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	The bpf_alu_sign_string and bpf_movsx_string introduced in commit
f835bb6222 ("bpf: Add kernel/bpftool asm support for new instructions")
are only used in disasm.c now, change them to static.
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202308050615.wxAn1v2J-lkp@intel.com/
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20230803023128.3753323-1-yangyingliang@huawei.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
		
	
			
		
			
				
	
	
		
			350 lines
		
	
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			350 lines
		
	
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
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/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
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 * Copyright (c) 2016 Facebook
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 */
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#include <linux/bpf.h>
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#include "disasm.h"
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#define __BPF_FUNC_STR_FN(x) [BPF_FUNC_ ## x] = __stringify(bpf_ ## x)
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static const char * const func_id_str[] = {
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	__BPF_FUNC_MAPPER(__BPF_FUNC_STR_FN)
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};
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#undef __BPF_FUNC_STR_FN
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static const char *__func_get_name(const struct bpf_insn_cbs *cbs,
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				   const struct bpf_insn *insn,
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				   char *buff, size_t len)
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{
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	BUILD_BUG_ON(ARRAY_SIZE(func_id_str) != __BPF_FUNC_MAX_ID);
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	if (!insn->src_reg &&
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	    insn->imm >= 0 && insn->imm < __BPF_FUNC_MAX_ID &&
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	    func_id_str[insn->imm])
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		return func_id_str[insn->imm];
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	if (cbs && cbs->cb_call) {
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		const char *res;
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		res = cbs->cb_call(cbs->private_data, insn);
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		if (res)
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			return res;
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	}
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	if (insn->src_reg == BPF_PSEUDO_CALL)
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		snprintf(buff, len, "%+d", insn->imm);
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	else if (insn->src_reg == BPF_PSEUDO_KFUNC_CALL)
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		snprintf(buff, len, "kernel-function");
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	return buff;
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}
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static const char *__func_imm_name(const struct bpf_insn_cbs *cbs,
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				   const struct bpf_insn *insn,
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				   u64 full_imm, char *buff, size_t len)
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{
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	if (cbs && cbs->cb_imm)
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		return cbs->cb_imm(cbs->private_data, insn, full_imm);
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	snprintf(buff, len, "0x%llx", (unsigned long long)full_imm);
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	return buff;
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}
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const char *func_id_name(int id)
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{
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	if (id >= 0 && id < __BPF_FUNC_MAX_ID && func_id_str[id])
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		return func_id_str[id];
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	else
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		return "unknown";
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}
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const char *const bpf_class_string[8] = {
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	[BPF_LD]    = "ld",
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	[BPF_LDX]   = "ldx",
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	[BPF_ST]    = "st",
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	[BPF_STX]   = "stx",
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	[BPF_ALU]   = "alu",
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	[BPF_JMP]   = "jmp",
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	[BPF_JMP32] = "jmp32",
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	[BPF_ALU64] = "alu64",
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};
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const char *const bpf_alu_string[16] = {
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	[BPF_ADD >> 4]  = "+=",
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	[BPF_SUB >> 4]  = "-=",
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	[BPF_MUL >> 4]  = "*=",
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	[BPF_DIV >> 4]  = "/=",
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	[BPF_OR  >> 4]  = "|=",
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	[BPF_AND >> 4]  = "&=",
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	[BPF_LSH >> 4]  = "<<=",
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	[BPF_RSH >> 4]  = ">>=",
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	[BPF_NEG >> 4]  = "neg",
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	[BPF_MOD >> 4]  = "%=",
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	[BPF_XOR >> 4]  = "^=",
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	[BPF_MOV >> 4]  = "=",
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	[BPF_ARSH >> 4] = "s>>=",
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	[BPF_END >> 4]  = "endian",
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};
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static const char *const bpf_alu_sign_string[16] = {
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	[BPF_DIV >> 4]  = "s/=",
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	[BPF_MOD >> 4]  = "s%=",
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};
