(info.id, val.bpf_prog.id, "Match program id to devmap entry prog_id");

• /* send a packet to trigger any potential bugs in there */
• char data[10] = {};
• DECLARE_LIBBPF_OPTS(bpf_test_run_opts, opts,

• 	    .data_in = &data,
  

• 	    .data_size_in = 10,
  

• 	    .flags = BPF_F_TEST_XDP_LIVE_FRAMES,
  

• 	    .repeat = 1,
  

• );
  

• err = bpf_prog_test_run_opts(dm_fd_redir, &opts);
• ASSERT_OK(err, "XDP test run");
• /* wait for the packets to be flushed */
• kern_sync_rcu();
• err = bpf_xdp_detach(IFINDEX_LO, XDP_FLAGS_SKB_MODE, NULL);
• ASSERT_OK(err, "XDP program detach");
• /* can not attach BPF_XDP_DEVMAP program to a device */ err = bpf_xdp_attach(IFINDEX_LO, dm_fd, XDP_FLAGS_SKB_MODE, NULL); if (!ASSERT_NEQ(err, 0, "Attach of BPF_XDP_DEVMAP program"))

@@ -124,6 +141,88 @@ static void test_xdp_with_devmap_frags_helpers(void) test_xdp_with_devmap_frags_helpers__destroy(skel); } +static void test_xdp_with_devmap_helpers_veth(void) +{

• struct test_xdp_with_devmap_helpers *skel = NULL;
• struct bpf_prog_info info = {};
• struct bpf_devmap_val val = {};
• struct nstoken *nstoken = NULL;
• __u32 len = sizeof(info);
• int err, dm_fd, dm_fd_redir, map_fd, ifindex_dst;
• __u32 idx = 0;
• SYS(out_close, "ip netns add testns");
• nstoken = open_netns("testns");
• if (!ASSERT_OK_PTR(nstoken, "setns"))

• goto out_close;
  

• SYS(out_close, "ip link add veth_src type veth peer name veth_dst");
• SYS(out_close, "ip link set dev veth_src up");
• SYS(out_close, "ip link set dev veth_dst up");
• val.ifindex = if_nametoindex("veth_src");
• ifindex_dst = if_nametoindex("veth_dst");
• if (!ASSERT_NEQ(val.ifindex, 0, "val.ifindex") ||

•    !ASSERT_NEQ(ifindex_dst, 0, "ifindex_dst"))
  

• goto out_close;
  

• skel = test_xdp_with_devmap_helpers__open_and_load();
• if (!ASSERT_OK_PTR(skel, "test_xdp_with_devmap_helpers__open_and_load"))

• return;
  

This should be 'goto out_close'.

-Toke