Re: [PATCH v2 0/4] Fix unsafe BPF_PROG_TEST_RUN interface
On Tue, Nov 20, 2018 at 7:43 AM Lorenz Bauer 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
[PATCH v2 0/4] Fix unsafe BPF_PROG_TEST_RUN interface
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 include/uapi/linux/bpf.h | 7 ++-- net/bpf/test_run.c | 15 ++-- tools/include/uapi/linux/bpf.h | 7 ++-- tools/lib/bpf/bpf.c | 7 +++- tools/testing/selftests/bpf/test_progs.c | 44 5 files changed, 73 insertions(+), 7 deletions(-) -- 2.17.1
