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    SubjectRe: [PATCH] dma-buf: Replace strlcpy() with strscpy()
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    Am 17.11.23 um 19:50 schrieb T.J. Mercier:
    > On Thu, Nov 16, 2023 at 11:14 AM Kees Cook <keescook@chromium.org> wrote:
    >> strlcpy() reads the entire source buffer first. This read may exceed
    >> the destination size limit. This is both inefficient and can lead
    >> to linear read overflows if a source string is not NUL-terminated[1].
    >> Additionally, it returns the size of the source string, not the
    >> resulting size of the destination string. In an effort to remove strlcpy()
    >> completely[2], replace strlcpy() here with strscpy().
    >>
    >> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy [1]
    >> Link: https://github.com/KSPP/linux/issues/89 [2]
    >> Cc: Sumit Semwal <sumit.semwal@linaro.org>
    >> Cc: "Christian König" <christian.koenig@amd.com>
    >> Cc: Azeem Shaikh <azeemshaikh38@gmail.com>
    >> Cc: linux-media@vger.kernel.org
    >> Cc: dri-devel@lists.freedesktop.org
    >> Cc: linaro-mm-sig@lists.linaro.org
    >> Signed-off-by: Kees Cook <keescook@chromium.org>
    > Reviewed-by: T.J. Mercier <tjmercier@google.com>
    >
    > strscpy returns -E2BIG when it truncates / force null-terminates which
    > would provide the wrong argument for dynamic_dname, but
    > dma_buf_set_name{_user} makes sure we have a null-terminated string of
    > the appropriate maximum size in dmabuf->name.

    Thanks for that background check, I was about to note that this might
    not be a good idea.

    Linus pretty clearly stated that he doesn't want to see patches like
    that one here, see this article as well. https://lwn.net/Articles/659214/

    I think the commit message gives enough reason to merge the patch, so
    I'm going to push it to drm-misc-next. But please make sure to triple
    check stuff like this before sending.

    Thanks,
    Christian.

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