kernel/linux.git/net/ceph/messenger.c, branch linux-4.20.y

libceph: handle an empty authorize reply

2019-02-27T09:09:41+00:00

commit 0fd3fd0a9bb0b02b6435bb7070e9f7b82a23f068 upstream. The authorize reply can be empty, for example when the ticket used to build the authorizer is too old and TAG_BADAUTHORIZER is returned from the service. Calling ->verify_authorizer_reply() results in an attempt to decrypt and validate (somewhat) random data in au->buf (most likely the signature block from calc_signature()), which fails and ends up in con_fault_finish() with !con->auth_retry. The ticket isn't invalidated and the connection is retried again and again until a new ticket is obtained from the monitor: libceph: osd2 192.168.122.1:6809 bad authorize reply libceph: osd2 192.168.122.1:6809 bad authorize reply libceph: osd2 192.168.122.1:6809 bad authorize reply libceph: osd2 192.168.122.1:6809 bad authorize reply Let TAG_BADAUTHORIZER handler kick in and increment con->auth_retry. Cc: stable@vger.kernel.org Fixes: 5c056fdc5b47 ("libceph: verify authorize reply on connect") Link: https://tracker.ceph.com/issues/20164 Signed-off-by: Ilya Dryomov Reviewed-by: Sage Weil Signed-off-by: Greg Kroah-Hartman

libceph: avoid KEEPALIVE_PENDING races in ceph_con_keepalive()

2019-02-15T07:11:07+00:00

commit 4aac9228d16458cedcfd90c7fb37211cf3653ac3 upstream. con_fault() can transition the connection into STANDBY right after ceph_con_keepalive() clears STANDBY in clear_standby(): libceph user thread ceph-msgr worker ceph_con_keepalive() mutex_lock(&con->mutex) clear_standby(con) mutex_unlock(&con->mutex) mutex_lock(&con->mutex) con_fault() ... if KEEPALIVE_PENDING isn't set set state to STANDBY ... mutex_unlock(&con->mutex) set KEEPALIVE_PENDING set WRITE_PENDING This triggers warnings in clear_standby() when either ceph_con_send() or ceph_con_keepalive() get to clearing STANDBY next time. I don't see a reason to condition queue_con() call on the previous value of KEEPALIVE_PENDING, so move the setting of KEEPALIVE_PENDING into the critical section -- unlike WRITE_PENDING, KEEPALIVE_PENDING could have been a non-atomic flag. Reported-by: syzbot+acdeb633f6211ccdf886@syzkaller.appspotmail.com Signed-off-by: Ilya Dryomov Tested-by: Myungho Jung Signed-off-by: Greg Kroah-Hartman

libceph: fall back to sendmsg for slab pages

2018-11-19T16:59:47+00:00

skb_can_coalesce() allows coalescing neighboring slab objects into a single frag: return page == skb_frag_page(frag) && off == frag->page_offset + skb_frag_size(frag); ceph_tcp_sendpage() can be handed slab pages. One example of this is XFS: it passes down sector sized slab objects for its metadata I/O. If the kernel client is co-located on the OSD node, the skb may go through loopback and pop on the receive side with the exact same set of frags. When tcp_recvmsg() attempts to copy out such a frag, hardened usercopy complains because the size exceeds the object's allocated size: usercopy: kernel memory exposure attempt detected from ffff9ba917f20a00 (kmalloc-512) (1024 bytes) Although skb_can_coalesce() could be taught to return false if the resulting frag would cross a slab object boundary, we already have a fallback for non-refcounted pages. Utilize it for slab pages too. Cc: stable@vger.kernel.org # 4.8+ Signed-off-by: Ilya Dryomov

Merge branch 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2018-11-02T02:58:52+00:00

