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libbpf: Use OPTS_SET() macro in bpf_xdp_query()

Viktor Malik requested to merge vmalikrh/centos-stream-9:libbpf-xdp-query-fix into main

JIRA: https://issues.redhat.com/browse/RHEL-24445

commit 92a871ab9fa59a74d013bc04f321026a057618e7
Author: Toke Høiland-Jørgensen <toke@redhat.com>
Date:   Tue Feb 6 13:59:22 2024 +0100

    libbpf: Use OPTS_SET() macro in bpf_xdp_query()

    When the feature_flags and xdp_zc_max_segs fields were added to the libbpf
    bpf_xdp_query_opts, the code writing them did not use the OPTS_SET() macro.
    This causes libbpf to write to those fields unconditionally, which means
    that programs compiled against an older version of libbpf (with a smaller
    size of the bpf_xdp_query_opts struct) will have its stack corrupted by
    libbpf writing out of bounds.

    The patch adding the feature_flags field has an early bail out if the
    feature_flags field is not part of the opts struct (via the OPTS_HAS)
    macro, but the patch adding xdp_zc_max_segs does not. For consistency, this
    fix just changes the assignments to both fields to use the OPTS_SET()
    macro.

    Fixes: 13ce2daa259a ("xsk: add new netlink attribute dedicated for ZC max frags")
    Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
    Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
    Link: https://lore.kernel.org/bpf/20240206125922.1992815-1-toke@redhat.com

Signed-off-by: Viktor Malik vmalik@redhat.com

Edited by Viktor Malik

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