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2013-04-30Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem update from James Morris: "Just some minor updates across the subsystem" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: ima: eliminate passing d_name.name to process_measurement() TPM: Retry SaveState command in suspend path tpm/tpm_i2c_infineon: Add small comment about return value of __i2c_transfer tpm/tpm_i2c_infineon.c: Add OF attributes type and name to the of_device_id table entries tpm_i2c_stm_st33: Remove duplicate inclusion of header files tpm: Add support for new Infineon I2C TPM (SLB 9645 TT 1.2 I2C) char/tpm: Convert struct i2c_msg initialization to C99 format drivers/char/tpm/tpm_ppi: use strlcpy instead of strncpy tpm/tpm_i2c_stm_st33: formatting and white space changes Smack: include magic.h in smackfs.c selinux: make security_sb_clone_mnt_opts return an error on context mismatch seccomp: allow BPF_XOR based ALU instructions. Fix NULL pointer dereference in smack_inode_unlink() and smack_inode_rmdir() Smack: add support for modification of existing rules smack: SMACK_MAGIC to include/uapi/linux/magic.h Smack: add missing support for transmute bit in smack_str_from_perm() Smack: prevent revoke-subject from failing when unseen label is written to it tomoyo: use DEFINE_SRCU() to define tomoyo_ss tomoyo: use DEFINE_SRCU() to define tomoyo_ss
2013-04-30Merge tag 'nfs-for-3.10-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds
Pull NFS client bugfixes and cleanups from Trond Myklebust: - NLM: stable fix for NFSv2/v3 blocking locks - NFSv4.x: stable fixes for the delegation recall error handling code - NFSv4.x: Security flavour negotiation fixes and cleanups by Chuck Lever - SUNRPC: A number of RPCSEC_GSS fixes and cleanups also from Chuck - NFSv4.x assorted state management and reboot recovery bugfixes - NFSv4.1: In cases where we have already looked up a file, and hold a valid filehandle, use the new open-by-filehandle operation instead of opening by name. - Allow the NFSv4.1 callback thread to freeze - NFSv4.x: ensure that file unlock waits for readahead to complete - NFSv4.1: ensure that the RPC layer doesn't override the NFS session table size negotiation by limiting the number of slots. - NFSv4.x: Fix SETATTR spec compatibility issues * tag 'nfs-for-3.10-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (67 commits) NFSv4: Warn once about servers that incorrectly apply open mode to setattr NFSv4: Servers should only check SETATTR stateid open mode on size change NFSv4: Don't recheck permissions on open in case of recovery cached open NFSv4.1: Don't do a delegated open for NFS4_OPEN_CLAIM_DELEG_CUR_FH modes NFSv4.1: Use the more efficient open_noattr call for open-by-filehandle NFS: Retry SETCLIENTID with AUTH_SYS instead of AUTH_NONE NFSv4: Ensure that we clear the NFS_OPEN_STATE flag when appropriate LOCKD: Ensure that nlmclnt_block resets block->b_status after a server reboot NFSv4: Ensure the LOCK call cannot use the delegation stateid NFSv4: Use the open stateid if the delegation has the wrong mode nfs: Send atime and mtime as a 64bit value NFSv4: Record the OPEN create mode used in the nfs4_opendata structure NFSv4.1: Set the RPC_CLNT_CREATE_INFINITE_SLOTS flag for NFSv4.1 transports SUNRPC: Allow rpc_create() to request that TCP slots be unlimited SUNRPC: Fix a livelock problem in the xprt->backlog queue NFSv4: Fix handling of revoked delegations by setattr NFSv4 release the sequence id in the return on close case nfs: remove unnecessary check for NULL inode->i_flock from nfs_delegation_claim_locks NFS: Ensure that NFS file unlock waits for readahead to complete NFS: Add functionality to allow waiting on all outstanding reads to complete ...
