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path: root/fs/nfs/nfs4proc.c
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2011-07-20nfs_open_context doesn't need struct path eitherAl Viro
just dentry, please... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20nfs4_opendata doesn't need struct path eitherAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20nfs4_closedata doesn't need to mess with struct pathAl Viro
instead of path_get()/path_put(), we can just use nfs_sb_{,de}active() to pin the superblock down. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-06-15nfs4.1: fix several problems with _pnfs_return_layoutFred Isaman
_pnfs_return_layout had the following problems: - it did not call pnfs_free_lseg_list on all paths - it unintentionally did a forgetful return when there was no outstanding io - it raced with concurrent LAYOUTGETS Signed-off-by: Fred Isaman <iisaman@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-06-15NFSv4.1: allow nfs_fhget to succeed with mounted on fileidAndy Adamson
Commit 28331a46d88459788c8fca72dbb0415cd7f514c9 "Ensure we request the ordinary fileid when doing readdirplus" changed the meaning of NFS_ATTR_FATTR_FILEID which used to be set when FATTR4_WORD1_MOUNTED_ON_FILED was requested. Allow nfs_fhget to succeed with only a mounted on fileid when crossing a mountpoint or a referral. Ask for the fileid of the absent file system if mounted_on_fileid is not supported. Signed-off-by: Andy Adamson <andros@netapp.com> cc:stable@kernel.org [2.6.39] Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-06-15NFSv4.1: deprecate headerpadsz in CREATE_SESSIONBenny Halevy
We don't support header padding yet so better off ditching it Reported-by: Sid Moore <learnmost@gmail.com> Signed-off-by: Benny Halevy <benny@tonian.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-05-29Merge branch 'pnfs-submit' of git://git.open-osd.org/linux-open-osdLinus Torvalds
* 'pnfs-submit' of git://git.open-osd.org/linux-open-osd: (32 commits) pnfs-obj: pg_test check for max_io_size NFSv4.1: define nfs_generic_pg_test NFSv4.1: use pnfs_generic_pg_test directly by layout driver NFSv4.1: change pg_test return type to bool NFSv4.1: unify pnfs_pageio_init functions pnfs-obj: objlayout_encode_layoutcommit implementation pnfs: encode_layoutcommit pnfs-obj: report errors and .encode_layoutreturn Implementation. pnfs: encode_layoutreturn pnfs: layoutret_on_setattr pnfs: layoutreturn pnfs-obj: osd raid engine read/write implementation pnfs: support for non-rpc layout drivers pnfs-obj: define per-inode private structure pnfs: alloc and free layout_hdr layoutdriver methods pnfs-obj: objio_osd device information retrieval and caching pnfs-obj: decode layout, alloc/free lseg pnfs-obj: pnfs_osd XDR client implementation pnfs-obj: pnfs_osd XDR definitions pnfs-obj: objlayoutdriver module skeleton ...
