[PATCH 3/4] xhci: debugfs: initialize command buffer

[Jiale Yao]

xhci_port_write() copies user input into an uninitialized stack buffer
and compares ten bytes against the compliance command. A short matching
prefix can make strncmp() inspect bytes that were not initialized.

Zero-initialize the buffer so the copied input is always terminated.

Fixes: 87a03802184c ("xhci: debugfs: add debugfs interface to enable compliance mode for a port")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Jiale Yao <yaojiale02@xxxxxxx>
---
 drivers/usb/host/xhci-debugfs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci-debugfs.c b/drivers/usb/host/xhci-debugfs.c
index 2aa01d99f23d..a020cbab9674 100644
--- a/drivers/usb/host/xhci-debugfs.c
+++ b/drivers/usb/host/xhci-debugfs.c
@@ -347,7 +347,7 @@ static ssize_t xhci_port_write(struct file *file,  const char __user *ubuf,
 	struct seq_file         *s = file->private_data;
 	struct xhci_port	*port = s->private;
 	struct xhci_hcd		*xhci = hcd_to_xhci(port->rhub->hcd);
-	char                    buf[32];
+	char                    buf[32] = { };
 	u32			portsc;
 	unsigned long		flags;
 
-- 
2.34.1