[PATCH net-next 2/2] net: netconsole: selftests: Add userdata validation

[Breno Leitao <leitao@debian.org>]

Extend netcons_basic selftest to verify the userdata functionality by:
 1. Creating a test key in the userdata configfs directory
 2. Writing a known value to the key
 3. Validating the key-value pair appears in the captured network output

This ensures the userdata feature is properly tested during selftests.

Signed-off-by: Breno Leitao <leitao@debian.org>
---
 .../selftests/drivers/net/netcons_basic.sh    | 29 +++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/tools/testing/selftests/drivers/net/netcons_basic.sh b/tools/testing/selftests/drivers/net/netcons_basic.sh
index 4ad1e216c6b0..d182dcc2a10b 100755
--- a/tools/testing/selftests/drivers/net/netcons_basic.sh
+++ b/tools/testing/selftests/drivers/net/netcons_basic.sh
@@ -26,10 +26,13 @@ DSTIP=192.168.2.2
 
 PORT="6666"
 MSG="netconsole selftest"
+USERDATA_KEY="key"
+USERDATA_VALUE="value"
 TARGET=$(mktemp -u netcons_XXXXX)
 DEFAULT_PRINTK_VALUES=$(cat /proc/sys/kernel/printk)
 NETCONS_CONFIGFS="/sys/kernel/config/netconsole"
 NETCONS_PATH="${NETCONS_CONFIGFS}"/"${TARGET}"
+KEY_PATH="${NETCONS_PATH}/userdata/${USERDATA_KEY}"
 # NAMESPACE will be populated by setup_ns with a random value
 NAMESPACE=""
 
@@ -122,6 +125,8 @@ function cleanup() {
 
 	# delete netconsole dynamic reconfiguration
 	echo 0 > "${NETCONS_PATH}"/enabled
+	# Remove key
+	rmdir "${KEY_PATH}"
 	# Remove the configfs entry
 	rmdir "${NETCONS_PATH}"
 
@@ -136,6 +141,18 @@ function cleanup() {
 	echo "${DEFAULT_PRINTK_VALUES}" > /proc/sys/kernel/printk
 }
 
+function set_user_data() {
+	if [[ ! -d "${NETCONS_PATH}""/userdata" ]]
+	then
+		echo "Userdata path not available in ${NETCONS_PATH}/userdata"
+		exit "${ksft_skip}"
+	fi
+
+	mkdir -p "${KEY_PATH}"
+	VALUE_PATH="${KEY_PATH}""/value"
+	echo "${USERDATA_VALUE}" > "${VALUE_PATH}"
+}
+
 function listen_port_and_save_to() {
 	local OUTPUT=${1}
 	# Just wait for 2 seconds
@@ -146,6 +163,10 @@ function listen_port_and_save_to() {
 function validate_result() {
 	local TMPFILENAME="$1"
 
+	# TMPFILENAME will contain something like:
+	# 6.11.1-0_fbk0_rc13_509_g30d75cea12f7,13,1822,115075213798,-;netconsole selftest: netcons_gtJHM
+	#  key=value
+
 	# Check if the file exists
 	if [ ! -f "$TMPFILENAME" ]; then
 		echo "FAIL: File was not generated." >&2
@@ -158,6 +179,12 @@ function validate_result() {
 		exit "${ksft_fail}"
 	fi
 
+	if ! grep -q "${USERDATA_KEY}=${USERDATA_VALUE}" "${TMPFILENAME}"; then
+		echo "FAIL: ${USERDATA_KEY}=${USERDATA_VALUE} not found in ${TMPFILENAME}" >&2
+		cat "${TMPFILENAME}" >&2
+		exit "${ksft_fail}"
+	fi
+
 	# Delete the file once it is validated, otherwise keep it
 	# for debugging purposes
 	rm "${TMPFILENAME}"
@@ -220,6 +247,8 @@ trap cleanup EXIT
 set_network
 # Create a dynamic target for netconsole
 create_dynamic_target
+# Set userdata "key" with the "value" value
+set_user_data
 # Listed for netconsole port inside the namespace and destination interface
 listen_port_and_save_to "${OUTPUT_FILE}" &
 # Wait for socat to start and listen to the port.
-- 
2.43.5