Pull AFS updates from Al Viro: "AFS series, with some iov_iter bits included" * 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits) missing bits of "iov_iter: Separate type from direction and use accessor functions" afs: Probe multiple fileservers simultaneously afs: Fix callback handling afs: Eliminate the address pointer from the address list cursor afs: Allow dumping of server cursor on operation failure afs: Implement YFS support in the fs client afs: Expand data structure fields to support YFS afs: Get the target vnode in afs_rmdir() and get a callback on it afs: Calc callback expiry in op reply delivery afs: Fix FS.FetchStatus delivery from updating wrong vnode afs: Implement the YFS cache manager service afs: Remove callback details from afs_callback_break struct afs: Commit the status on a new file/dir/symlink afs: Increase to 64-bit volume ID and 96-bit vnode ID for YFS afs: Don't invoke the server to read data beyond EOF afs: Add a couple of tracepoints to log I/O errors afs: Handle EIO from delivery function afs: Fix TTL on VL server and address lists afs: Implement VL server rotation afs: Improve FS server rotation error handling ...

iov_iter: Separate type from direction and use accessor functions

2018-10-23T23:41:07+00:00

In the iov_iter struct, separate the iterator type from the iterator direction and use accessor functions to access them in most places. Convert a bunch of places to use switch-statements to access them rather then chains of bitwise-AND statements. This makes it easier to add further iterator types. Also, this can be more efficient as to implement a switch of small contiguous integers, the compiler can use ~50% fewer compare instructions than it has to use bitwise-and instructions. Further, cease passing the iterator type into the iterator setup function. The iterator function can set that itself. Only the direction is required. Signed-off-by: David Howells

libceph: preallocate message data items

2018-10-22T08:28:22+00:00

Currently message data items are allocated with ceph_msg_data_create() in setup_request_data() inside send_request(). send_request() has never been allowed to fail, so each allocation is followed by a BUG_ON: data = ceph_msg_data_create(...); BUG_ON(!data); It's been this way since support for multiple message data items was added in commit 6644ed7b7e04 ("libceph: make message data be a pointer") in 3.10. There is no reason to delay the allocation of message data items until the last possible moment and we certainly don't need a linked list of them as they are only ever appended to the end and never erased. Make ceph_msg_new2() take max_data_items and adapt the rest of the code. Reported-by: Jerry Lee Signed-off-by: Ilya Dryomov

libceph: don't consume a ref on pagelist in ceph_msg_data_add_pagelist()

2018-10-22T08:28:21+00:00

Because send_mds_reconnect() wants to send a message with a pagelist and pass the ownership to the messenger, ceph_msg_data_add_pagelist() consumes a ref which is then put in ceph_msg_data_destroy(). This makes managing pagelists in the OSD client (where they are wrapped in ceph_osd_data) unnecessarily hard because the handoff only happens in ceph_osdc_start_request() instead of when the pagelist is passed to ceph_osd_data_pagelist_init(). I counted several memory leaks on various error paths. Fix up ceph_msg_data_add_pagelist() and carry a pagelist ref in ceph_osd_data. Signed-off-by: Ilya Dryomov

libceph: check authorizer reply/challenge length before reading

2018-08-02T19:33:26+00:00

Avoid scribbling over memory if the received reply/challenge is larger than the buffer supplied with the authorizer. Signed-off-by: Ilya Dryomov Reviewed-by: Sage Weil

libceph: add authorizer challenge

2018-08-02T19:33:24+00:00

When a client authenticates with a service, an authorizer is sent with a nonce to the service (ceph_x_authorize_[ab]) and the service responds with a mutation of that nonce (ceph_x_authorize_reply). This lets the client verify the service is who it says it is but it doesn't protect against a replay: someone can trivially capture the exchange and reuse the same authorizer to authenticate themselves. Allow the service to reject an initial authorizer with a random challenge (ceph_x_authorize_challenge). The client then has to respond with an updated authorizer proving they are able to decrypt the service's challenge and that the new authorizer was produced for this specific connection instance. The accepting side requires this challenge and response unconditionally if the client side advertises they have CEPHX_V2 feature bit. This addresses CVE-2018-1128. Link: http://tracker.ceph.com/issues/24836 Signed-off-by: Ilya Dryomov Reviewed-by: Sage Weil

libceph: factor out __prepare_write_connect()

2018-08-02T19:33:22+00:00

Will be used for sending ceph_msg_connect with an updated authorizer, after the server challenges the initial authorizer. Signed-off-by: Ilya Dryomov Reviewed-by: Sage Weil