On Mon, May 18, 2020 at 6:08 AM Jesper Dangaard Brouer
<brouer@xxxxxxxxxx> wrote:
>
> Commit bc56c919fce7 ("bpf: Add xdp.frame_sz in bpf_prog_test_run_xdp().")
> recently changed bpf_prog_test_run_xdp() to use larger frames for XDP in
> order to test tail growing frames (via bpf_xdp_adjust_tail) and to have
> memory backing frame better resemble drivers.
>
> The commit contains a bug, as it tries to copy the max data size from
> userspace, instead of the size provided by userspace. This cause XDP
> unit tests to fail sporadically with EFAULT, an unfortunate behavior.
> The fix is to only copy the size specified by userspace.
>
> Fixes: bc56c919fce7 ("bpf: Add xdp.frame_sz in bpf_prog_test_run_xdp().")
> Signed-off-by: Jesper Dangaard Brouer <brouer@xxxxxxxxxx>
> ---
LGTM.
Acked-by: Andrii Nakryiko <andriin@xxxxxx>
> net/bpf/test_run.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
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