[PATCH v13 bpf-next 18/18] bpf: add bpf_xdp_adjust_data selftest
From: Lorenzo Bianconi <lorenzo@kernel.org>
Date: 2021-09-07 12:37:25
Also in:
bpf
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [selftests] (test runners & infrastructure), kernel selftest framework, the rest, xdp (express data path) · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Shuah Khan, Shuah Khan, Linus Torvalds, David S. Miller, Jakub Kicinski, Jesper Dangaard Brouer, John Fastabend
Introduce kernel selftest for new bpf_xdp_adjust_data helper. Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> --- .../bpf/prog_tests/xdp_adjust_data.c | 63 +++++++++++++++++++ .../bpf/progs/test_xdp_update_frags.c | 45 +++++++++++++ 2 files changed, 108 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/xdp_adjust_data.c create mode 100644 tools/testing/selftests/bpf/progs/test_xdp_update_frags.c
diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_adjust_data.c b/tools/testing/selftests/bpf/prog_tests/xdp_adjust_data.c
new file mode 100644
index 000000000000..dfb8bce8ff55
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/xdp_adjust_data.c@@ -0,0 +1,63 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <test_progs.h> +#include <network_helpers.h> + +void test_xdp_update_frag(void) +{ + const char *file = "./test_xdp_update_frags.o"; + __u32 duration, retval, size; + struct bpf_object *obj; + int err, prog_fd; + __u32 *offset; + __u8 *buf; + + err = bpf_prog_load(file, BPF_PROG_TYPE_XDP, &obj, &prog_fd); + if (CHECK_FAIL(err)) + return; + + buf = malloc(128); + if (CHECK(!buf, "malloc()", "error:%s\n", strerror(errno))) + return; + + memset(buf, 0, 128); + offset = (__u32 *)buf; + *offset = 16; + buf[*offset] = 0xaa; /* marker at offset 16 */ + + err = bpf_prog_test_run(prog_fd, 1, buf, 128, + buf, &size, &retval, &duration); + + /* test_xdp_update_frags: buf[16]: 0xaa -> 0xbb */ + CHECK(err || retval != XDP_PASS || buf[16] != 0xbb, + "128b", "err %d errno %d retval %d size %d\n", + err, errno, retval, size); + + free(buf); + + buf = malloc(9000); + if (CHECK(!buf, "malloc()", "error:%s\n", strerror(errno))) + return; + + memset(buf, 0, 9000); + offset = (__u32 *)buf; + *offset = 5000; + buf[*offset] = 0xaa; /* marker at offset 5000 (frag0) */ + + err = bpf_prog_test_run(prog_fd, 1, buf, 9000, + buf, &size, &retval, &duration); + + /* test_xdp_update_frags: buf[5000]: 0xaa -> 0xbb */ + CHECK(err || retval != XDP_PASS || buf[5000] != 0xbb, + "9000b", "err %d errno %d retval %d size %d\n", + err, errno, retval, size); + + free(buf); + + bpf_object__close(obj); +} + +void test_xdp_adjust_data(void) +{ + if (test__start_subtest("xdp_adjust_data")) + test_xdp_update_frag(); +}
diff --git a/tools/testing/selftests/bpf/progs/test_xdp_update_frags.c b/tools/testing/selftests/bpf/progs/test_xdp_update_frags.c
new file mode 100644
index 000000000000..d06504228265
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_xdp_update_frags.c@@ -0,0 +1,45 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + */ +#include <linux/bpf.h> +#include <linux/if_ether.h> +#include <bpf/bpf_helpers.h> + +int _version SEC("version") = 1; + +SEC("xdp_adjust_frags") +int _xdp_adjust_frags(struct xdp_md *xdp) +{ + __u8 *data_end = (void *)(long)xdp->data_end; + __u8 *data = (void *)(long)xdp->data; + int base_offset, ret = XDP_DROP; + __u32 offset; + + if (data + sizeof(__u32) > data_end) + return XDP_DROP; + + offset = *(__u32 *)data; + base_offset = bpf_xdp_adjust_data(xdp, offset); + if (base_offset < 0 || base_offset > offset) + return XDP_DROP; + + data_end = (void *)(long)xdp->data_end; + data = (void *)(long)xdp->data; + + if (data + 1 > data_end) + goto out; + + if (*data != 0xaa) /* marker */ + goto out; + + *data = 0xbb; /* update the marker */ + ret = XDP_PASS; +out: + bpf_xdp_adjust_data(xdp, 0); + return ret; +} + +char _license[] SEC("license") = "GPL";
--
2.31.1