From patchwork Mon Jul 15 23:01:53 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eduard Zingerman X-Patchwork-Id: 13733942 X-Patchwork-Delegate: bpf@iogearbox.net Received: from mail-pf1-f172.google.com (mail-pf1-f172.google.com [209.85.210.172]) (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 1F9F8143C49 for ; Mon, 15 Jul 2024 23:02:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721084553; cv=none; b=otH3mixhUPcN+gafwehPjsbbaNTXqf0ekg/7PFYIZA+FQrdryr19nesQWIxQTSukE6vQ7GGdswTkBYJI/uTyDf4b9iOq3uscy18jlQM35Tdf39ZY6JJI5ZuHcC7CfC1ENWrnIeIE5rEhqxcX+bzEI97qWLGLsKSe43XcQJldkUA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721084553; c=relaxed/simple; bh=qEWSHaY6YxLBfqtxrK2EEvtoM/35ocsIieGV3/yigcs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=PM6aXYGeSVy5EXqWR669BrXytNQs1hkVsVFqJkPie8gScGZEMNfj80RvY25qrXSB8ORLPLOSilEPetNehR2nB1tCYW0+KvGOhF6bf4jrPyDNdCt5sj3HAwQI5tqSD+TufLrPaKhHY1jsU3yXjfZRzqoZT0YXaCpbuiu6pnIKnmo= 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=cBfaixrp; arc=none smtp.client-ip=209.85.210.172 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="cBfaixrp" Received: by mail-pf1-f172.google.com with SMTP id d2e1a72fcca58-706a1711ee5so3259065b3a.0 for ; Mon, 15 Jul 2024 16:02:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1721084551; x=1721689351; 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=6OS8NdMPZNHGoTxtKNDKNnwmxe8ypUk8+Q4SCQfNAw4=; b=cBfaixrpkFY264zZp1QR7Q3OVMsb6TvQLy4S9blEFsG9LmCGiqrinKI7FZjPyaAWIi OepDkvAMgEPnzdctoHlEkCt2UVJitrB6Y+Awaa93s8asXLhLFzrqhhUTgLAirOiRNt4w 2EMOuxfwXgVk8VC0X/ZeXpCRFPgZjVXb9xYYi66zDGyZcbaAyhN7vQ7Lpp4lVFpoI23n FKC99flC/3VeRz9tV0rYN9iYXOFfg5R7f/k2oaTyWXLYTNezJVW9S82lA6UD+6JAZoLy OBu+BBV9NaktqDWuy4X5MKCKy5xRuxtJZyCYHVCebnlSN7pAFePP0abZ1V5pQAPtxcgB WvHw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1721084551; x=1721689351; 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=6OS8NdMPZNHGoTxtKNDKNnwmxe8ypUk8+Q4SCQfNAw4=; b=GFUVdFyDhjUvT2j9jcKItkSCfKovn6odU5799ftMLs8owJ7zWVTh+KObUyoz8QHd+3 /VyixC+//oOZoj2feEQJk1ASwBfgUv1pZiacLOFfIBgBwu8c+NfB/YM618kGBEbi1NPi 0q/W08ovffD5OP4XwPlCI8/zKF5+tgKjsLUOTw/d6cGlL5A/jFLAmHZKWlQNI5hnbgsO cD/UJFTSZqqAseDIMXPR8l7Qbk5Hrwk9ufODbqMBTYicoE/KFdY0pTfCWz40DT9QqW2U pUfOAOIYzVkZLVHJTDegWx7+YN1UMBrQG+yAQMD2PKhpgRUTFrhCNPTHY2Vxlc+1wtdm 70lQ== X-Gm-Message-State: AOJu0YzupvXsRJDnCP0w3kFvy+YW5nMF1xCjWqPLL9HcHBVYWoGpUB98 MRAaKpodLO5KsQKqngjgxB2rNMfcwhxvPvN7Sw1D53N6kVwnulfpfmci0w== X-Google-Smtp-Source: AGHT+IEDGjLtoxEje4Dh6ZDX+LrG9smbQY6/qt4QvvdfB06GmUS5pKrsvuXNeqRcp9D+Fjkd4CymTw== X-Received: by 2002:a05:6a00:4f85:b0:705:e5da:8293 with SMTP id d2e1a72fcca58-70c1fba11c6mr639165b3a.12.1721084551019; Mon, 15 Jul 2024 16:02:31 -0700 (PDT) Received: from badger.. ([38.34.87.7]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-70b7ecc9d36sm4915344b3a.205.2024.07.15.16.02.