[PATCH 5.11 267/775] ASoC: SOF: debug: Fix a potential issue on string buffer termination

[Greg Kroah-Hartman]

From: Hui Wang <hui.wang@xxxxxxxxxxxxx>

[ Upstream commit 9037c3bde65d339017ef41d81cb58069ffc321d4 ]

The function simple_write_to_buffer() doesn't add string termination
at the end of buf, we need to handle it on our own. This change refers
to the function tokenize_input() in debug.c and the function
sof_dfsentry_trace_filter_write() in trace.c.

Fixes: 091c12e1f50c ("ASoC: SOF: debug: add new debugfs entries for IPC flood test")
Reviewed-by: Kai Vehmanen <kai.vehmanen@xxxxxxxxxxxxxxx>
Signed-off-by: Hui Wang <hui.wang@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20210208103857.75705-1-hui.wang@xxxxxxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 sound/soc/sof/debug.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/sof/debug.c b/sound/soc/sof/debug.c
index 30213a1beaaa2..715a374b33cfb 100644
--- a/sound/soc/sof/debug.c
+++ b/sound/soc/sof/debug.c
@@ -352,7 +352,7 @@ static ssize_t sof_dfsentry_write(struct file *file, const char __user *buffer,
 	char *string;
 	int ret;
 
-	string = kzalloc(count, GFP_KERNEL);
+	string = kzalloc(count+1, GFP_KERNEL);
 	if (!string)
 		return -ENOMEM;
 
-- 
2.27.0