linux/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_user.tc

#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
# description: Kprobe event user-memory access
# requires: kprobe_events '$arg<N>':README

grep -A10 "fetcharg:" README | grep -q 'ustring' || exit_unsupported
grep -A10 "fetcharg:" README | grep -q '\[u\]<offset>' || exit_unsupported

:;: "user-memory access syntax and ustring working on user memory";:
echo 'p:myevent do_sys_open path=+0($arg2):ustring path2=+u0($arg2):string' \
	> kprobe_events
echo 'p:myevent2 do_sys_openat2 path=+0($arg2):ustring path2=+u0($arg2):string' \
	>> kprobe_events

grep myevent kprobe_events | \
	grep -q 'path=+0($arg2):ustring path2=+u0($arg2):string'
echo 1 > events/kprobes/myevent/enable
echo 1 > events/kprobes/myevent2/enable
echo > /dev/null
echo 0 > events/kprobes/myevent/enable
echo 0 > events/kprobes/myevent2/enable

grep myevent trace | grep -q 'path="/dev/null" path2="/dev/null"'

:;: "user-memory access syntax and ustring not working with kernel memory";:
echo 'p:myevent vfs_symlink path=+0($arg3):ustring path2=+u0($arg3):string' \
	> kprobe_events
echo 1 > events/kprobes/myevent/enable
ln -s foo $TMPDIR/bar
echo 0 > events/kprobes/myevent/enable

grep myevent trace | grep -q 'path=(fault) path2=(fault)'

exit 0