Use Source IP condition in IAM policy.
{
"Version": "2012-10-17",
"Statement": [
{
"Sid": "Statement1",
"Effect": "Allow",
"Action": [
"*"
],
"Resource": [
"*"
],
"Condition": {
"IpAddress": {
"aws:SourceIp": [
"202.74.246.XXX/32"
]
}
}
}
]
}