On 9/9/20 3:49 PM, Kees Cook wrote:
On Fri, Jun 26, 2020 at 01:59:43PM -0700, Kees Cook wrote:
Instead of full GNU diff (which smaller boot environments may not have),
use "comm" which is more available.
Reported-by: Naresh Kamboju <naresh.kamboju@xxxxxxxxxx>
Link: https://lore.kernel.org/lkml/CA+G9fYtHP+Gg+BrR_GkBMxu2oOi-_e9pATtpb6TVRswv1G1r1Q@xxxxxxxxxxxxxx
Fixes: f131d9edc29d ("selftests/lkdtm: Don't clear dmesg when running tests")
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Shuah, this really needs to land to fix lkdtm tests on busybox. Can
you add this to -next? (Or is it better to direct this to Greg for the
lkdtm tree?)
Thanks!
-Kees
---
tools/testing/selftests/lkdtm/run.sh | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/testing/selftests/lkdtm/run.sh b/tools/testing/selftests/lkdtm/run.sh
index 8383eb89d88a..5fe23009ae13 100755
--- a/tools/testing/selftests/lkdtm/run.sh
+++ b/tools/testing/selftests/lkdtm/run.sh
@@ -82,7 +82,7 @@ dmesg > "$DMESG"
($SHELL -c 'cat <(echo '"$test"') >'"$TRIGGER" 2>/dev/null) || true
# Record and dump the results
-dmesg | diff --changed-group-format='%>' --unchanged-group-format='' "$DMESG" - > "$LOG" || true
+dmesg | comm -13 "$DMESG" - > "$LOG" || true
cat "$LOG"
# Check for expected output
--
2.25.1
--
Kees Cook
Hi Kees,
You may want to consider a similar follow up to the one Miroslav made to
the livepatching equivalent:
https://lore.kernel.org/live-patching/nycvar.YFH.7.76.2008271528000.27422@xxxxxxxxxxxxx/T/#m1c17812d2c005dd57e9a299a4a492026a156619e
basically 'comm' will complain if two lines from dmesg have the same
timestamp prefix and their text portions are not sorted.
Regards,
-- Joe