2011-05-29pnfs: layoutret_on_setattrBenny Halevy
With the objects layout security model, we have object capabilities that are associated with the layout and we anticipate that the server will issue a cb_layoutrecall for any setattr that changes security related attributes (user/group/mode/acl) or truncates the file. Therefore, the layout is returned before issuing the setattr to avoid the anticipated cb_layoutrecall. Signed-off-by: Benny Halevy <bhalevy@panasas.com>
2011-05-29pnfs: layoutreturnBenny Halevy
NFSv4.1 LAYOUTRETURN implementation Currently, does not support layout-type payload encoding. Signed-off-by: Alexandros Batsakis <batsakis@netapp.com> Signed-off-by: Andy Adamson <andros@citi.umich.edu> Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com> Signed-off-by: Fred Isaman <iisaman@citi.umich.edu> Signed-off-by: Fred Isaman <iisaman@netapp.com> Signed-off-by: Marc Eshel <eshel@almaden.ibm.com> Signed-off-by: Zhang Jingwang <zhangjingwang@nrchpc.ac.cn> [call pnfs_return_layout right before pnfs_destroy_layout] [remove assert_spin_locked from pnfs_clear_lseg_list] [remove wait parameter from the layoutreturn path.] [remove return_type field from nfs4_layoutreturn_args] [remove range from nfs4_layoutreturn_args] [no need to send layoutcommit from _pnfs_return_layout] [don't wait on sync layoutreturn] [fix layout stateid in layoutreturn args] [fixed NULL deref in _pnfs_return_layout] [removed recaim member of nfs4_layoutreturn_args] Signed-off-by: Benny Halevy <bhalevy@panasas.com>
2011-05-29pnfs: support for non-rpc layout driversBenny Halevy
Non-rpc layout driver such as for objects and blocks implement their own I/O path and error handling logic. Therefore bypass NFS-based error handling for these layout drivers. [fix lseg ref-count bugs, and null de-refs] [Fall out from: non-rpc layout drivers] Signed-off-by: Boaz Harrosh <bharrosh@panasas.com> [get rid of PNFS_USE_RPC_CODE] [get rid of __nfs4_write_done_cb] [revert useless change in nfs4_write_done_cb] Signed-off-by: Benny Halevy <bhalevy@panasas.com>
2011-05-27NFSv4: Handle expired stateids when the lease is still validTrond Myklebust
Currently, if the server returns NFS4ERR_EXPIRED in reply to a READ or WRITE, but the RENEW test determines that the lease is still active, we fail to recover and end up looping forever in a READ/WRITE + RENEW death spiral. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: stable@kernel.org
2011-05-11NFSv41: Resend on NFS4ERR_RETRY_UNCACHED_REPAndy Adamson
Free the slot and resend the RPC with new session <slot#,seq#>. For nfs4_async_handle_error, return -EAGAIN and set the task->tk_status to 0 to restart the async rpc in the rpc_restart_call_prepare state which resets the slot. For nfs4_handle_exception, retrying a call that uses nfs4_call_sync will reset the slot via nfs41_call_sync_prepare. For open/close/lock/locku/delegreturn/layoutcommit/unlink/rename/write cachethis is true, so these operations will not trigger an NFS4ERR_RETRY_UNCACHED_REP. Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-24NFSv4: Ensure that clientid and session establishment can time outTrond Myklebust
The following patch ensures that we do not get permanently trapped in the RPC layer when trying to establish a new client id or session. This again ensures that the state manager can finish in a timely fashion when the last filesystem to reference the nfs_client exits. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-24NFSv4.1: Don't loop forever in nfs4_proc_create_sessionTrond Myklebust
If a server for some reason keeps sending NFS4ERR_DELAY errors, we can end up looping forever inside nfs4_proc_create_session, and so the usual mechanisms for detecting if the nfs_client is dead don't work. Fix this by ensuring that we loop inside the nfs4_state_manager thread instead. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-18NFSv4: Handle NFS4ERR_WRONGSEC outside of nfs4_handle_exception()Bryan Schumaker
I only want to try other secflavors during an initial mount if NFS4ERR_WRONGSEC is returned. nfs4_handle_exception() could potentially map other errors to EPERM, so we should handle this error specially for correctness. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-18NFSv4.1: Don't update sequence number if rpc_task is not sentBryan Schumaker
If we fail to contact the gss upcall program, then no message will be sent to the server. The client still updated the sequence number, however, and this lead to NFS4ERR_SEQ_MISMATCH for the next several RPC calls. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-13NFS: don't negotiate when user specifies sec flavorBryan Schumaker
