diff options
-rw-r--r-- | drivers/char/virtio_console.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index 2f2e31b58b34..c810481a5bc2 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c | |||
@@ -596,6 +596,10 @@ static ssize_t port_fops_write(struct file *filp, const char __user *ubuf, | |||
596 | ssize_t ret; | 596 | ssize_t ret; |
597 | bool nonblock; | 597 | bool nonblock; |
598 | 598 | ||
599 | /* Userspace could be out to fool us */ | ||
600 | if (!count) | ||
601 | return 0; | ||
602 | |||
599 | port = filp->private_data; | 603 | port = filp->private_data; |
600 | 604 | ||
601 | nonblock = filp->f_flags & O_NONBLOCK; | 605 | nonblock = filp->f_flags & O_NONBLOCK; |