[PATCH] tracing/probes: Ensure the uprobe buffer size is bigger than event size

[Masami Hiramatsu (Google)]

From: Masami Hiramatsu (Google) <mhira...@kernel.org>

Add BUILD_BUG_ON() to ensure the uprobe per-CPU working buffer
size is bigger than the event size.

Signed-off-by: Masami Hiramatsu (Google) <mhira...@kernel.org>
---
 kernel/trace/trace_uprobe.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 2cabf8a23ec5..c5ee7920dec6 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -979,6 +979,7 @@ static struct uprobe_cpu_buffer 
*prepare_uprobe_buffer(struct trace_uprobe *tu,
        ucb = uprobe_buffer_get();
        ucb->dsize = tu->tp.size + dsize;
 
+       BUILD_BUG_ON(MAX_UCB_BUFFER_SIZE < MAX_PROBE_EVENT_SIZE);
        if (WARN_ON_ONCE(ucb->dsize > MAX_UCB_BUFFER_SIZE)) {
                ucb->dsize = MAX_UCB_BUFFER_SIZE;
                dsize = MAX_UCB_BUFFER_SIZE - tu->tp.size;