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static const char *const bpf_movsx_string[4] = {
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	[0] = "(s8)",
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	[1] = "(s16)",
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	[3] = "(s32)",
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};
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static const char *const bpf_atomic_alu_string[16] = {
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	[BPF_ADD >> 4]  = "add",
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	[BPF_AND >> 4]  = "and",
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	[BPF_OR >> 4]  = "or",
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	[BPF_XOR >> 4]  = "xor",
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};
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static const char *const bpf_ldst_string[] = {
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	[BPF_W >> 3]  = "u32",
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	[BPF_H >> 3]  = "u16",
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	[BPF_B >> 3]  = "u8",
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	[BPF_DW >> 3] = "u64",
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};
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static const char *const bpf_ldsx_string[] = {
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	[BPF_W >> 3]  = "s32",
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	[BPF_H >> 3]  = "s16",
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	[BPF_B >> 3]  = "s8",
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};
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static const char *const bpf_jmp_string[16] = {
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	[BPF_JA >> 4]   = "jmp",
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	[BPF_JEQ >> 4]  = "==",
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	[BPF_JGT >> 4]  = ">",
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	[BPF_JLT >> 4]  = "<",
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	[BPF_JGE >> 4]  = ">=",
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	[BPF_JLE >> 4]  = "<=",
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	[BPF_JSET >> 4] = "&",
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	[BPF_JNE >> 4]  = "!=",
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	[BPF_JSGT >> 4] = "s>",
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	[BPF_JSLT >> 4] = "s<",
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	[BPF_JSGE >> 4] = "s>=",
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	[BPF_JSLE >> 4] = "s<=",
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	[BPF_CALL >> 4] = "call",
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	[BPF_EXIT >> 4] = "exit",
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};
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static void print_bpf_end_insn(bpf_insn_print_t verbose,
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			       void *private_data,
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			       const struct bpf_insn *insn)
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{
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	verbose(private_data, "(%02x) r%d = %s%d r%d\n",
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		insn->code, insn->dst_reg,
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		BPF_SRC(insn->code) == BPF_TO_BE ? "be" : "le",
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		insn->imm, insn->dst_reg);
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}
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static void print_bpf_bswap_insn(bpf_insn_print_t verbose,
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			       void *private_data,
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			       const struct bpf_insn *insn)
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{
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	verbose(private_data, "(%02x) r%d = bswap%d r%d\n",
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		insn->code, insn->dst_reg,
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		insn->imm, insn->dst_reg);
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}
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static bool is_sdiv_smod(const struct bpf_insn *insn)
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{
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	return (BPF_OP(insn->code)  == BPF_DIV || BPF_OP(insn->code) == BPF_MOD) &&
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	       insn->off == 1;
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}
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static bool is_movsx(const struct bpf_insn *insn)
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{
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	return BPF_OP(insn->code) == BPF_MOV &&
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	       (insn->off == 8 || insn->off == 16 || insn->off == 32);
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}
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void print_bpf_insn(const struct bpf_insn_cbs *cbs,
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		    const struct bpf_insn *insn,
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		    bool allow_ptr_leaks)
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{
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	const bpf_insn_print_t verbose = cbs->cb_print;
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	u8 class = BPF_CLASS(insn->code);
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	if (class == BPF_ALU || class == BPF_ALU64) {
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		if (BPF_OP(insn->code) == BPF_END) {
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			if (class == BPF_ALU64)
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				print_bpf_bswap_insn(verbose, cbs->private_data, insn);
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			else
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				print_bpf_end_insn(verbose, cbs->private_data, insn);
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		} else if (BPF_OP(insn->code) == BPF_NEG) {
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			verbose(cbs->private_data, "(%02x) %c%d = -%c%d\n",
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				insn->code, class == BPF_ALU ? 'w' : 'r',
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				insn->dst_reg, class == BPF_ALU ? 'w' : 'r',
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				insn->dst_reg);
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		} else if (BPF_SRC(insn->code) == BPF_X) {
