linux.git/drivers/block, branch v3.10.31

rbd: fix error handling from rbd_snap_name()

2014-01-09T20:24:26+00:00

commit da6a6b63978d45f9ae582d1f362f182012da3a22 upstream.

rbd_snap_name() calls rbd_dev_v{1,2}_snap_name() depending on the
format of the image. The format 1 version returns NULL on error, which
is handled by the caller. The format 2 version returns an ERR_PTR,
which the caller of rbd_snap_name() does not expect.

Fortunately this is unlikely to occur in practice because
rbd_snap_id_by_name() is called before rbd_snap_name(). This would hit
similar errors to rbd_snap_name() (like the snapshot not existing) and
return early, so rbd_snap_name() would not hit an error unless the
snapshot was removed between the two calls or memory was exhausted.

Use an ERR_PTR in rbd_dev_v1_snap_name() so that the specific error
can be propagated, and it is consistent with rbd_dev_v2_snap_name().
Handle the ERR_PTR in the only rbd_snap_name() caller.

Suggested-by: Alex Elder 
Signed-off-by: Josh Durgin 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

rbd: ignore unmapped snapshots that no longer exist

2014-01-09T20:24:26+00:00

commit efadc98aab674153709cc357ba565f04e3164fcd upstream.

This prevents erroring out while adding a device when a snapshot
unrelated to the current mapping is deleted between reading the
snapshot context and reading the snapshot names. If the mapped
snapshot name is not found an error still occurs as usual.

Signed-off-by: Josh Durgin 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

rbd: fix use-after free of rbd_dev->disk

2014-01-09T20:24:26+00:00

commit 9875201e10496612080e7d164acc8f625c18725c upstream.

Removing a device deallocates the disk, unschedules the watch, and
finally cleans up the rbd_dev structure. rbd_dev_refresh(), called
from the watch callback, updates the disk size and rbd_dev
structure. With no locking between them, rbd_dev_refresh() may use the
device or rbd_dev after they've been freed.

To fix this, check whether RBD_DEV_FLAG_REMOVING is set before
updating the disk size in rbd_dev_refresh(). In order to prevent a
race where rbd_dev_refresh() is already revalidating the disk when
rbd_remove() is called, move the call to rbd_bus_del_dev() after the
watch is unregistered and all notifies are complete. It's safe to
defer deleting this structure because no new requests can be submitted
once the RBD_DEV_FLAG_REMOVING is set, since the device cannot be
opened.

Fixes: http://tracker.ceph.com/issues/5636
Signed-off-by: Josh Durgin 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

rbd: make rbd_obj_notify_ack() synchronous

2014-01-09T20:24:26+00:00

commit 20e0af67ce88c657d0601977b9941a2256afbdaa upstream.

The only user of rbd_obj_notify_ack() is rbd_watch_cb(). It used
asynchronously with no tracking of when the notify ack completes, so
it may still be in progress when the osd_client is shut down.  This
results in a BUG() since the osd client assumes no requests are in
flight when it stops. Since all notifies are flushed before the
osd_client is stopped, waiting for the notify ack to complete before
returning from the watch callback ensures there are no notify acks in
flight during shutdown.

Rename rbd_obj_notify_ack() to rbd_obj_notify_ack_sync() to reflect
its new synchronous nature.

Signed-off-by: Josh Durgin 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

rbd: complete notifies before cleaning up osd_client and rbd_dev

2014-01-09T20:24:26+00:00

commit 9abc59908e0c5f983aaa91150da32d5b62cf60b7 upstream.

To ensure rbd_dev is not used after it's released, flush all pending
notify callbacks before calling rbd_dev_image_release(). No new
notifies can be added to the queue at this point because the watch has
already be unregistered with the osd_client.

Signed-off-by: Josh Durgin 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

rbd: fix null dereference in dout

2014-01-09T20:24:26+00:00

commit c35455791c1131e7ccbf56ea6fbdd562401c2ce2 upstream.

The order parameter is sometimes NULL in _rbd_dev_v2_snap_size(), but
the dout() always derefences it. Move this to another dout() protected
by a check that order is non-NULL.

Signed-off-by: Josh Durgin 
Reviewed-by: Sage Weil 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

rbd: fix buffer size for writes to images with snapshots

2014-01-09T20:24:25+00:00

commit 03507db631c94a48e316c7f638ffb2991544d617 upstream.

rbd_osd_req_create() needs to know the snapshot context size to create
a buffer large enough to send it with the message front. It gets this
from the img_request, which was not set for the obj_request yet. This
resulted in trying to write past the end of the front payload, hitting
this BUG:

libceph: BUG_ON(p > msg->front.iov_base + msg->front.iov_len);

Fix this by associating the obj_request with its img_request
immediately after it's created, before the osd request is created.

Fixes: http://tracker.ceph.com/issues/5760
Suggested-by: Alex Elder 
Signed-off-by: Josh Durgin 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

rbd: fix a couple warnings

2014-01-09T20:24:25+00:00

commit e976cad0f0dbe5440a4ca38e29e1f932d9319125 upstream.

gcc isn't quite smart enough and generates these warnings:

drivers/block/rbd.c: In function 'rbd_img_request_fill':
drivers/block/rbd.c:1266:22: warning: 'bio_list' may be used uninitialized in this function [-Wmaybe-uninitialized]
drivers/block/rbd.c:2186:14: note: 'bio_list' was declared here
drivers/block/rbd.c:2247:10: warning: 'pages' may be used uninitialized in this function [-Wmaybe-uninitialized]

even though they are initialized for their respective code paths.

Signed-off-by: Sage Weil 
Signed-off-by: Greg Kroah-Hartman

rbd: protect against concurrent unmaps

2014-01-09T20:24:25+00:00

commit 82a442d239695a242c4d584464c9606322cd02aa upstream.

Make sure two concurrent unmap operations on the same rbd device
won't collide, by only proceeding with the removal and cleanup of a
device if is not already underway.

Signed-off-by: Alex Elder 
Reviewed-by: Josh Durgin 
Signed-off-by: Greg Kroah-Hartman

rbd: set removing flag while holding list lock

2014-01-09T20:24:25+00:00

commit 751cc0e3cfabdda87c4c21519253c6751e97a8d4 upstream.

When unmapping a device, its id is supplied, and that is used to
look up which rbd device should be unmapped.  Looking up the
device involves searching the rbd device list while holding
a spinlock that protects access to that list.

Currently all of this is done under protection of the control lock,
but that protection is going away soon.  To ensure the rbd_dev is
still valid (still on the list) while setting its REMOVING flag, do
so while still holding the list lock.  To do so, get rid of
__rbd_get_dev(), and open code what it did in the one place it
was used.

Signed-off-by: Alex Elder 
Reviewed-by: Josh Durgin 
Signed-off-by: Greg Kroah-Hartman