函数逻辑报告

Linux Kernel

v5.5.9

Brick Technologies Co., Ltd

Source Code:kernel\bpf\verifier.c Create Date:2022-07-27 14:19:17
Last Modify:2022-05-19 20:02:10 Copyright©Brick
首页 函数Tree
注解内核,赢得工具下载SCCTEnglish

函数名称：opt_subreg_zext_lo32_rnd_hi32

函数原型：static int opt_subreg_zext_lo32_rnd_hi32(struct bpf_verifier_env *env, const union bpf_attr *attr)

返回类型：int

参数：

类型参数名称
struct bpf_verifier_env *env
const union bpf_attr *attr
8666  struct bpf_insn * patch, zext_patch[2], rnd_hi32_patch[4]
8667  aux等于array of per-insn state
8668  delta等于0, len等于 Number of filter blocks
8669  insns等于insnsi
8673  rnd_hi32等于prog_flags按位与BPF_F_TEST_RND_HI32 is used in BPF_PROG_LOAD command for testing purpose.* Verifier does sub-register def/use analysis and identifies instructions whose* def only matters for low 32-bit, high 32-bit is never referenced later
8674  zext_patch[1]等于Special form of mov32, used for doing explicit zero extension on dst. (0)
8675  rnd_hi32_patch[1]等于ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 (mov reg to reg , Kernel hidden auxiliary/helper register. , 0)
8676  rnd_hi32_patch[2]等于ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 (BPF_LSH, Kernel hidden auxiliary/helper register. , 32)
8677  rnd_hi32_patch[3]等于ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg (BPF_OR, 0, Kernel hidden auxiliary/helper register. )
8678  以i小于len循环
8679  adj_idx等于i加delta
8682  insn等于insns[adj_idx]
8683  如果非 this insn zero extends dst reg 则
8687  如果非rnd_hi32则继续下一循环
8690  code等于 opcode
8691  class等于Instruction classes (code)
8692  如果Return TRUE if INSN doesn't have explicit value define. 则继续下一循环
8699  如果This function is supposed to be used by the following 32-bit optimization* code only. It returns TRUE if the source or destination register operates* on 64-bit, otherwise return FALSE.则
8700  如果class恒等于BPF_LD且BPF BPF_DW 0x18 64-bit (code)恒等于BPF_IMM则i自加
8703  继续下一循环
8707  如果class恒等于BPF_LDX且 pointer type for load/store insns 恒等于g points to bpf_context 则继续下一循环
8711  imm_rnd等于get_random_int()
8712  rnd_hi32_patch[0]等于insn
8713  signed immediate constant 等于imm_rnd
8714  dest register 等于 dest register
8715  patch等于rnd_hi32_patch
8716  patch_len等于4
8717  转到:apply_patch_buffer
8720  如果非Return TRUE if the JIT backend wants verifier to enable sub-register usage* analysis code and wants explicit zero extension inserted by verifier.* Otherwise, return FALSE.则继续下一循环
8723  zext_patch[0]等于insn
8724  dest register 等于 dest register
8725  source register 等于 dest register
8726  patch等于zext_patch
8727  patch_len等于2
8728  apply_patch_buffer :
8729  new_prog等于bpf_patch_insn_data(env, adj_idx, patch, patch_len)
8730  如果非new_prog则返回:负ENOMEM
8732  BPF program being verified 等于new_prog
8733  insns等于insnsi
8734  aux等于array of per-insn state
8735  delta加等于patch_len减1
8738  返回:0
调用者
名称描述
bpf_check