We were always attempting sec flavor negotiation, even if the user told us a specific sec flavor to use. If that sec flavor fails, we should return an error rather than continuing with sec flavor negotiation. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-13NFS: Attempt mount with default sec flavor firstBryan Schumaker
nfs4_lookup_root() is already configured to use either RPC_AUTH_UNIX or a user specified flavor (through -o sec=<whatever>). We should use this flavor first, and only attempt negotiation if it fails with -EPERM. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-13NFS: flav_array honors NFS_MAX_SECFLAVORSBryan Schumaker
NFS_MAX_SECFLAVORS should already take into account RPC_AUTH_UNIX and RPC_AUTH_NULL, so we don't need to set aside extra slots for them. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-13NFS: Fix infinite loop in gss_create_upcall()Bryan Schumaker
There can be an infinite loop if gss_create_upcall() is called without the userspace program running. To prevent this, we return -EACCES if we notice that pipe_version hasn't changed (indicating that the pipe has not been opened). Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-07NFS: Change initial mount authflavor only when server returns NFS4ERR_WRONGSECBryan Schumaker
When attempting an initial mount, we should only attempt other authflavors if AUTH_UNIX receives a NFS4ERR_WRONGSEC error. This allows other errors to be passed back to userspace programs. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-24Merge branch 'nfs-for-2.6.39' into nfs-for-nextTrond Myklebust
2011-03-24Cleanup XDR parsing for LAYOUTGET, GETDEVICEINFOWeston Andros Adamson
changes LAYOUTGET and GETDEVICEINFO XDR parsing to: - not use vmap, which doesn't work on incoherent archs - use xdr_stream parsing for all xdr Signed-off-by: Weston Andros Adamson <dros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-24NFSv4.1 convert layoutcommit sync to booleanAndy Adamson
Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-24NFS: Determine initial mount securityBryan Schumaker
When sec=<something> is not presented as a mount option, we should attempt to determine what security flavor the server is using. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-24NFS: use secinfo when crossing mountpointsBryan Schumaker
A submount may use different security than the parent mount does. We should figure out what sec flavor the submount uses at mount time. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-24NFS: Add secinfo procedureBryan Schumaker
This patch adds the nfs4 operation secinfo as a valid nfs rpc operation. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-24NFS: lookup supports alternate clientBryan Schumaker
A later patch will need to perform a lookup using an alternate client with a different security flavor. This patch adds support for doing that on NFS v4. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-24NFS: convert call_sync() to a functionBryan Schumaker
This patch changes nfs4_call_sync() from a macro into a static inline function. As a macro, the call_sync() function will not do any type checking and depends on the sequence arguments always having the same name. As a function, we get to have type checking and can rename the arguments if we so choose. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-23NFSv4.1: layoutcommitAndy Adamson
The filelayout driver sends LAYOUTCOMMIT only when COMMIT goes to the data server (as opposed to the MDS) and the data server WRITE is not NFS_FILE_SYNC. Only whole file layout support means that there is only one IOMODE_RW layout segment. Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Alexandros Batsakis <batsakis@netapp.com> Signed-off-by: Boaz Harrosh <bharrosh@panasas.com> Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com> Signed-off-by: Fred Isaman <iisaman@citi.umich.edu> Signed-off-by: Mingyang Guo <guomingyang@nrchpc.ac.cn> Signed-off-by: Tao Guo <guotao@nrchpc.ac.cn> Signed-off-by: Zhang Jingwang <zhangjingwang@nrchpc.ac.cn> Tested-by: Boaz Harrosh <bharrosh@panasas.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: Fred Isaman <iisaman@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-23NFSv4.1: remove GETATTR from ds commitsFred Isaman
Any COMMIT compound directed to a data server needs to have the GETATTR calls suppressed. We here, make sure the field we are testing (data->lseg) is set and refcounted correctly. Signed-off-by: Fred Isaman <iisaman@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-23NFSv4.1: add callback to nfs4_commit_doneFred Isaman
Add a callback that the pnfs layout driver can use to do its own error handling of the data server's COMMIT response. Signed-off-by: Fred Isaman <iisaman@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11NFSv4: Send unmapped uid/gids to the server when using auth_sysTrond Myklebust
