On Tue, Nov 20, 2018 at 7:43 AM Lorenz Bauer <lmb@xxxxxxxxxxxxxx> wrote: > > Right now, there is no safe way to use BPF_PROG_TEST_RUN with data_out. > This is because bpf_test_finish copies the output buffer to user space > without checking its size. This can lead to the kernel overwriting > data in user space after the buffer if xdp_adjust_head and friends are > in play. > > Changes in v2: > * Make the syscall return ENOSPC if data_size_out is too small > * Make bpf_prog_test_run return EINVAL if size_out is missing > * Document the new behaviour of data_size_out > > Lorenz Bauer (4): > bpf: respect size hint to BPF_PROG_TEST_RUN if present > tools: sync uapi/linux/bpf.h > libbpf: require size hint in bpf_prog_test_run > selftests: add a test for bpf_prog_test_run output size For the series, if we decided to take this approach rather than amending another field in the uapi as described in https://www.spinics.net/lists/netdev/msg534277.html, then Acked-by: Yonghong Song <yhs@xxxxxx>
