sysctl_convert_ctx

函数名称：sysctl_convert_ctx_access

函数原型：static u32 sysctl_convert_ctx_access(enum bpf_access_type type, const struct bpf_insn *si, struct bpf_insn *insn_buf, struct bpf_prog *prog, u32 *target_size)

返回类型：u32

参数：

类型	参数	名称
enum bpf_access_type	type
const struct bpf_insn *	si
struct bpf_insn *	insn_buf
struct bpf_prog *	prog
u32 *	target_size

1361

如果type恒等于BPF_WRITE则

1362

treg等于BPF_REG_9

1364

如果 source register 恒等于treg或 dest register 恒等于treg则treg先自减

1366

如果 source register 恒等于treg或 dest register 恒等于treg则treg先自减

1368

insn自加等于Memory store, *(uint *) (dst_reg + off16) = src_reg (double word (64-bit) , dest register , treg, offsetof(structbpf_sysctl_kern, tmp_reg))

1371

insn自加等于Memory load, dst_reg = *(uint *) (src_reg + off16) (BPF_FIELD_SIZEOF(structbpf_sysctl_kern, ppos), treg, dest register , offsetof(structbpf_sysctl_kern, ppos))

1375

insn自加等于Memory store, *(uint *) (dst_reg + off16) = src_reg (BPF_SIZEOF(u32), treg, source register , bpf_ctx_narrow_access_offset(0, sizeof(u32), sizeof(loff_t)))

1379

insn自加等于Memory load, dst_reg = *(uint *) (src_reg + off16) (double word (64-bit) , treg, dest register , offsetof(structbpf_sysctl_kern, tmp_reg))

1382

否则

1383

insn自加等于Memory load, dst_reg = *(uint *) (src_reg + off16) (BPF_FIELD_SIZEOF(structbpf_sysctl_kern, ppos), dest register , source register , offsetof(structbpf_sysctl_kern, ppos))

1387

read_size等于bpf_size_to_bytes(ld/ldx fields ( opcode ))

1388

insn自加等于Memory load, dst_reg = *(uint *) (src_reg + off16) (ld/ldx fields ( opcode ), dest register , dest register , bpf_ctx_narrow_access_offset(0, read_size, sizeof(loff_t)))

1393

target_size等于sizeof(u32)

1394

退出

函数逻辑报告