3.6.11.9-rc1 stable review patch. If anyone has any objections, please let me know. ------------------ From: Amit Shah [ Upstream commit 671bdea2b9f210566610603ecbb6584c8a201c8c ] Between open() being called and processed, the port can be unplugged. Check if this happened, and bail out. A simple test script to reproduce this is: while true; do for i in $(seq 1 100); do echo $i > /dev/vport0p3; done; done; This opens and closes the port a lot of times; unplugging the port while this is happening triggers the bug. CC: Signed-off-by: Amit Shah Signed-off-by: Rusty Russell Signed-off-by: Steven Rostedt --- drivers/char/virtio_console.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index abca6eb..a57cc3b 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -798,6 +798,10 @@ static int port_fops_open(struct inode *inode, struct file *filp) /* We get the port with a kref here */ port = find_port_by_devt(cdev->dev); + if (!port) { + /* Port was unplugged before we could proceed */ + return -ENXIO; + } filp->private_data = port; /* -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/