diff options
author | Cathy Avery <cathy.avery@oracle.com> | 2015-10-02 09:35:01 -0400 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-11-09 12:50:25 -0800 |
commit | 294cf83fda51e9fc2f0c9dca79dda88110637e88 (patch) | |
tree | 123e18a85919124040ec59943be9a08b2d4439b0 | |
parent | d6a4980890d0d2dbdc326301d506799cce0dc824 (diff) |
xen-blkfront: check for null drvdata in blkback_changed (XenbusStateClosing)
commit a54c8f0f2d7df525ff997e2afe71866a1a013064 upstream.
xen-blkfront will crash if the check to talk_to_blkback()
in blkback_changed()(XenbusStateInitWait) returns an error.
The driver data is freed and info is set to NULL. Later during
the close process via talk_to_blkback's call to xenbus_dev_fatal()
the null pointer is passed to and dereference in blkfront_closing.
Signed-off-by: Cathy Avery <cathy.avery@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/block/xen-blkfront.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index e88556ac8318..d4285270f20c 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -1917,7 +1917,8 @@ static void blkback_changed(struct xenbus_device *dev, break; /* Missed the backend's Closing state -- fallthrough */ case XenbusStateClosing: - blkfront_closing(info); + if (info) + blkfront_closing(info); break; } } |