[PATCH v3 6/6] ima/ima_violations: Temporarily remove the printk rate limit

[Jia Zhang <zhang.jia@xxxxxxxxxxxxxxxxx>]

The output frequency of audit log is limited by printk_ratelimit()
in kernel if auditd not used. Thus, the test cases heavily depending
on searching certain keywords in log file may fail if the matching
patterns are exactly suppressed by printk_ratelimit().

In order to fix such a sort of failure, just temporarily remove the
printk rate limit, and restore its original setting when doing
cleanup.

Signed-off-by: Jia Zhang <zhang.jia@xxxxxxxxxxxxxxxxx>
---
 .../kernel/security/integrity/ima/tests/ima_setup.sh      |  2 +-
 .../kernel/security/integrity/ima/tests/ima_violations.sh | 15 +++++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/testcases/kernel/security/integrity/ima/tests/ima_setup.sh b/testcases/kernel/security/integrity/ima/tests/ima_setup.sh
index 6dfb4d2..fe60981 100644
--- a/testcases/kernel/security/integrity/ima/tests/ima_setup.sh
+++ b/testcases/kernel/security/integrity/ima/tests/ima_setup.sh
@@ -20,7 +20,7 @@
 TST_TESTFUNC="test"
 TST_SETUP_CALLER="$TST_SETUP"
 TST_SETUP="ima_setup"
-TST_CLEANUP="ima_cleanup"
+TST_CLEANUP="${TST_CLEANUP:-ima_cleanup}"
 TST_NEEDS_TMPDIR=1
 TST_NEEDS_ROOT=1
 
diff --git a/testcases/kernel/security/integrity/ima/tests/ima_violations.sh b/testcases/kernel/security/integrity/ima/tests/ima_violations.sh
index f3f40d4..74223c2 100755
--- a/testcases/kernel/security/integrity/ima/tests/ima_violations.sh
+++ b/testcases/kernel/security/integrity/ima/tests/ima_violations.sh
@@ -20,6 +20,7 @@
 # Test whether ToMToU and open_writer violations invalidatethe PCR and are logged.
 
 TST_SETUP="setup"
+TST_CLEANUP="cleanup"
 TST_CNT=3
 TST_NEEDS_DEVICE=1
 
@@ -31,15 +32,29 @@ setup()
 	FILE="test.txt"
 	IMA_VIOLATIONS="$SECURITYFS/ima/violations"
 	LOG="/var/log/messages"
+	PRINTK_RATE_LIMIT="0"
 
 	if status_daemon auditd; then
 		LOG="/var/log/audit/audit.log"
+	else
+		tst_check_cmds sysctl
+
+		PRINTK_RATE_LIMIT=`sysctl -n kernel.printk_ratelimit`
+		sysctl -wq kernel.printk_ratelimit=0
 	fi
 	[ -f "$LOG" ] || \
 		tst_brk TBROK "log $LOG does not exist (bug in detection?)"
 	tst_res TINFO "using log $LOG"
 }
 
+cleanup()
+{
+	[ "$PRINTK_RATE_LIMIT" != "0" ] && \
+		sysctl -wq kernel.printk_ratelimit=$PRINTK_RATE_LIMIT
+
+	ima_cleanup
+}
+
 open_file_read()
 {
 	exec 3< $FILE || exit 1
-- 
1.8.3.1