From e0a384434ae1bdfb03954c46c464e3dbd3223ad6 Mon Sep 17 00:00:00 2001 From: Martin Kaiser Date: Wed, 25 Mar 2026 00:47:01 +0900 Subject: [PATCH] tracing: fprobe: do not zero out unused fgraph_data If fprobe_entry does not fill the allocated fgraph_data completely, the unused part does not have to be zeroed. fgraph_data is a short-lived part of the shadow stack. The preceding length field allows locating the end regardless of the content. Link: https://lore.kernel.org/all/20260324084804.375764-1-martin@kaiser.cx/ Signed-off-by: Martin Kaiser Signed-off-by: Masami Hiramatsu (Google) --- kernel/trace/fprobe.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index dcadf1d23b8a..56d145017902 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -450,8 +450,6 @@ static int fprobe_fgraph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops used += FPROBE_HEADER_SIZE_IN_LONG + size_words; } } - if (used < reserved_words) - memset(fgraph_data + used, 0, reserved_words - used); /* If any exit_handler is set, data must be used. */ return used != 0;