The new behaviour is enabled using the new module parameter 'nfs4_disable_idmapping'. Note that if the server rejects an unmapped uid or gid, then the client will automatically switch back to using the idmapper. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11NFSv4: Propagate the error NFS4ERR_BADOWNER to nfs4_do_setattrTrond Myklebust
This will be required in order to switch uid/gid mapping back on if the admin has tried to disable it. Note that we also propagate NFS4ERR_BADNAME at the same time, in order to work around a Linux server bug. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11NFSv4.1: pnfs filelayout driver writeFred Isaman
Allows the pnfs filelayout driver to write to the data servers. Note that COMMIT to data servers will be implemented in a future patch. To avoid improper behavior, for the moment any WRITE to a data server that would also require a COMMIT to the data server is sent NFS_FILE_SYNC. Signed-off-by: Andy Adamson <andros@citi.umich.edu> Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com> Signed-off-by: Fred Isaman <iisaman@citi.umich.edu> Signed-off-by: Mingyang Guo <guomingyang@nrchpc.ac.cn> Signed-off-by: Oleg Drokin <green@linuxhacker.ru> Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com> Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: Fred Isaman <iisaman@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11NFSv4.1: remove GETATTR from ds writesFred Isaman
Any WRITE compound directed to a data server needs to have the GETATTR calls suppressed. Signed-off-by: Fred Isaman <iisaman@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11NFSv4.1: add callback to nfs4_write_doneFred Isaman
Add callback that pnfs layout driver can use to do its own handling of data server WRITE response. Signed-off-by: Fred Isaman <iisaman@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11NFSv4.1: filelayout async error handlerAndy Adamson
Use our own async error handler. Mark the layout as failed and retry i/o through the MDS on specified errors. Update the mds_offset in nfs_readpage_retry so that a failed short-read retry to a DS gets correctly resent through the MDS. Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11NFSv4.1: filelayout readAndy Adamson
Attempt a pNFS file layout read by setting up the nfs_read_data struct and calling nfs_initiate_read with the data server rpc client and the filelayout rpc call ops. Error handling is implemented in a subsequent patch. Signed-off-by: Andy Adamson <andros@citi.umich.edu> Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com> Signed-off-by: Fred Isaman <iisaman@citi.umich.edu> Signed-off-by: Fred Isaman <iisaman@netapp.com> Signed-off-by: Mingyang Guo <guomingyang@nrchpc.ac.cn> Signed-off-by: Oleg Drokin <green@linuxhacker.ru> Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com> Tested-by: Guo Mingyang <guomingyang@nrchpc.ac.cn> Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11NFSv4.1: data server connectionAndy Adamson
Introduce a data server set_client and init session following the nfs4_set_client and nfs4_init_session convention. Once a new nfs_client is on the nfs_client_list, the nfs_client cl_cons_state serializes access to creating an nfs_client struct with matching properties. Use the new nfs_get_client() that initializes new clients. Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11NFS move nfs_client initialization into nfs_get_clientAndy Adamson
Now nfs_get_client returns an nfs_client ready to be used no matter if it was found or created. Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11nfs4: remove duplicated #includeHuang Weiyi
Remove duplicated #include('s) in fs/nfs/nfs4proc.c Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11NFSv4: Fix the setlk error handlerTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11NFSv4.1: Fix the handling of the SEQUENCE status bitsTrond Myklebust
We want SEQUENCE status bits to be handled by the state manager in order to avoid threading issues. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11NFSv4/4.1: Fix nfs4_schedule_state_recovery abusesTrond Myklebust
nfs4_schedule_state_recovery() should only be used when we need to force the state manager to check the lease. If we just want to start the state manager in order to handle a state recovery situation, we should be using nfs4_schedule_state_manager(). This patch fixes the abuses of nfs4_schedule_state_recovery() by replacing its use with a set of helper functions that do the right thing. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-10NFSv4.1 reclaim complete must wait for completionAndy Adamson
Signed-off-by: Andy Adamson <andros@netapp.com> [Trond: fix whitespace errors] Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-10NFSv4.1: Retry CREATE_SESSION on NFS4ERR_DELAYRicardo Labiaga