2013-04-30Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina: "Usual stuff, mostly comment fixes, typo fixes, printk fixes and small code cleanups" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (45 commits) mm: Convert print_symbol to %pSR gfs2: Convert print_symbol to %pSR m32r: Convert print_symbol to %pSR iostats.txt: add easy-to-find description for field 6 x86 cmpxchg.h: fix wrong comment treewide: Fix typo in printk and comments doc: devicetree: Fix various typos docbook: fix 8250 naming in device-drivers pata_pdc2027x: Fix compiler warning treewide: Fix typo in printks mei: Fix comments in drivers/misc/mei treewide: Fix typos in kernel messages pm44xx: Fix comment for "CONFIG_CPU_IDLE" doc: Fix typo "CONFIG_CGROUP_CGROUP_MEMCG_SWAP" mmzone: correct "pags" to "pages" in comment. kernel-parameters: remove outdated 'noresidual' parameter Remove spurious _H suffixes from ifdef comments sound: Remove stray pluses from Kconfig file radio-shark: Fix printk "CONFIG_LED_CLASS" doc: put proper reference to CONFIG_MODULE_SIG_ENFORCE ...
2013-04-29NFSv4: Warn once about servers that incorrectly apply open mode to setattrTrond Myklebust
Debugging aid to help identify servers that incorrectly apply open mode checks to setattr requests that are not changing the file size. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-29NFSv4: Servers should only check SETATTR stateid open mode on size changeTrond Myklebust
The NFSv4 and NFSv4.1 specs are both clear that the server should only check stateid open mode if a SETATTR specifies the size attribute. If the open mode is not one that allows writing, then it returns NFS4ERR_OPENMODE. In the case where the SETATTR is not changing the size, the client will still pass it the delegation stateid to ensure that the server does not recall that delegation. In that case, the server should _ignore_ the delegation open mode, and simply apply standard permission checks. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-23Merge branch 'bugfixes' into linux-nextTrond Myklebust
Fix up a conflict between the linux-next branch and mainline. Conflicts: fs/nfs/nfs4proc.c
2013-04-23Merge branch 'rpcsec_gss-from_cel' into linux-nextTrond Myklebust
* rpcsec_gss-from_cel: (21 commits) NFS: Retry SETCLIENTID with AUTH_SYS instead of AUTH_NONE NFSv4: Don't clear the machine cred when client establish returns EACCES NFSv4: Fix issues in nfs4_discover_server_trunking NFSv4: Fix the fallback to AUTH_NULL if krb5i is not available NFS: Use server-recommended security flavor by default (NFSv3) SUNRPC: Don't recognize RPC_AUTH_MAXFLAVOR NFS: Use "krb5i" to establish NFSv4 state whenever possible NFS: Try AUTH_UNIX when PUTROOTFH gets NFS4ERR_WRONGSEC NFS: Use static list of security flavors during root FH lookup recovery NFS: Avoid PUTROOTFH when managing leases NFS: Clean up nfs4_proc_get_rootfh NFS: Handle missing rpc.gssd when looking up root FH SUNRPC: Remove EXPORT_SYMBOL_GPL() from GSS mech switch SUNRPC: Make gss_mech_get() static SUNRPC: Refactor nfsd4_do_encode_secinfo() SUNRPC: Consider qop when looking up pseudoflavors SUNRPC: Load GSS kernel module by OID SUNRPC: Introduce rpcauth_get_pseudoflavor() SUNRPC: Define rpcsec_gss_info structure NFS: Remove unneeded forward declaration ...
2013-04-23NFSv4: Don't recheck permissions on open in case of recovery cached openTrond Myklebust
If we already checked the user access permissions on the original open, then don't bother checking again on recovery. Doing so can cause a deadlock with NFSv4.1, since the may_open() operation is not privileged. Furthermore, we can't report an access permission failure here anyway. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-23NFSv4.1: Don't do a delegated open for NFS4_OPEN_CLAIM_DELEG_CUR_FH modesTrond Myklebust
If we're in a delegation recall situation, we can't do a delegated open. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-23NFSv4.1: Use the more efficient open_noattr call for open-by-filehandleTrond Myklebust
When we're doing open-by-filehandle in NFSv4.1, we shouldn't need to do the cache consistency revalidation on the directory. It is therefore more efficient to just use open_noattr, which returns the file attributes, but not the directory attributes. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-22NFS: Retry SETCLIENTID with AUTH_SYS instead of AUTH_NONEChuck Lever
