From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f180.google.com (mail-pf1-f180.google.com [209.85.210.180]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5CF8C26B97D for ; Fri, 19 Sep 2025 18:09:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.180 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758305375; cv=none; b=YQFdyzco6P9cWqo7AuwqEyHQq3BVZeOlM4DzNY+Iul2NX3gp0oENYBVdJpUvy1b0aY3QrZJr4MBpvvpvjUtSTBcYLGaACYXTuwpzPUGqfBJL4RSWImiYVPcJGFM6kWc9y5jIoWSjUEbznnlqxizqyzYJ3Zbt7x5MSKHnoQ1BSd4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758305375; c=relaxed/simple; bh=ebEe9IkyQgkamx37VBlEmeJSVSG9SRHubSWbTb9SAwA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DZ0t1Z6lNJDTfRTXkEKYa17YlyoWKHFGpsxYBf8Cg+0YzQ0tsPDsJXypSbz40tqE+5VAcP54Xt6m2lyVztzoSImJhrtZ36Buh8s7HWULp7P3Rhh8DxK0KX7Ci68YoF5erbfcqVJ1nOrkOymdBo+/y7Y6xsrBi1y9r+eGTnNPSbA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=mtfjOuJt; arc=none smtp.client-ip=209.85.210.180 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="mtfjOuJt" Received: by mail-pf1-f180.google.com with SMTP id d2e1a72fcca58-7728815e639so1801851b3a.1 for ; Fri, 19 Sep 2025 11:09:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1758305373; x=1758910173; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=TAxzi5B6cBNAyJn1tXCxSzkoEcVVhnXO76uSYmveprE=; b=mtfjOuJtE+JHiH7TGEUujA0JVKvnFAgJN6GCgI9IV9iXEHDDIX4nh+9p8vzqTkZQ67 yjwWEJkMrrgSjXe81O1gm0Ty+CxADe3Ox65JXZDeP2Y3XLCRAFuCg5T4DOD5E5jNbW1y eYOVDRS8BRdsp6EJg88P5GCc7awRHLmUVkXP239zQHJr3QkfipKVIhS31JYwqnJYp5z0 8FACCt7qmJNv4SP5l4uM0tNuPXMN2yVIlxc24Jk6P6298wydt+8iG+wOojwS2nEJHbcv 5Ff1uySesMFv9WpARr8l4UbtNNVnOx82659zkrn6CGOc36ULPyzNjHsJPaD9qqA85IDr 9yPQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1758305373; x=1758910173; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=TAxzi5B6cBNAyJn1tXCxSzkoEcVVhnXO76uSYmveprE=; b=cptsi3GE3Zm3SH/qVRnPziLlwDDcdWq/SRXw/CEdeNvVNcd+Qu9XIKeYzNogUcIINb fI36bEvSoXA1dannzU34Hl6tcHgoTUa7t7WMlP9zc+tiQJmCi8DK2ptKB3hanwhaH72D OyCHUB5VAvsDGianiXJFR1WMynDGYVWEBRNXxAhDk7jwwoaRfhrLplDUzNaOMJngmjJm o1OUwSkJHQlLUWFbgNWNiulLpmjaupqAm0xSPXgVY40jeaaJcUzmSlAYeCp4TJZB8+Hu KHOg4TBLtzd6w25xkS2yKhQWIRzD/HMoQAY6aPuNRs0MJlgAd2qJRYBzGlOa37rVfz5l elWQ== X-Gm-Message-State: AOJu0YxtxmxquEIwFq9uOr0mTQucKrEwTPtyZBPfkeZTCyw3L7/pI3HE 8ERZmePEiBcqHWo7XJDZbpj4Yek9lkOxoVeutTJsNaV/GX+zx28tgV4O X-Gm-Gg: ASbGncvRd9ZyLhjesXYHkRMjdfjkDk3Sh1kQ6CQeVz3aGuG3bp+e64YHAX1NJaah51o DBEFR/6BtXiDxWKbMbvbIHPar0wjxjnvHELIt4wYgkfqs6+T4QJcQrxidPFNGt5/ABjAj+UAHfg 1azTQ0Xl+HxIE0FaupbP/Rx1sRFNchRKcN7gOJOzrgcBRid8Vqit9m9IIMwn6MT3PZ+1885/Ppn IUXbgVz94H0CjbE/9lhZFqYx1OndqbUcQOZuj/53cXPM0uqHY1iUBRVWV9F+SzqF9Zmmr8aL339 YMoVsH+0zhp1yOsd2DLnCyVEkxayjAsJK5FANJEbQn6IR/Ac7+TBPhwNOWHPCVUpVTt2iY8gx2l 20ojD/Mpc4SrzI/hnH5BMsmdZ X-Google-Smtp-Source: AGHT+IFpKy03VVXHRFUWA0zTaJ1kiPigY2ZLcQIqACK/zncO6Og/fwFBmlQscPr9TTj099hsmIYa0Q== X-Received: by 2002:a05:6a00:a1c:b0:77c:8354:4e37 with SMTP id d2e1a72fcca58-77e4eeb2d0emr4845587b3a.27.1758305372650; Fri, 19 Sep 2025 11:09:32 -0700 (PDT) Received: from localhost ([2a03:2880:ff:4f::]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-77e20bf07c4sm3417706b3a.70.2025.09.19.11.09.