Fix bug where we currently retry the EXCHANGEID call again, eventhough we already have a valid clientid. Instead, delay and retry the CREATE_SESSION call. Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-10nfs: fix compilation warningJovi Zhang
this commit fix compilation warning as following: linux-2.6/fs/nfs/nfs4proc.c:3265: warning: comparison of distinct pointer types lacks a cast Signed-off-by: Jovi Zhang <bookjovi@gmail.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-10SUNRPC: Close a race in __rpc_wait_for_completion_task()Trond Myklebust
Although they run as rpciod background tasks, under normal operation (i.e. no SIGKILL), functions like nfs_sillyrename(), nfs4_proc_unlck() and nfs4_do_close() want to be fully synchronous. This means that when we exit, we want all references to the rpc_task to be gone, and we want any dentry references etc. held by that task to be released. For this reason these functions call __rpc_wait_for_completion_task(), followed by rpc_put_task() in the expectation that the latter will be releasing the last reference to the rpc_task, and thus ensuring that the callback_ops->rpc_release() has been called synchronously. This patch fixes a race which exists due to the fact that rpciod calls rpc_complete_task() (in order to wake up the callers of __rpc_wait_for_completion_task()) and then subsequently calls rpc_put_task() without ensuring that these two steps are done atomically. In order to avoid adding new spin locks, the patch uses the existing waitqueue spin lock to order the rpc_task reference count releases between the waiting process and rpciod. The common case where nobody is waiting for completion is optimised for by checking if the RPC_TASK_ASYNC flag is cleared and/or if the rpc_task reference count is 1: in those cases we drop trying to grab the spin lock, and immediately free up the rpc_task. Those few processes that need to put the rpc_task from inside an asynchronous context and that do not care about ordering are given a new helper: rpc_put_task_async(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-05nfs4: Ensure that ACL pages sent over NFS were not allocated from the slab (v3)Neil Horman
The "bad_page()" page allocator sanity check was reported recently (call chain as follows): bad_page+0x69/0x91 free_hot_cold_page+0x81/0x144 skb_release_data+0x5f/0x98 __kfree_skb+0x11/0x1a tcp_ack+0x6a3/0x1868 tcp_rcv_established+0x7a6/0x8b9 tcp_v4_do_rcv+0x2a/0x2fa tcp_v4_rcv+0x9a2/0x9f6 do_timer+0x2df/0x52c ip_local_deliver+0x19d/0x263 ip_rcv+0x539/0x57c netif_receive_skb+0x470/0x49f :virtio_net:virtnet_poll+0x46b/0x5c5 net_rx_action+0xac/0x1b3 __do_softirq+0x89/0x133 call_softirq+0x1c/0x28 do_softirq+0x2c/0x7d do_IRQ+0xec/0xf5 default_idle+0x0/0x50 ret_from_intr+0x0/0xa default_idle+0x29/0x50 cpu_idle+0x95/0xb8 start_kernel+0x220/0x225 _sinittext+0x22f/0x236 It occurs because an skb with a fraglist was freed from the tcp retransmit queue when it was acked, but a page on that fraglist had PG_Slab set (indicating it was allocated from the Slab allocator (which means the free path above can't safely free it via put_page. We tracked this back to an nfsv4 setacl operation, in which the nfs code attempted to fill convert the passed in buffer to an array of pages in __nfs4_proc_set_acl, which gets used by the skb->frags list in xs_sendpages. __nfs4_proc_set_acl just converts each page in the buffer to a page struct via virt_to_page, but the vfs allocates the buffer via kmalloc, meaning the PG_slab bit is set. We can't create a buffer with kmalloc and free it later in the tcp ack path with put_page, so we need to either: 1) ensure that when we create the list of pages, no page struct has PG_Slab set or 2) not use a page list to send this data Given that these buffers can be multiple pages and arbitrarily sized, I think (1) is the right way to go. I've written the below patch to allocate a page from the buddy allocator directly and copy the data over to it. This ensures that we have a put_page free-able page for every entry that winds up on an skb frag list, so it can be safely freed when the frame is acked. We do a put page on each entry after the rpc_call_sync call so as to drop our own reference count to the page, leaving only the ref count taken by tcp_sendpages. This way the data will be properly freed when the ack comes in Successfully tested by myself to solve the above oops. Note, as this is the result of a setacl operation that exceeded a page of data, I think this amounts to a local DOS triggerable by an uprivlidged user, so I'm CCing security on this as well. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> CC: Trond Myklebust <Trond.Myklebust@netapp.com> CC: security@kernel.org CC: Jeff Layton <jlayton@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>