WARNING: line length of 81 exceeds 80 columns
#45: FILE: tools/testing/selftests/net/netfilter/nft_nat.sh:879:
+		echo "ERROR: in and output file mismatch when checking $msg" 1>&1

WARNING: line length of 147 exceeds 80 columns
#101: FILE: tools/testing/selftests/net/netfilter/nft_nat.sh:1036:
+		echo "PONG 10.0.1.1 step $i" | ip netns exec "$ns0" timeout 3 socat STDIO UDP4-LISTEN:1234,bind=10.0.1.1 > "$OUTFILE" 2>/dev/null &

WARNING: line length of 125 exceeds 80 columns
#106: FILE: tools/testing/selftests/net/netfilter/nft_nat.sh:1041:
+		result=$(ip netns exec "$ns1" timeout 3 socat STDIO UDP4-SENDTO:"$udpdaddr:1234,sourceport=4321" < "$INFILE")

WARNING: line length of 118 exceeds 80 columns
#110: FILE: tools/testing/selftests/net/netfilter/nft_nat.sh:1045:
+			echo "ERROR: failed to test udp $ns1 to $ns2 with dnat rule step $i, result: \"$result\"" 1>&2

total: 0 errors, 4 warnings, 0 checks, 105 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

Commit 366498afb1fc ("selftests: netfilter: nft_nat.sh: add test for reverse clash with nat") has style problems, please review.

NOTE: Ignored message types: ALLOC_SIZEOF_STRUCT BAD_REPORTED_BY_LINK CAMELCASE COMMIT_LOG_LONG_LINE GIT_COMMIT_ID MACRO_ARG_REUSE NO_AUTHOR_SIGN_OFF

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.
total: 0 errors, 4 warnings, 0 checks, 105 lines checked