Recently I changed the SETCLIENTID code to use AUTH_GSS(krb5i), and then retry with AUTH_NONE if that didn't work. This was to enable Kerberos NFS mounts to work without forcing Linux NFS clients to have a keytab on hand. Rick Macklem reports that the FreeBSD server accepts AUTH_NONE only for NULL operations (thus certainly not for SETCLIENTID). Falling back to AUTH_NONE means our proposed 3.10 NFS client will not interoperate with FreeBSD servers over NFSv4 unless Kerberos is fully configured on both ends. If the Linux client falls back to using AUTH_SYS instead for SETCLIENTID, all should work fine as long as the NFS server is configured to allow AUTH_SYS for SETCLIENTID. This may still prevent access to Kerberos-only FreeBSD servers by Linux clients with no keytab. Rick is of the opinion that the security settings the server applies to its pseudo-fs should also apply to the SETCLIENTID operation. Linux and Solaris NFS servers do not place that limitation on SETCLIENTID. The security settings for the server's pseudo-fs are determined automatically as the union of security flavors allowed on real exports, as recommended by RFC 3530bis; and the flavors allowed for SETCLIENTID are all flavors supported by the respective server implementation. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-22NFSv4: Ensure that we clear the NFS_OPEN_STATE flag when appropriateTrond Myklebust
We should always clear it before initiating file recovery. Also ensure that we clear it after a CLOSE and/or after TEST_STATEID fails. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-20NFSv4: Ensure the LOCK call cannot use the delegation stateidTrond Myklebust
Defensive patch to ensure that we copy the state->open_stateid, which can never be set to the delegation stateid. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-20NFSv4: Use the open stateid if the delegation has the wrong modeTrond Myklebust
Fix nfs4_select_rw_stateid() so that it chooses the open stateid (or an all-zero stateid) if the delegation does not match the selected read/write mode. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-19nfs: Send atime and mtime as a 64bit valueBryan Schumaker
RFC 3530 says that the seconds value of a nfstime4 structure is a 64bit value, but we are instead sending a 32-bit 0 and then a 32bit conversion of the 64bit Linux value. This means that if we try to set atime to a value before the epoch (touch -t 196001010101) the client will only send part of the new value due to lost precision. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-16NFSv4: Record the OPEN create mode used in the nfs4_opendata structureTrond Myklebust
If we're doing NFSv4.1 against a server that has persistent sessions, then we should not need to call SETATTR in order to reset the file attributes immediately after doing an exclusive create. Note that since the create mode depends on the type of session that has been negotiated with the server, we should not choose the mode until after we've got a session slot. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-14NFSv4.1: Set the RPC_CLNT_CREATE_INFINITE_SLOTS flag for NFSv4.1 transportsTrond Myklebust
This ensures that the RPC layer doesn't override the NFS session negotiation. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-12NFSv4: Fix handling of revoked delegations by setattrTrond Myklebust
Currently, _nfs4_do_setattr() will use the delegation stateid if no writeable open file stateid is available. If the server revokes that delegation stateid, then the call to nfs4_handle_exception() will fail to handle the error due to the lack of a struct nfs4_state, and will just convert the error into an EIO. This patch just removes the requirement that we must have a struct nfs4_state in order to invalidate the delegation and retry. Reported-by: Andy Adamson <andros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-12treewide: Fix typo in printksMasanari Iida
Correct spelling typos in printk and comments. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-04-11NFSv4 release the sequence id in the return on close caseAndy Adamson
Otherwise we deadlock if state recovery is initiated while we sleep. Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-10nfs: remove unnecessary check for NULL inode->i_flock from ↵Jeff Layton
nfs_delegation_claim_locks The second check was added in commit 65b62a29 but it will never be true. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-10Merge tag 'nfs-for-3.9-5' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds
Pull another nfs fixlet from Trond Myklebust: "I suddenly noticed that a one-line issue that I _thought_ I had fixed with the nfs41_walk_client_list patch was apparently still there in the pull request I sent earlier today. I'm very sorry for not catching that in time. - Fix a brain fart in nfs41_walk_client_list" * tag 'nfs-for-3.9-5' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: NFSv4: Doh! Typo in the fix to nfs41_walk_client_list
2013-04-10NFSv4: Doh! Typo in the fix to nfs41_walk_client_listTrond Myklebust
Make sure that we set the status to 0 on success. Missed in testing because it never appears when doing multiple mounts to _different_ servers. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: <stable@vger.kernel.org> # 3.7.x: 7b1f1fd: NFSv4/4.1: Fix bugs in nfs4[01]_walk_client_list
2013-04-10Merge tag 'nfs-for-3.9-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds
