This is a note to let you know that I've just added the patch titled
selftest/lkdtm: Skip stack-entropy test if lkdtm is not available
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
selftest-lkdtm-skip-stack-entropy-test-if-lkdtm-is-not-available.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 90091c367e74d5b58d9ebe979cc363f7468f58d3 Mon Sep 17 00:00:00 2001
From: Misono Tomohiro <misono.tomohiro@xxxxxxxxxxxxxx>
Date: Thu, 5 Aug 2021 19:12:36 +0900
Subject: selftest/lkdtm: Skip stack-entropy test if lkdtm is not available
From: Misono Tomohiro <misono.tomohiro@xxxxxxxxxxxxxx>
commit 90091c367e74d5b58d9ebe979cc363f7468f58d3 upstream.
Exit with return code 4 if lkdtm is not available like other tests
in order to properly skip the test.
Signed-off-by: Misono Tomohiro <misono.tomohiro@xxxxxxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20210805101236.1140381-1-misono.tomohiro@xxxxxxxxxxxxxx
Cc: Andrew Paniakin <apanyaki@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
tools/testing/selftests/lkdtm/stack-entropy.sh | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)
--- a/tools/testing/selftests/lkdtm/stack-entropy.sh
+++ b/tools/testing/selftests/lkdtm/stack-entropy.sh
@@ -4,13 +4,27 @@
# Measure kernel stack entropy by sampling via LKDTM's REPORT_STACK test.
set -e
samples="${1:-1000}"
+TRIGGER=/sys/kernel/debug/provoke-crash/DIRECT
+KSELFTEST_SKIP_TEST=4
+
+# Verify we have LKDTM available in the kernel.
+if [ ! -r $TRIGGER ] ; then
+ /sbin/modprobe -q lkdtm || true
+ if [ ! -r $TRIGGER ] ; then
+ echo "Cannot find $TRIGGER (missing CONFIG_LKDTM?)"
+ else
+ echo "Cannot write $TRIGGER (need to run as root?)"
+ fi
+ # Skip this test
+ exit $KSELFTEST_SKIP_TEST
+fi
# Capture dmesg continuously since it may fill up depending on sample size.
log=$(mktemp -t stack-entropy-XXXXXX)
dmesg --follow >"$log" & pid=$!
report=-1
for i in $(seq 1 $samples); do
- echo "REPORT_STACK" >/sys/kernel/debug/provoke-crash/DIRECT
+ echo "REPORT_STACK" > $TRIGGER
if [ -t 1 ]; then
percent=$(( 100 * $i / $samples ))
if [ "$percent" -ne "$report" ]; then
Patches currently in stable-queue which might be from misono.tomohiro@xxxxxxxxxxxxxx are
queue-5.15/selftest-lkdtm-skip-stack-entropy-test-if-lkdtm-is-not-available.patch
