[PATCH 4/4] usb: mtu3: initialize debugfs command buffer
From: Jiale Yao
Date: Wed Oct 21 2026 - 06:53:51 EST
ssusb_mode_write() copies user input into an uninitialized stack buffer
and compares fixed command lengths. A short write matching a command
prefix can make strncmp() inspect bytes that were not initialized.
Zero-initialize the buffer so the copied input is always terminated.
Fixes: 4aab6ad24a10 ("usb: mtu3: move vbus and mode debugfs interfaces into mtu3_debugfs.c")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Jiale Yao <yaojiale02@xxxxxxx>
---
drivers/usb/mtu3/mtu3_debugfs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/usb/mtu3/mtu3_debugfs.c b/drivers/usb/mtu3/mtu3_debugfs.c
index c003049bafbf..8976dbfaa585 100644
--- a/drivers/usb/mtu3/mtu3_debugfs.c
+++ b/drivers/usb/mtu3/mtu3_debugfs.c
@@ -423,7 +423,7 @@ static ssize_t ssusb_mode_write(struct file *file, const char __user *ubuf,
{
struct seq_file *sf = file->private_data;
struct ssusb_mtk *ssusb = sf->private;
- char buf[16];
+ char buf[16] = { };
if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
return -EFAULT;
--
2.34.1