From 0e9a6b8a7d88f28c401b2a9413ffd958faf10570 Mon Sep 17 00:00:00 2001 From: "Masami Hiramatsu (Google)" Date: Wed, 8 Nov 2023 21:12:39 +0900 Subject: [PATCH] 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 $retval") Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Greg Kroah-Hartman --- kernel/trace/trace_fprobe.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c index 8bfe23a..7d2ddbc 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -927,11 +927,12 @@ static int parse_symbol_and_return(int argc, const char *argv[], for (i = 2; i < argc; i++) { tmp = strstr(argv[i], "$retval"); if (tmp && !isalnum(tmp[7]) && tmp[7] != '_') { + if (is_tracepoint) { + trace_probe_log_set_index(i); + trace_probe_log_err(tmp - argv[i], RETVAL_ON_PROBE); + return -EINVAL; + } *is_return = true; - /* - * NOTE: Don't check is_tracepoint here, because it will - * be checked when the argument is parsed. - */ break; } } -- 2.7.4