diff options
| author | Amit Shah <amit.shah@redhat.com> | 2011-03-04 14:04:33 +1030 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-03-14 14:17:31 -0700 |
| commit | 310f5e480c6facfdf9ee9e6952e490eebd3d8d55 (patch) | |
| tree | fb03595d4a88f37d5a39f76b963ffc00fb7b0db6 | |
| parent | 381d256c50541d46b505b9da5c3e405fe603d886 (diff) | |
virtio: console: Don't access vqs if device was unplugged
commit d7a62cd0332115d4c7c4689abea0d889a30d8349 upstream.
If a virtio-console device gets unplugged while a port is open, a
subsequent close() call on the port accesses vqs to free up buffers.
This can lead to a crash.
The buffers are already freed up as a result of the call to
unplug_ports() from virtcons_remove(). The fix is to simply not access
vq information if port->portdev is NULL.
Reported-by: juzhang <juzhang@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | drivers/char/virtio_console.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index ad2520b1e03..e0d94739ffd 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -387,6 +387,10 @@ static void discard_port_data(struct port *port) unsigned int len; int ret; + if (!port->portdev) { + /* Device has been unplugged. vqs are already gone. */ + return; + } vq = port->in_vq; if (port->inbuf) buf = port->inbuf; @@ -469,6 +473,10 @@ static void reclaim_consumed_buffers(struct port *port) void *buf; unsigned int len; + if (!port->portdev) { + /* Device has been unplugged. vqs are already gone. */ + return; + } while ((buf = virtqueue_get_buf(port->out_vq, &len))) { kfree(buf); port->outvq_full = false; |