tracing: fprobe-event: Fix to check tracepoint event and return
authorMasami Hiramatsu (Google) <mhiramat@kernel.org>
Wed, 8 Nov 2023 12:12:39 +0000 (21:12 +0900)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 28 Nov 2023 17:20:13 +0000 (17:20 +0000)
commit0e9a6b8a7d88f28c401b2a9413ffd958faf10570
treefae4db2ec6faeb4a46eba9c97af4c2dc2287a0e4
parentcff8bf67f126b1a330ada1a0fd8c98fd69f3cb1c
tracing: fprobe-event: Fix to check tracepoint event and return

commit ce51e6153f7781bcde0f8bb4c81d6fd85ee422e6 upstream.

Fix to check the tracepoint event is not valid with $retval.
The commit 08c9306fc2e3 ("tracing/fprobe-event: Assume fprobe is
a return event by $retval") introduced automatic return probe
conversion with $retval. But since tracepoint event does not
support return probe, $retval is not acceptable.

Without this fix, ftracetest, tprobe_syntax_errors.tc fails;

[22] Tracepoint probe event parser error log check      [FAIL]
 ----
 # tail 22-tprobe_syntax_errors.tc-log.mRKroL
 + ftrace_errlog_check trace_fprobe t kfree ^$retval dynamic_events
 + printf %s t kfree
 + wc -c
 + pos=8
 + printf %s t kfree ^$retval
 + tr -d ^
 + command=t kfree $retval
 + echo Test command: t kfree $retval
 Test command: t kfree $retval
 + echo
 ----

So 't kfree $retval' should fail (tracepoint doesn't support
return probe) but passed it.

Link: https://lore.kernel.org/all/169944555933.45057.12831706585287704173.stgit@devnote2/
Fixes: 08c9306fc2e3 ("tracing/fprobe-event: Assume fprobe is a return event by $retval")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kernel/trace/trace_fprobe.c