Commit 8b55572e authored by Kalesh Singh's avatar Kalesh Singh Committed by Steven Rostedt (Google)
Browse files

tracing/selftests: Add tracefs mount options test 

Add a selftest to check that the tracefs gid mount option is applied
correctly.

   ./ftracetest test.d/00basic/mount_options.tc

Use the new readme string "[gid=<gid>] as a requirement and also update
test_ownership.tc requirements to use this.

Cc: Eric Sandeen <sandeen@redhat.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Ali Zahraee <ahzahraee@gmail.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/20241030171928.4168869-4-kaleshsingh@google.com


Signed-off-by: default avatarKalesh Singh <kaleshsingh@google.com>
Signed-off-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
parent fa17cb4b

tools/testing/selftests/ftrace/test.d/00basic/mount_options.tc

0 → 100644
+101 −0
Original line number Diff line number Diff line 
#!/bin/sh

# SPDX-License-Identifier: GPL-2.0

# description: Test tracefs GID mount option

# requires: "[gid=<gid>]":README



fail() {

	local msg="$1"



	echo "FAILED: $msg"

	exit_fail

}



find_alternate_gid() {

	local original_gid="$1"

	tac /etc/group | grep -v ":$original_gid:" | head -1 | cut -d: -f3

}



mount_tracefs_with_options() {

	local mount_point="$1"

	local options="$2"



	mount -t tracefs -o "$options" nodev "$mount_point"



	setup

}



unmount_tracefs() {

	local mount_point="$1"



	# Need to make sure the mount isn't busy so that we can umount it

	(cd $mount_point; finish_ftrace;)



	cleanup

}



create_instance() {

	local mount_point="$1"

	local instance="$mount_point/instances/$(mktemp -u test-XXXXXX)"



	mkdir "$instance"

	echo "$instance"

}



remove_instance() {

	local instance="$1"



	rmdir "$instance"

}



check_gid() {

	local mount_point="$1"

	local expected_gid="$2"



	echo "Checking permission group ..."



	cd "$mount_point"



	for file in "." "events" "events/sched" "events/sched/sched_switch" "events/sched/sched_switch/enable"; do

		local gid=`stat -c "%g" $file`

		if [ "$gid" -ne "$expected_gid" ]; then

			cd - # Return to the previous working directory (tracefs root)

			fail "$(realpath $file): Expected group $expected_gid; Got group $gid"

		fi

	done



	cd - # Return to the previous working directory (tracefs root)

}



test_gid_mount_option() {

	local mount_point=$(get_mount_point)

	local mount_options=$(get_mnt_options "$mount_point")

	local original_group=$(stat -c "%g" .)

	local other_group=$(find_alternate_gid "$original_group")



	# Set up mount options with new GID for testing

	local new_options=`echo "$mount_options" | sed -e "s/gid=[0-9]*/gid=$other_group/"`

	if [ "$new_options" = "$mount_options" ]; then

		new_options="$mount_options,gid=$other_group"

		mount_options="$mount_options,gid=$original_group"

	fi



	# Unmount existing tracefs instance and mount with new GID

	unmount_tracefs "$mount_point"

	mount_tracefs_with_options "$mount_point" "$new_options"



	check_gid "$mount_point" "$other_group"



	# Check that files created after the mount inherit the GID

	local instance=$(create_instance "$mount_point")

	check_gid "$instance" "$other_group"

	remove_instance "$instance"



	# Unmount and remount with the original GID

	unmount_tracefs "$mount_point"

	mount_tracefs_with_options "$mount_point" "$mount_options"

	check_gid "$mount_point" "$original_group"

}



test_gid_mount_option



exit 0

tools/testing/selftests/ftrace/test.d/00basic/test_ownership.tc

+3 −13
Original line number Diff line number Diff line 
#!/bin/sh

# SPDX-License-Identifier: GPL-2.0

# description: Test file and directory ownership changes for eventfs

# requires: "[gid=<gid>]":README



original_group=`stat -c "%g" .`

original_owner=`stat -c "%u" .`



mount_point=`stat -c '%m' .`

local mount_point=$(get_mount_point)



# If stat -c '%m' does not work (e.g. busybox) or failed, try to use the

# current working directory (which should be a tracefs) as the mount point.

if [ ! -d "$mount_point" ]; then

	if mount | grep -qw $PWD ; then

		mount_point=$PWD

	else

		# If PWD doesn't work, that is an environmental problem.

		exit_unresolved

	fi

fi



mount_options=`mount | grep "$mount_point" | sed -e 's/.*(\(.*\)).*/\1/'`

mount_options=$(get_mnt_options "$mount_point")



# find another owner and group that is not the original

other_group=`tac /etc/group | grep -v ":$original_group:" | head -1 | cut -d: -f3`

tools/testing/selftests/ftrace/test.d/functions

+25 −0
Original line number Diff line number Diff line
@@ -193,3 +193,28 @@ ftrace_errlog_check() { # err-prefix command-with-error-pos-by-^ command-file 
    # "  Command: " and "^\n" => 13

    test $(expr 13 + $pos) -eq $N

}



# Helper to get the tracefs mount point

get_mount_point() {

	local mount_point=`stat -c '%m' .`



	# If stat -c '%m' does not work (e.g. busybox) or failed, try to use the

	# current working directory (which should be a tracefs) as the mount point.

	if [ ! -d "$mount_point" ]; then

		if mount | grep -qw "$PWD"; then

			mount_point=$PWD

		else

			# If PWD doesn't work, that is an environmental problem.

			exit_unresolved

		fi

	fi

	echo "$mount_point"

}



# Helper function to retrieve mount options for a given mount point

get_mnt_options() {

	local mnt_point="$1"

	local opts=$(mount | grep -m1 "$mnt_point" | sed -e 's/.*(\(.*\)).*/\1/')



	echo "$opts"

}
 
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