linux/net/ceph, branch v3.6

libceph: only kunmap kmapped pages

2012-09-22T03:49:26Z

In write_partial_msg_pages(), pages need to be kmapped in order to perform a CRC-32c calculation on them. As an artifact of the way this code used to be structured, the kunmap() call was separated from the kmap() call and both were done conditionally. But the conditions under which the kmap() and kunmap() calls were made differed, so there was a chance a kunmap() call would be done on a page that had not been mapped. The symptom of this was tripping a BUG() in kunmap_high() when pkmap_count[nr] became 0. Reported-by: Bryan K. Wright Signed-off-by: Alex Elder Reviewed-by: Sage Weil

libceph: avoid truncation due to racing banners

2012-08-21T22:55:27Z

Because the Ceph client messenger uses a non-blocking connect, it is possible for the sending of the client banner to race with the arrival of the banner sent by the peer. When ceph_sock_state_change() notices the connect has completed, it schedules work to process the socket via con_work(). During this time the peer is writing its banner, and arrival of the peer banner races with con_work(). If con_work() calls try_read() before the peer banner arrives, there is nothing for it to do, after which con_work() calls try_write() to send the client's banner. In this case Ceph's protocol negotiation can complete succesfully. The server-side messenger immediately sends its banner and addresses after accepting a connect request, *before* actually attempting to read or verify the banner from the client. As a result, it is possible for the banner from the server to arrive before con_work() calls try_read(). If that happens, try_read() will read the banner and prepare protocol negotiation info via prepare_write_connect(). prepare_write_connect() calls con_out_kvec_reset(), which discards the as-yet-unsent client banner. Next, con_work() calls try_write(), which sends the protocol negotiation info rather than the banner that the peer is expecting. The result is that the peer sees an invalid banner, and the client reports "negotiation failed". Fix this by moving con_out_kvec_reset() out of prepare_write_connect() to its callers at all locations except the one where the banner might still need to be sent. [elder@inktak.com: added note about server-side behavior] Signed-off-by: Jim Schutt Reviewed-by: Alex Elder

libceph: delay debugfs initialization until we learn global_id

2012-08-20T17:03:15Z

The debugfs directory includes the cluster fsid and our unique global_id. We need to delay the initialization of the debug entry until we have learned both the fsid and our global_id from the monitor or else the second client can't create its debugfs entry and will fail (and multiple client instances aren't properly reflected in debugfs). Reported by: Yan, Zheng Signed-off-by: Sage Weil Reviewed-by: Yehuda Sadeh

libceph: fix crypto key null deref, memory leak

2012-08-02T16:19:20Z

Avoid crashing if the crypto key payload was NULL, as when it was not correctly allocated and initialized. Also, avoid leaking it. Signed-off-by: Sylvain Munaut Signed-off-by: Sage Weil Reviewed-by: Alex Elder

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client

2012-07-31T21:35:28Z

Pull Ceph changes from Sage Weil: "Lots of stuff this time around: - lots of cleanup and refactoring in the libceph messenger code, and many hard to hit races and bugs closed as a result. - lots of cleanup and refactoring in the rbd code from Alex Elder, mostly in preparation for the layering functionality that will be coming in 3.7. - some misc rbd cleanups from Josh Durgin that are finally going upstream - support for CRUSH tunables (used by newer clusters to improve the data placement) - some cleanup in our use of d_parent that Al brought up a while back - a random collection of fixes across the tree There is another patch coming that fixes up our ->atomic_open() behavior, but I'm going to hammer on it a bit more before sending it." Fix up conflicts due to commits that were already committed earlier in drivers/block/rbd.c, net/ceph/{messenger.c, osd_client.c} * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (132 commits) rbd: create rbd_refresh_helper() rbd: return obj version in __rbd_refresh_header() rbd: fixes in rbd_header_from_disk() rbd: always pass ops array to rbd_req_sync_op() rbd: pass null version pointer in add_snap() rbd: make rbd_create_rw_ops() return a pointer rbd: have __rbd_add_snap_dev() return a pointer libceph: recheck con state after allocating incoming message libceph: change ceph_con_in_msg_alloc convention to be less weird libceph: avoid dropping con mutex before fault libceph: verify state after retaking con lock after dispatch libceph: revoke mon_client messages on session restart libceph: fix handling of immediate socket connect failure ceph: update MAINTAINERS file libceph: be less chatty about stray replies libceph: clear all flags on con_close libceph: clean up con flags libceph: replace connection state bits with states libceph: drop unnecessary CLOSED check in socket state change callback libceph: close socket directly from ceph_con_close() ...

libceph: recheck con state after allocating incoming message

2012-07-31T01:19:45Z

We drop the lock when calling the ->alloc_msg() con op, which means we need to (a) not clobber con->in_msg without the mutex held, and (b) we need to verify that we are still in the OPEN state when we retake it to avoid causing any mayhem. If the state does change, -EAGAIN will get us back to con_work() and loop. Signed-off-by: Sage Weil Reviewed-by: Alex Elder

libceph: change ceph_con_in_msg_alloc convention to be less weird

2012-07-31T01:19:30Z

This function's calling convention is very limiting. In particular, we can't return any error other than ENOMEM (and only implicitly), which is a problem (see next patch). Instead, return an normal 0 or error code, and make the skip a pointer output parameter. Drop the useless in_hdr argument (we have the con pointer). Signed-off-by: Sage Weil Reviewed-by: Alex Elder

libceph: avoid dropping con mutex before fault

2012-07-31T01:17:13Z

The ceph_fault() function takes the con mutex, so we should avoid dropping it before calling it. This fixes a potential race with another thread calling ceph_con_close(), or _open(), or similar (we don't reverify con->state after retaking the lock). Add annotation so that lockdep realizes we will drop the mutex before returning. Signed-off-by: Sage Weil Reviewed-by: Alex Elder

libceph: verify state after retaking con lock after dispatch

2012-07-31T01:16:56Z

We drop the con mutex when delivering a message. When we retake the lock, we need to verify we are still in the OPEN state before preparing to read the next tag, or else we risk stepping on a connection that has been closed. Signed-off-by: Sage Weil Reviewed-by: Alex Elder

libceph: revoke mon_client messages on session restart

2012-07-31T01:16:40Z

Revoke all mon_client messages when we shut down the old connection. This is mostly moot since we are re-using the same ceph_connection, but it is cleaner. Signed-off-by: Sage Weil Reviewed-by: Alex Elder