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			verbose(cbs->private_data, "(%02x) %c%d %s %s%c%d\n",
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				insn->code, class == BPF_ALU ? 'w' : 'r',
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				insn->dst_reg,
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				is_sdiv_smod(insn) ? bpf_alu_sign_string[BPF_OP(insn->code) >> 4]
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						   : bpf_alu_string[BPF_OP(insn->code) >> 4],
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				is_movsx(insn) ? bpf_movsx_string[(insn->off >> 3) - 1] : "",
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				class == BPF_ALU ? 'w' : 'r',
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				insn->src_reg);
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		} else {
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			verbose(cbs->private_data, "(%02x) %c%d %s %d\n",
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				insn->code, class == BPF_ALU ? 'w' : 'r',
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				insn->dst_reg,
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				is_sdiv_smod(insn) ? bpf_alu_sign_string[BPF_OP(insn->code) >> 4]
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						   : bpf_alu_string[BPF_OP(insn->code) >> 4],
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				insn->imm);
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		}
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	} else if (class == BPF_STX) {
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		if (BPF_MODE(insn->code) == BPF_MEM)
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			verbose(cbs->private_data, "(%02x) *(%s *)(r%d %+d) = r%d\n",
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				insn->code,
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				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
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				insn->dst_reg,
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				insn->off, insn->src_reg);
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		else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
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			 (insn->imm == BPF_ADD || insn->imm == BPF_AND ||
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			  insn->imm == BPF_OR || insn->imm == BPF_XOR)) {
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			verbose(cbs->private_data, "(%02x) lock *(%s *)(r%d %+d) %s r%d\n",
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				insn->code,
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				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
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				insn->dst_reg, insn->off,
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				bpf_alu_string[BPF_OP(insn->imm) >> 4],
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				insn->src_reg);
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		} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
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			   (insn->imm == (BPF_ADD | BPF_FETCH) ||
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			    insn->imm == (BPF_AND | BPF_FETCH) ||
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			    insn->imm == (BPF_OR | BPF_FETCH) ||
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			    insn->imm == (BPF_XOR | BPF_FETCH))) {
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			verbose(cbs->private_data, "(%02x) r%d = atomic%s_fetch_%s((%s *)(r%d %+d), r%d)\n",
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				insn->code, insn->src_reg,
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				BPF_SIZE(insn->code) == BPF_DW ? "64" : "",
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				bpf_atomic_alu_string[BPF_OP(insn->imm) >> 4],
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				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
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				insn->dst_reg, insn->off, insn->src_reg);
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		} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
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			   insn->imm == BPF_CMPXCHG) {
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			verbose(cbs->private_data, "(%02x) r0 = atomic%s_cmpxchg((%s *)(r%d %+d), r0, r%d)\n",
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				insn->code,
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				BPF_SIZE(insn->code) == BPF_DW ? "64" : "",
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				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
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				insn->dst_reg, insn->off,
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				insn->src_reg);
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		} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
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			   insn->imm == BPF_XCHG) {
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			verbose(cbs->private_data, "(%02x) r%d = atomic%s_xchg((%s *)(r%d %+d), r%d)\n",
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				insn->code, insn->src_reg,
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				BPF_SIZE(insn->code) == BPF_DW ? "64" : "",
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				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
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				insn->dst_reg, insn->off, insn->src_reg);
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		} else {
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			verbose(cbs->private_data, "BUG_%02x\n", insn->code);
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		}
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	} else if (class == BPF_ST) {
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		if (BPF_MODE(insn->code) == BPF_MEM) {
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			verbose(cbs->private_data, "(%02x) *(%s *)(r%d %+d) = %d\n",
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				insn->code,
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				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
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				insn->dst_reg,
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				insn->off, insn->imm);
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		} else if (BPF_MODE(insn->code) == 0xc0 /* BPF_NOSPEC, no UAPI */) {
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			verbose(cbs->private_data, "(%02x) nospec\n", insn->code);
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		} else {
