[PATCH v2] tracing: selftests: Add testing a user string to filters

[PATCH v2] tracing: selftests: Add testing a user string to filters

[Steven Rostedt]

From: Steven Rostedt <rostedt@goodmis.org>

Running the following commands was broken:

  # cd /sys/kernel/tracing
  # echo "filename.ustring ~ \"/proc*\"" > events/syscalls/sys_enter_openat/filter
  # echo 1 > events/syscalls/sys_enter_openat/enable
  # ls /proc/$$/maps
  # cat trace

And would produce nothing when it should have produced something like:

      ls-1192    [007] .....  8169.828333: sys_openat(dfd: ffffffffffffff9c, filename: 7efc18359904, flags: 80000, mode: 0)

Add a test to check this case so that it will be caught if it breaks
again.

Link: https://lore.kernel.org/linux-trace-kernel/20250417183003.505835fb@gandalf.local.home/

Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
Changes since v1: https://lore.kernel.org/20250417223323.3edb4f6c@batman.local.home

- Use $TMPDIR instead of $TESTDIR as test file (Masami Hiramatsu)

 .../test.d/filter/event-filter-function.tc    | 20 +++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc
index 118247b8dd84..c62165fabd0c 100644
--- a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc
+++ b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc
@@ -80,6 +80,26 @@ if [ $misscnt -gt 0 ]; then
 	exit_fail
 fi
 
+# Check strings too
+if [ -f events/syscalls/sys_enter_openat/filter ]; then
+	DIRNAME=`basename $TMPDIR`
+	echo "filename.ustring ~ \"*$DIRNAME*\"" > events/syscalls/sys_enter_openat/filter
+	echo 1 > events/syscalls/sys_enter_openat/enable
+	echo 1 > tracing_on
+	ls /bin/sh
+	nocnt=`grep openat trace | wc -l`
+	ls $TMPDIR
+	echo 0 > tracing_on
+	hitcnt=`grep openat trace | wc -l`;
+	echo 0 > events/syscalls/sys_enter_openat/enable
+	if [ $nocnt -gt 0 ]; then
+		exit_fail
+	fi
+	if [ $hitcnt -eq 0 ]; then
+		exit_fail
+	fi
+fi
+
 reset_events_filter
 
 exit 0
-- 
2.47.2

Re: [PATCH v2] tracing: selftests: Add testing a user string to filters

[Shuah Khan]

On 4/18/25 08:12, Steven Rostedt wrote:
> From: Steven Rostedt <rostedt@goodmis.org>
> 
> Running the following commands was broken:
> 
>    # cd /sys/kernel/tracing
>    # echo "filename.ustring ~ \"/proc*\"" > events/syscalls/sys_enter_openat/filter
>    # echo 1 > events/syscalls/sys_enter_openat/enable
>    # ls /proc/$$/maps
>    # cat trace
> 
> And would produce nothing when it should have produced something like:
> 
>        ls-1192    [007] .....  8169.828333: sys_openat(dfd: ffffffffffffff9c, filename: 7efc18359904, flags: 80000, mode: 0)
> 
> Add a test to check this case so that it will be caught if it breaks
> again.
> 
> Link: https://lore.kernel.org/linux-trace-kernel/20250417183003.505835fb@gandalf.local.home/
> 
> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
> ---
> Changes since v1: https://lore.kernel.org/20250417223323.3edb4f6c@batman.local.home
> 
> - Use $TMPDIR instead of $TESTDIR as test file (Masami Hiramatsu)
> 

Steve, Masami

Do you want me to take this for rc4?

thanks,
-- Shuah

Re: [PATCH v2] tracing: selftests: Add testing a user string to filters

[Steven Rostedt]

On Tue, 22 Apr 2025 10:59:03 -0600
Shuah Khan <skhan@linuxfoundation.org> wrote:

> > Link: https://lore.kernel.org/linux-trace-kernel/20250417183003.505835fb@gandalf.local.home/
> > 
> > Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
> > ---
> > Changes since v1: https://lore.kernel.org/20250417223323.3edb4f6c@batman.local.home
> > 
> > - Use $TMPDIR instead of $TESTDIR as test file (Masami Hiramatsu)
> >   
> 
> Steve, Masami
> 
> Do you want me to take this for rc4?

Hi Shuah,

Sorry, I didn't copy the comment from v1 to v2, but it still applies:

    Shuah, I'm Cc'ing you on this for your information, but I'll take it
    through my tree as it will be attached with the fix, as it will fail
    without it.

It's already been accepted.

Thanks,

-- Steve