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Sep 2025 11:09:32 -0700 (PDT) From: Amery Hung To: bpf@vger.kernel.org Cc: netdev@vger.kernel.org, alexei.starovoitov@gmail.com, andrii@kernel.org, daniel@iogearbox.net, paul.chaignon@gmail.com, kuba@kernel.org, stfomichev@gmail.com, martin.lau@kernel.org, mohsin.bashr@gmail.com, noren@nvidia.com, dtatulea@nvidia.com, saeedm@nvidia.com, tariqt@nvidia.com, mbloch@nvidia.com, maciej.fijalkowski@intel.com, kernel-team@meta.com Subject: [PATCH bpf-next v4 5/6] selftests/bpf: Test bpf_xdp_pull_data Date: Fri, 19 Sep 2025 11:09:25 -0700 Message-ID: <20250919180926.1760403-6-ameryhung@gmail.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20250919180926.1760403-1-ameryhung@gmail.com> References: <20250919180926.1760403-1-ameryhung@gmail.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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 | 176 ++++++++++++++++++ .../selftests/bpf/progs/test_xdp_pull_data.c | 48 +++++ 2 files changed, 224 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..c16801b73fed --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/xdp_pull_data.c @@ -0,0 +1,176 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include "test_xdp_pull_data.skel.h" + +#define PULL_MAX (1 << 31) +#define PULL_PLUS_ONE (1 << 30) + +#define XDP_PACKET_HEADROOM 256 + +/* Find sizes of struct skb_shared_info and struct xdp_frame so that + * we can calculate the maximum pull lengths for test cases + */ +static int find_xdp_sizes(struct test_xdp_pull_data *skel, int frame_sz) +{ + LIBBPF_OPTS(bpf_test_run_opts, topts); + struct xdp_md ctx = {}; + int prog_fd, err; + __u8 *buf; + + buf = calloc(frame_sz, sizeof(__u8)); + if (!ASSERT_OK_PTR(buf, "calloc buf")) + return -ENOMEM; + + topts.data_in = buf; + topts.data_out = buf; + topts.data_size_in = frame_sz; + topts.data_size_out = frame_sz; + /* Pass a data_end larger than the linear space available to make sure + * bpf_prog_test_run_xdp() will fill the linear data area so that + * xdp_find_data_hard_end can infer the size of struct skb_shared_info + */ + ctx.data_end = frame_sz; + topts.ctx_in = &ctx; + topts.ctx_out = &ctx; + topts.ctx_size_in = sizeof(ctx); + topts.ctx_size_out = sizeof(ctx); + + prog_fd = bpf_program__fd(skel->progs.xdp_find_sizes); + err = bpf_prog_test_run_opts(prog_fd, &topts); + ASSERT_OK(err, "bpf_prog_test_run_opts"); + + free(buf); + + return err; +} + +/* 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 + */ +static void run_test(struct test_xdp_pull_data *skel, int retval, + int frame_sz, int buff_len, int meta_len, int data_len, + int pull_len) +{ + LIBBPF_OPTS(bpf_test_run_opts, topts); + struct xdp_md ctx = {}; + int prog_fd, err; + __u8 *buf; + + buf = calloc(buff_len, sizeof(__u8)); + if (!ASSERT_OK_PTR(buf, "calloc buf")) + return; + + buf[meta_len + 1023] = 0xaa; + buf[meta_len + 1024] = 0xbb; + buf[meta_len + 1025] = 0xcc; + + topts.data_in = buf; + topts.data_out = buf; + topts.data_size_in = buff_len; + topts.data_size_out = buff_len; + ctx.data = meta_len; + ctx.data_end = meta_len + data_len; + topts.ctx_in = &ctx; + topts.ctx_out = &ctx; + topts.ctx_size_in = sizeof(ctx); + topts.ctx_size_out = sizeof(ctx); + + skel->bss->data_len = data_len; + if (pull_len & PULL_MAX) { + int headroom = XDP_PACKET_HEADROOM - meta_len - skel->bss->xdpf_sz; + int tailroom = frame_sz - XDP_PACKET_HEADROOM - + data_len - skel->bss->sinfo_sz; + + pull_len = pull_len & PULL_PLUS_ONE ? 