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			verbose(cbs->private_data, "BUG_st_%02x\n", insn->code);
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		}
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	} else if (class == BPF_LDX) {
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		if (BPF_MODE(insn->code) != BPF_MEM && BPF_MODE(insn->code) != BPF_MEMSX) {
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			verbose(cbs->private_data, "BUG_ldx_%02x\n", insn->code);
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			return;
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		}
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		verbose(cbs->private_data, "(%02x) r%d = *(%s *)(r%d %+d)\n",
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			insn->code, insn->dst_reg,
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			BPF_MODE(insn->code) == BPF_MEM ?
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				 bpf_ldst_string[BPF_SIZE(insn->code) >> 3] :
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				 bpf_ldsx_string[BPF_SIZE(insn->code) >> 3],
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			insn->src_reg, insn->off);
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	} else if (class == BPF_LD) {
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		if (BPF_MODE(insn->code) == BPF_ABS) {
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			verbose(cbs->private_data, "(%02x) r0 = *(%s *)skb[%d]\n",
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				insn->code,
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				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
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				insn->imm);
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		} else if (BPF_MODE(insn->code) == BPF_IND) {
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			verbose(cbs->private_data, "(%02x) r0 = *(%s *)skb[r%d + %d]\n",
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				insn->code,
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				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
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				insn->src_reg, insn->imm);
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		} else if (BPF_MODE(insn->code) == BPF_IMM &&
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			   BPF_SIZE(insn->code) == BPF_DW) {
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			/* At this point, we already made sure that the second
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			 * part of the ldimm64 insn is accessible.
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			 */
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			u64 imm = ((u64)(insn + 1)->imm << 32) | (u32)insn->imm;
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			bool is_ptr = insn->src_reg == BPF_PSEUDO_MAP_FD ||
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				      insn->src_reg == BPF_PSEUDO_MAP_VALUE;
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			char tmp[64];
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			if (is_ptr && !allow_ptr_leaks)
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				imm = 0;
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			verbose(cbs->private_data, "(%02x) r%d = %s\n",
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				insn->code, insn->dst_reg,
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				__func_imm_name(cbs, insn, imm,
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						tmp, sizeof(tmp)));
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		} else {
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			verbose(cbs->private_data, "BUG_ld_%02x\n", insn->code);
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			return;
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		}
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	} else if (class == BPF_JMP32 || class == BPF_JMP) {
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		u8 opcode = BPF_OP(insn->code);
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		if (opcode == BPF_CALL) {
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			char tmp[64];
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			if (insn->src_reg == BPF_PSEUDO_CALL) {
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				verbose(cbs->private_data, "(%02x) call pc%s\n",
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					insn->code,
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					__func_get_name(cbs, insn,
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							tmp, sizeof(tmp)));
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			} else {
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				strcpy(tmp, "unknown");
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				verbose(cbs->private_data, "(%02x) call %s#%d\n", insn->code,
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					__func_get_name(cbs, insn,
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							tmp, sizeof(tmp)),
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					insn->imm);
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			}
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		} else if (insn->code == (BPF_JMP | BPF_JA)) {
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			verbose(cbs->private_data, "(%02x) goto pc%+d\n",
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				insn->code, insn->off);
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		} else if (insn->code == (BPF_JMP32 | BPF_JA)) {
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			verbose(cbs->private_data, "(%02x) gotol pc%+d\n",
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				insn->code, insn->imm);
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		} else if (insn->code == (BPF_JMP | BPF_EXIT)) {
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			verbose(cbs->private_data, "(%02x) exit\n", insn->code);
 | 
						|
		} else if (BPF_SRC(insn->code) == BPF_X) {
 | 
						|
			verbose(cbs->private_data,
 | 
						|
				"(%02x) if %c%d %s %c%d goto pc%+d\n",
 | 
						|
				insn->code, class == BPF_JMP32 ? 'w' : 'r',
 | 
						|
				insn->dst_reg,
 | 
						|
				bpf_jmp_string[BPF_OP(insn->code) >> 4],
 | 
						|
				class == BPF_JMP32 ? 'w' : 'r',
 | 
						|
				insn->src_reg, insn->off);
 | 
						|
		} else {
 | 
						|
			verbose(cbs->private_data,
 | 
						|
				"(%02x) if %c%d %s 0x%x goto pc%+d\n",
 | 
						|
				insn->code, class == BPF_JMP32 ? 'w' : 'r',
 | 
						|
				insn->dst_reg,
 | 
						|
				bpf_jmp_string[BPF_OP(insn->code) >> 4],
 | 
						|
				insn->imm, insn->off);
 | 
						|
		}
 | 
						|
	} else {
 | 
						|
		verbose(cbs->private_data, "(%02x) %s\n",
 | 
						|
			insn->code, bpf_class_string[class]);
 | 
						|
	}
 | 
						|
}
 |