From 34423f250a372d71346922edf2b84a19d811a311 Mon Sep 17 00:00:00 2001
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Date: Wed, 22 Jan 2020 06:44:50 -0500
Subject: [PATCH] tracing: Fix uninitialized buffer var on early exit to
 trace_vbprintk()

If we exit due to a bad input to trace_printk() (highly unlikely), then the
buffer variable will not be initialized when we unnest the ring buffer.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 kernel/trace/trace.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 2e1db19dce97..d1410b4462ac 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3230,7 +3230,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
 	len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args);
 
 	if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0)
-		goto out;
+		goto out_put;
 
 	local_save_flags(flags);
 	size = sizeof(*entry) + sizeof(u32) * len;
@@ -3252,6 +3252,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
 
 out:
 	ring_buffer_nest_end(buffer);
+out_put:
 	put_trace_buf();
 
 out_nobuffer:
-- 
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