check_btf

函数名称：check_btf_func

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

返回类型：int

参数：

类型	参数	名称
struct bpf_verifier_env *	env
const union bpf_attr *	attr
union bpf_attr __user *	uattr

6710

ret等于If we're handed a bigger struct than we know of, ensure all the unknown bits* are 0 - i.e. new user-space does not rely on any kernel feature extensions* we don't know about yet.* There is a ToCToU between this function call and the following

6711

如果ret则

6712

如果ret恒等于负E2BIG则

6713

verbose(env, "nonzero tailing record in func info")

6717

如果put_user - Write a simple value into user space(min_size, & userspace bpf_func_info size )则ret等于负EFAULT

6720

转到:err_free

6723

如果copy_from_user( & krecord[i], urecord, min_size)则

6724

ret等于负EFAULT

6725

转到:err_free

6729

如果i恒等于0则

6730

如果insn_off则

6731

verbose(env, "nonzero insn_off %u for the first func info record", insn_off)

6734

ret等于负EINVAL

6735

转到:err_free

6737

否则如果insn_off小于等于prev_offset则

6738

verbose(env, "same or smaller insn offset (%u) than previous func info record (%u)", insn_off, prev_offset)

6741

ret等于负EINVAL

6742

转到:err_free

6745

如果 insn idx of function entry point 不等于insn_off则

6746

verbose(env, "func_info BTF section doesn't match subprog layout in BPF program\n")

6747

ret等于负EINVAL

6748

转到:err_free

6752

type等于btf_type_by_id(btf, type_id)

6753

如果非type或BTF_INFO_KIND( "info" bits arrangement * bits 0-15: vlen (e.g. # of struct's members) * bits 16-23: unused * bits 24-27: kind (e.g. int, ptr, array...etc) * bits 28-30: unused * bit 31: kind_flag, currently used by * struct, union and fwd)不等于Function 则

6754

verbose(env, "invalid type id %d in func info", type_id)

6756

ret等于负EINVAL

6757

转到:err_free

6759

prev_offset等于insn_off

6760

urecord加等于urec_size

函数逻辑报告