Introduce kernel selftest for new bpf_xdp_adjust_data helper.
Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
---
.../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