1 : 0; + pull_len += headroom + tailroom + data_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, meta_len + pull_len, "linear data size"); + ASSERT_EQ(topts.data_size_out, buff_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[meta_len + 1023], 0xaa, "data[1023]"); + ASSERT_EQ(buf[meta_len + 1024], 0xbb, "data[1024]"); + ASSERT_EQ(buf[meta_len + 1025], 0xcc, "data[1025]"); +out: + free(buf); +} + +static void test_xdp_pull_data_basic(void) +{ + u32 pg_sz, max_meta_len, max_data_len; + struct test_xdp_pull_data *skel; + + skel = test_xdp_pull_data__open_and_load(); + if (!ASSERT_OK_PTR(skel, "test_xdp_pull_data__open_and_load")) + return; + + pg_sz = sysconf(_SC_PAGE_SIZE); + + if (find_xdp_sizes(skel, pg_sz)) + goto out; + + max_meta_len = XDP_PACKET_HEADROOM - skel->bss->xdpf_sz; + max_data_len = pg_sz - XDP_PACKET_HEADROOM - skel->bss->sinfo_sz; + + /* linear xdp pkt, pull 0 byte */ + run_test(skel, XDP_PASS, pg_sz, 2048, 0, 2048, 2048); + + /* multi-buf pkt, pull results in linear xdp pkt */ + run_test(skel, XDP_PASS, pg_sz, 2048, 0, 1024, 2048); + + /* multi-buf pkt, pull 1 byte to linear data area */ + run_test(skel, XDP_PASS, pg_sz, 9000, 0, 1024, 1025); + + /* multi-buf pkt, pull 0 byte to linear data area */ + run_test(skel, XDP_PASS, pg_sz, 9000, 0, 1025, 1025); + + /* multi-buf pkt, empty linear data area, pull requires memmove */ + run_test(skel, XDP_PASS, pg_sz, 9000, 0, 0, PULL_MAX); + + /* multi-buf pkt, no headroom */ + run_test(skel, XDP_PASS, pg_sz, 9000, max_meta_len, 1024, PULL_MAX); + + /* multi-buf pkt, no tailroom, pull requires memmove */ + run_test(skel, XDP_PASS, pg_sz, 9000, 0, max_data_len, PULL_MAX); + + + /* linear xdp pkt, pull more than total data len */ + run_test(skel, XDP_DROP, pg_sz, 2048, 0, 2048, 2049); + + /* multi-buf pkt with no space left in linear data area */ + run_test(skel, XDP_DROP, pg_sz, 9000, max_meta_len, max_data_len, + PULL_MAX | PULL_PLUS_ONE); + + /* multi-buf pkt, empty linear data area */ + run_test(skel, XDP_DROP, pg_sz, 9000, 0, 0, PULL_MAX | PULL_PLUS_ONE); + + /* multi-buf pkt, no headroom */ + run_test(skel, XDP_DROP, pg_sz, 9000, max_meta_len, 1024, + PULL_MAX | PULL_PLUS_ONE); + + /* multi-buf pkt, no tailroom */ + run_test(skel, XDP_DROP, pg_sz, 9000, 0, max_data_len, + PULL_MAX | PULL_PLUS_ONE); + +out: + 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..dd901bb109b6 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_xdp_pull_data.c @@ -0,0 +1,48 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include "vmlinux.h" +#include + +int xdpf_sz; +int sinfo_sz; +int data_len; +int pull_len; + +#define XDP_PACKET_HEADROOM 256 + +SEC("xdp.frags") +int xdp_find_sizes(struct xdp_md *ctx) +{ + xdpf_sz = sizeof(struct xdp_frame); + sinfo_sz = __PAGE_SIZE - XDP_PACKET_HEADROOM - + (ctx->data_end - ctx->data); + + return XDP_PASS; +} + +SEC("xdp.frags") +int xdp_pull_data_prog(struct xdp_md *ctx) +{ + __u8 *data_end = (void *)(long)ctx->data_end; + __u8 *data = (void *)(long)ctx->data; + __u8 *val_p; + int err; + + if (data_len != data_end - data) + return XDP_DROP; + + err = bpf_xdp_pull_data(ctx, pull_len); + if (err) + return XDP_DROP; + + val_p = (void *)(long)ctx->data + 1024; + if (val_p + 1 > (void *)(long)ctx->data_end) + return XDP_DROP; + + if (*val_p != 0xbb) + return XDP_DROP; + + return XDP_PASS; +} + +char _license[] SEC("license") = "GPL"; -- 2.47.3