In /logs/firmware/unblob_extracted/firmware_extract/56048-12514271.gzip_extract/gzip.uncompressed_extract/5243916-15068666.gzip_extract/gzip.uncompressed_extract/etc/network/if-pre-up.d/wait_iface line 7:

if [ "${IF_WAIT_DELAY}" -a ! -e "/sys/class/net/${IFACE}" ]; then

                        ^-- SC2166 (warning): Prefer [ p ] && [ q ] as [ p -a q ] is not well defined.

In /logs/firmware/unblob_extracted/firmware_extract/56048-12514271.gzip_extract/gzip.uncompressed_extract/5243916-15068666.gzip_extract/gzip.uncompressed_extract/etc/network/if-pre-up.d/wait_iface line 9:

    while [ ${IF_WAIT_DELAY} -gt 0 ]; do

            ^--------------^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 

    while [ "${IF_WAIT_DELAY}" -gt 0 ]; do

For more information:

  https://www.shellcheck.net/wiki/SC2166 -- Prefer [ p ] && [ q ] as [ p -a q...

  https://www.shellcheck.net/wiki/SC2086 -- Double quote to prevent globbing ...