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 14:37:37 -0800 |
commit | 55b31efcf3beca658566d35365329d3cbb44044f (patch) | |
tree | 6a98e16ac67888fc953ad8ff27cd376e9ae0e467 | |
parent | 9addc07f2c7a7e0ccb9f25d4aae36497c35c1068 (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 7a8a73f1fc04..d68b08ae4be1 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -1984,7 +1984,8 @@ 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; } } |