Test bpf_xdp_pull_data() with xdp packets with different layouts. The xdp bpf program first checks if the layout is as expected. Then, it calls bpf_xdp_pull_data(). Finally, it checks the 0xbb marker at offset 1024 using directly packet access. Signed-off-by: Amery Hung --- .../selftests/bpf/prog_tests/xdp_pull_data.c | 96 +++++++++++++++++++ .../selftests/bpf/progs/test_xdp_pull_data.c | 36 +++++++ 2 files changed, 132 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/xdp_pull_data.c create mode 100644 tools/testing/selftests/bpf/progs/test_xdp_pull_data.c diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_pull_data.c b/tools/testing/selftests/bpf/prog_tests/xdp_pull_data.c new file mode 100644 index 000000000000..2cd18e15d47e --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/xdp_pull_data.c @@ -0,0 +1,96 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include "test_xdp_pull_data.skel.h" + +/* xdp_pull_data_prog will directly read a marker 0xbb stored at buf[1024] + * so caller expecting XDP_PASS should always pass pull_len no less than 1024 + */ +void test_xdp_pull_data_common(struct test_xdp_pull_data *skel, + int buf_len, int linear_len, + int pull_len, int retval) +{ + LIBBPF_OPTS(bpf_test_run_opts, topts); + struct xdp_md ctx = {}; + int prog_fd, err; + __u8 *buf; + + buf = calloc(buf_len, sizeof(__u8)); + if (!ASSERT_OK_PTR(buf, "calloc buf")) + return; + + buf[1023] = 0xaa; + buf[1024] = 0xbb; + buf[1025] = 0xcc; + + topts.data_in = buf; + topts.data_out = buf; + topts.data_size_in = buf_len; + topts.data_size_out = buf_len; + ctx.data_end = linear_len; + topts.ctx_in = &ctx; + topts.ctx_out = &ctx; + topts.ctx_size_in = sizeof(ctx); + topts.ctx_size_out = sizeof(ctx); + + skel->bss->linear_len = linear_len; + skel->bss->pull_len = pull_len; + + prog_fd = bpf_program__fd(skel->progs.xdp_pull_data_prog); + err = bpf_prog_test_run_opts(prog_fd, &topts); + ASSERT_OK(err, "bpf_prog_test_run_opts"); + ASSERT_EQ(topts.retval, retval, "xdp_pull_data_prog retval"); + + if (retval == XDP_DROP) + goto out; + + ASSERT_EQ(ctx.data_end, pull_len, "linear data size"); + ASSERT_EQ(topts.data_size_out, buf_len, "linear + non-linear data size"); + /* Make sure data around xdp->data_end was not messed up by + * bpf_xdp_pull_data() + */ + ASSERT_EQ(buf[1023], 0xaa, "buf[1023]"); + ASSERT_EQ(buf[1024], 0xbb, "buf[1024]"); + ASSERT_EQ(buf[1025], 0xcc, "buf[1025]"); +out: + free(buf); +} + +static void test_xdp_pull_data_basic(void) +{ + struct test_xdp_pull_data *skel; + u32 page_size; + + skel = test_xdp_pull_data__open_and_load(); + if (!ASSERT_OK_PTR(skel, "test_xdp_pull_data__open_and_load")) + return; + + page_size = sysconf(_SC_PAGE_SIZE); + + /* linear xdp pkt, pull 0 byte */ + test_xdp_pull_data_common(skel, 2048, 2048, 2048, XDP_PASS); + /* multi-buf pkt, pull results in linear xdp pkt */ + test_xdp_pull_data_common(skel, 2048, 1024, 2048, XDP_PASS); + /* multi-buf pkt, pull 1 byte to linear data area */ + test_xdp_pull_data_common(skel, 9000, 1024, 1025, XDP_PASS); + /* multi-buf pkt, pull 0 byte to linear data area */ + test_xdp_pull_data_common(skel, 9000, 1025, 1025, XDP_PASS); + + /* linear xdp pkt, pull more than total data len */ + test_xdp_pull_data_common(skel, 2048, 2048, 2049, XDP_DROP); + /* multi-buf pkt with no space left in linear data area. + * Since ctx.data_end (4096) > max_data_sz, bpf_prog_test_run_xdp() + * will fill the whole linear data area and put the reset into a + * fragment. + */ + test_xdp_pull_data_common(skel, page_size, page_size, page_size, XDP_DROP); + + test_xdp_pull_data__destroy(skel); +} + +void test_xdp_pull_data(void) +{ + if (test__start_subtest("xdp_pull_data")) + test_xdp_pull_data_basic(); +} diff --git a/tools/testing/selftests/bpf/progs/test_xdp_pull_data.c b/tools/testing/selftests/bpf/progs/test_xdp_pull_data.c new file mode 100644 index 000000000000..f32e6b4a79f5 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_xdp_pull_data.c @@ -0,0 +1,36 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include "vmlinux.h" +#include + +int _version SEC("version") = 1; + +int linear_len; +int pull_len; + +SEC("xdp.frags") +int xdp_pull_data_prog(struct xdp_md *xdp) +{ + __u8 *data_end = (void *)(long)xdp->data_end; + __u8 *data = (void *)(long)xdp->data; + __u8 *val_p; + int err; + + if (linear_len != data_end - data) + return XDP_DROP; + + err = bpf_xdp_pull_data(xdp, pull_len, 0); + if (err) + return XDP_DROP; + + val_p = (void *)(long)xdp->data + 1024; + if (val_p + 1 > (void *)(long)xdp->data_end) + return XDP_DROP; + + if (*val_p != 0xbb) + return XDP_DROP; + + return XDP_PASS; +} + +char _license[] SEC("license") = "GPL"; -- 2.47.3