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    SubjectRe: [PATCH] liquidio: replace deprecated strncpy with strscpy
    On Thu, Oct 05, 2023 at 09:55:06PM +0000, Justin Stitt wrote:
    > `strncpy` is deprecated for use on NUL-terminated destination strings
    > [1] and as such we should prefer more robust and less ambiguous string
    > interfaces.
    >
    > NUL-padding is not required as rep_cfg is memset to 0:
    > | memset(&rep_cfg, 0, sizeof(rep_cfg));
    >
    > A suitable replacement is `strscpy` [2] due to the fact that it
    > guarantees NUL-termination on the destination buffer without
    > unnecessarily NUL-padding.
    >
    > Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
    > Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
    > Link: https://github.com/KSPP/linux/issues/90
    > Cc: linux-hardening@vger.kernel.org
    > Signed-off-by: Justin Stitt <justinstitt@google.com>
    > ---
    > Note: build-tested only.
    > ---
    > drivers/net/ethernet/cavium/liquidio/lio_vf_rep.c | 3 ++-
    > 1 file changed, 2 insertions(+), 1 deletion(-)
    >
    > diff --git a/drivers/net/ethernet/cavium/liquidio/lio_vf_rep.c b/drivers/net/ethernet/cavium/liquidio/lio_vf_rep.c
    > index 600de587d7a9..aa6c0dfb6f1c 100644
    > --- a/drivers/net/ethernet/cavium/liquidio/lio_vf_rep.c
    > +++ b/drivers/net/ethernet/cavium/liquidio/lio_vf_rep.c
    > @@ -638,7 +638,8 @@ lio_vf_rep_netdev_event(struct notifier_block *nb,
    > memset(&rep_cfg, 0, sizeof(rep_cfg));
    > rep_cfg.req_type = LIO_VF_REP_REQ_DEVNAME;
    > rep_cfg.ifidx = vf_rep->ifidx;
    > - strncpy(rep_cfg.rep_name.name, ndev->name, LIO_IF_NAME_SIZE);
    > + strscpy(rep_cfg.rep_name.name, ndev->name,
    > + sizeof(rep_cfg.rep_name.name));

    struct lio_vf_rep_req {
    ...
    union {
    struct lio_vf_rep_name {
    char name[LIO_IF_NAME_SIZE];
    } rep_name;

    Yup, sizeof(rep_cfg.rep_name.name) == LIO_IF_NAME_SIZE.

    Reviewed-by: Kees Cook <keescook@chromium.org>
    --
    Kees Cook

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