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 Jul 2024 16:02:30 -0700 (PDT) From: Eduard Zingerman To: bpf@vger.kernel.org, ast@kernel.org Cc: andrii@kernel.org, daniel@iogearbox.net, martin.lau@linux.dev, kernel-team@fb.com, yonghong.song@linux.dev, jose.marchesi@oracle.com, Eduard Zingerman Subject: [bpf-next v3 04/12] selftests/bpf: extract utility function for BPF disassembly Date: Mon, 15 Jul 2024 16:01:53 -0700 Message-ID: <20240715230201.3901423-5-eddyz87@gmail.com> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240715230201.3901423-1-eddyz87@gmail.com> References: <20240715230201.3901423-1-eddyz87@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net struct bpf_insn *disasm_insn(struct bpf_insn *insn, char *buf, size_t buf_sz); Disassembles instruction 'insn' to a text buffer 'buf'. Removes insn->code hex prefix added by kernel disassembly routine. Returns a pointer to the next instruction (increments insn by either 1 or 2). Acked-by: Andrii Nakryiko Signed-off-by: Eduard Zingerman --- tools/testing/selftests/bpf/Makefile | 1 + tools/testing/selftests/bpf/disasm_helpers.c | 51 +++++++++++++ tools/testing/selftests/bpf/disasm_helpers.h | 12 +++ .../selftests/bpf/prog_tests/ctx_rewrite.c | 74 +++---------------- tools/testing/selftests/bpf/testing_helpers.c | 1 + 5 files changed, 75 insertions(+), 64 deletions(-) create mode 100644 tools/testing/selftests/bpf/disasm_helpers.c create mode 100644 tools/testing/selftests/bpf/disasm_helpers.h diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index dd49c1d23a60..fcacc693ed8a 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -636,6 +636,7 @@ TRUNNER_EXTRA_SOURCES := test_progs.c \ test_loader.c \ xsk.c \ disasm.c \ + disasm_helpers.c \ json_writer.c \ flow_dissector_load.h \ ip_check_defrag_frags.h diff --git a/tools/testing/selftests/bpf/disasm_helpers.c b/tools/testing/selftests/bpf/disasm_helpers.c new file mode 100644 index 000000000000..96b1f2ffe438 --- /dev/null +++ b/tools/testing/selftests/bpf/disasm_helpers.c @@ -0,0 +1,51 @@ +// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) + +#include +#include "disasm.h" + +struct print_insn_context { + char *buf; + size_t sz; +}; + +static void print_insn_cb(void *private_data, const char *fmt, ...) +{ + struct print_insn_context *ctx = private_data; + va_list args; + + va_start(args, fmt); + vsnprintf(ctx->buf, ctx->sz, fmt, args); + va_end(args); +} + +struct bpf_insn *disasm_insn(struct bpf_insn *insn, char *buf, size_t buf_sz) +{ + struct print_insn_context ctx = { + .buf = buf, + .sz = buf_sz, + }; + struct bpf_insn_cbs cbs = { + .cb_print = print_insn_cb, + .private_data = &ctx, + }; + char *tmp, *pfx_end, *sfx_start; + bool double_insn; + int len; + + print_bpf_insn(&cbs, insn, true); + /* We share code with kernel BPF disassembler, it adds '(FF) ' prefix + * for each instruction (FF stands for instruction `code` byte). + * Remove the prefix inplace, and also simplify call instructions. + * E.g.: "(85) call foo#10" -> "call foo". + * Also remove newline in the end (the 'max(strlen(buf) - 1, 0)' thing). + */ + pfx_end = buf + 5; + sfx_start = buf + max((int)strlen(buf) - 1, 0); + if (strncmp(pfx_end, "call ", 5) == 0 && (tmp = strrchr(buf, '#'))) + sfx_start = tmp; + len = sfx_start - pfx_end; + memmove(buf, pfx_end, len); + buf[len] = 0; + double_insn = insn->code == (BPF_LD | BPF_IMM | BPF_DW); + return insn + (double_insn ? 