diff options
| author | Cathy Avery <cathy.avery@oracle.com> | 2015-10-02 09:35:01 -0400 |
|---|---|---|
| committer | Jiri Slaby <jslaby@suse.cz> | 2015-11-12 14:09:01 +0100 |
| commit | 54001184d4c2f4660a783437d318d3868239690a (patch) | |
| tree | 861843fb2544894dec74942372a5f0dacdcb810b | |
| parent | 96c5ef590f6d974bb3cd03421b7824499c9e34e3 (diff) | |
| download | lwn-54001184d4c2f4660a783437d318d3868239690a.tar.gz lwn-54001184d4c2f4660a783437d318d3868239690a.zip | |
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: Jiri Slaby <jslaby@suse.cz>
| -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 7d0eb3f8d629..0b6932c376fb 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -1965,7 +1965,8 @@ 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; } } |