Subject: virtio: console: Disable lseek(2) for port file operations Date: Thu, 16 Sep 2010 14:43:09 +0530 From: Amit Shah The ports are char devices; do not have seeking capabilities. Calling nonseekable_open() from the fops_open() call and setting the llseek fops pointer to no_llseek ensures an lseek() call from userspace returns -ESPIPE. Signed-off-by: Amit Shah CC: Arnd Bergmann Signed-off-by: Rusty Russell --- drivers/char/virtio_console.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index 2dbcd41..28718a9 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -798,6 +798,8 @@ static int port_fops_open(struct inode *inode, struct file *filp) reclaim_consumed_buffers(port); spin_unlock_irq(&port->outvq_lock); + nonseekable_open(inode, filp); + /* Notify host of port being opened */ send_control_msg(filp->private_data, VIRTIO_CONSOLE_PORT_OPEN, 1); @@ -829,6 +831,7 @@ static const struct file_operations port_fops = { .poll = port_fops_poll, .release = port_fops_release, .fasync = port_fops_fasync, + .llseek = no_llseek, }; /*