2 : 1); +} diff --git a/tools/testing/selftests/bpf/disasm_helpers.h b/tools/testing/selftests/bpf/disasm_helpers.h new file mode 100644 index 000000000000..7b26cab70099 --- /dev/null +++ b/tools/testing/selftests/bpf/disasm_helpers.h @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ + +#ifndef __DISASM_HELPERS_H +#define __DISASM_HELPERS_H + +#include + +struct bpf_insn; + +struct bpf_insn *disasm_insn(struct bpf_insn *insn, char *buf, size_t buf_sz); + +#endif /* __DISASM_HELPERS_H */ diff --git a/tools/testing/selftests/bpf/prog_tests/ctx_rewrite.c b/tools/testing/selftests/bpf/prog_tests/ctx_rewrite.c index 08b6391f2f56..dd75ccb03770 100644 --- a/tools/testing/selftests/bpf/prog_tests/ctx_rewrite.c +++ b/tools/testing/selftests/bpf/prog_tests/ctx_rewrite.c @@ -10,7 +10,8 @@ #include "bpf/btf.h" #include "bpf_util.h" #include "linux/filter.h" -#include "disasm.h" +#include "linux/kernel.h" +#include "disasm_helpers.h" #define MAX_PROG_TEXT_SZ (32 * 1024) @@ -628,63 +629,6 @@ static bool match_pattern(struct btf *btf, char *pattern, char *text, char *reg_ return false; } -static void print_insn(void *private_data, const char *fmt, ...) -{ - va_list args; - - va_start(args, fmt); - vfprintf((FILE *)private_data, fmt, args); - va_end(args); -} - -/* Disassemble instructions to a stream */ -static void print_xlated(FILE *out, struct bpf_insn *insn, __u32 len) -{ - const struct bpf_insn_cbs cbs = { - .cb_print = print_insn, - .cb_call = NULL, - .cb_imm = NULL, - .private_data = out, - }; - bool double_insn = false; - int i; - - for (i = 0; i < len; i++) { - if (double_insn) { - double_insn = false; - continue; - } - - double_insn = insn[i].code == (BPF_LD | BPF_IMM | BPF_DW); - print_bpf_insn(&cbs, insn + i, true); - } -} - -/* We share code with kernel BPF disassembler, it adds '(FF) ' prefix - * for each instruction (FF stands for instruction `code` byte). - * This function removes the prefix inplace for each line in `str`. - */ -static void remove_insn_prefix(char *str, int size) -{ - const int prefix_size = 5; - - int write_pos = 0, read_pos = prefix_size; - int len = strlen(str); - char c; - - size = min(size, len); - - while (read_pos < size) { - c = str[read_pos++]; - if (c == 0) - break; - str[write_pos++] = c; - if (c == '\n') - read_pos += prefix_size; - } - str[write_pos] = 0; -} - struct prog_info { char *prog_kind; enum bpf_prog_type prog_type; @@ -699,9 +643,10 @@ static void match_program(struct btf *btf, char *reg_map[][2], bool skip_first_insn) { - struct bpf_insn *buf = NULL; + struct bpf_insn *buf = NULL, *insn, *insn_end; int err = 0, prog_fd = 0; FILE *prog_out = NULL; + char insn_buf[64]; char *text = NULL; __u32 cnt = 0; @@ -739,12 +684,13 @@ static void match_program(struct btf *btf, PRINT_FAIL("Can't open memory stream\n"); goto out; } - if (skip_first_insn) - print_xlated(prog_out, buf + 1, cnt - 1); - else - print_xlated(prog_out, buf, cnt); + insn_end = buf + cnt; + insn = buf + (skip_first_insn ? 1 : 0); + while (insn < insn_end) { + insn = disasm_insn(insn, insn_buf, sizeof(insn_buf)); + fprintf(prog_out, "%s\n", insn_buf); + } fclose(prog_out); - remove_insn_prefix(text, MAX_PROG_TEXT_SZ); ASSERT_TRUE(match_pattern(btf, pattern, text, reg_map), pinfo->prog_kind); diff --git a/tools/testing/selftests/bpf/testing_helpers.c b/tools/testing/selftests/bpf/testing_helpers.c index d5379a0e6da8..ac7c66f4fc7b 100644 --- a/tools/testing/selftests/bpf/testing_helpers.c +++ b/tools/testing/selftests/bpf/testing_helpers.c @@ -7,6 +7,7 @@ #include #include #include +#include "disasm.h" #include "test_progs.h" #include "testing_helpers.h" #include