Failed to run the elf file after change capability

[fripSide]

Hi, after change the capability, I cannot execute the binary anymore.
It seems that we cannot set the capabiltities lager than the bash and init process of the docker?
Does anything go wrong?

Here is my detailed operations.
Change the capability of the elf for dockerfile:

FROM ubuntu:20.04

RUN mkdir -p /work/
COPY setcap /bin/
COPY getcap /bin/
COPY elf_test /work/
WORKDIR /work/
RUN setcap cap_sys_admin+ep elf_test 

Run the docker:

docker build -t dev:v1 .
docker run --rm -it --name dev_test dev:v1 bash 
root@9156b2c0ce2d:/work# getcap elf_test
elf_test = cap_sys_admin+ep
root@9156b2c0ce2d:/work# ./elf_test
bash: ./elf_test: Operation not permitted