Pull NFS client bugfixes from Trond Myklebust: - fix for memory corruption issues in nfs4[01]_walk_client_list (stable) - fix for an Oopsable bug in rpc_clone_client (stable) - another state manager deadlock in the NFSv4 open code - memory leaks in nfs4_discover_server_trunking and rpc_new_client * tag 'nfs-for-3.9-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: NFSv4: Fix another potential state manager deadlock SUNRPC: Fix a potential memory leak in rpc_new_client NFSv4/4.1: Fix bugs in nfs4[01]_walk_client_list NFSv4: Fix a memory leak in nfs4_discover_server_trunking SUNRPC: Remove extra xprt_put()
2013-04-09NFSv4: Fix another potential state manager deadlockTrond Myklebust
Don't hold the NFSv4 sequence id while we check for open permission. The call to ACCESS may block due to reboot recovery. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-08NFS: Ensure that NFS file unlock waits for readahead to completeTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-08NFS: Add functionality to allow waiting on all outstanding reads to completeTrond Myklebust
This will later allow NFS locking code to wait for readahead to complete before releasing byte range locks. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-08NFSv4: Handle timeouts correctly when probing for lease validityTrond Myklebust
When we send a RENEW or SEQUENCE operation in order to probe if the lease is still valid, we want it to be able to time out since the lease we are probing is likely to time out too. Currently, because we use soft mount semantics for these RPC calls, the return value is EIO, which causes the state manager to exit with an "unhandled error" message. This patch changes the call semantics, so that the RPC layer returns ETIMEDOUT instead of EIO. We then have the state manager default to a simple retry instead of exiting. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-05NFSv4: Fix CB_RECALL_ANY to only return delegations that are not in useTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-05NFSv4: Clean up nfs_expire_all_delegationsTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-05NFSv4: Fix nfs_server_return_all_delegationsTrond Myklebust
If the state manager thread is already running, we may end up racing with it in nfs_client_return_marked_delegations. Better to just allow the state manager thread to do the job. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-05NFSv4: Be less aggressive about returning delegations for open filesTrond Myklebust
Currently, if the application that holds the file open isn't doing I/O, we may end up returning the delegation. This means that we can no longer cache the file as aggressively, and often also that we multiply the state that both the server and the client needs to track. This patch adds a check for open files to the routine that scans for delegations that are unreferenced. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-05NFSv4: Clean up delegation recall error handlingTrond Myklebust
Unify the error handling in nfs4_open_delegation_recall and nfs4_lock_delegation_recall. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-05NFSv4: Clean up nfs4_open_delegation_recallTrond Myklebust
Make it symmetric with nfs4_lock_delegation_recall Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-05NFSv4: Clean up nfs4_lock_delegation_recallTrond Myklebust
All error cases are handled by the switch() statement, meaning that the call to nfs4_handle_exception() is unreachable. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-05NFSv4: Handle NFS4ERR_DELAY and NFS4ERR_GRACE in nfs4_open_delegation_recallTrond Myklebust
A server shouldn't normally return NFS4ERR_GRACE if the client holds a delegation, since no conflicting lock reclaims can be granted, however the spec does not require the server to grant the open in this instance Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: stable@vger.kernel.org
2013-04-05NFSv4: Handle NFS4ERR_DELAY and NFS4ERR_GRACE in nfs4_lock_delegation_recallTrond Myklebust
A server shouldn't normally return NFS4ERR_GRACE if the client holds a delegation, since no conflicting lock reclaims can be granted, however the spec does not require the server to grant the lock in this instance. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: stable@vger.kernel.org
2013-04-05nfs: allow the v4.1 callback thread to freezeJeff Layton
The v4.1 callback thread has set_freezable() at the top, but it doesn't ever try to freeze within the loop. Have it call try_to_freeze() at the top of the loop. If a freeze event occurs, recheck kthread_should_stop() after thawing. Reported-by: Yanchuan Nian <ycnian@gmail.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-05NFSv4/4.1: Fix bugs in nfs4[01]_walk_client_listTrond Myklebust
It is unsafe to use list_for_each_entry_safe() here, because when we drop the nn->nfs_client_lock, we pin the _current_ list entry and ensure that it stays in the list, but we don't do the same for the _next_ list entry. Use of list_for_each_entry() is therefore the correct thing to do. Also fix the refcounting in nfs41_walk_client_list(). Finally, ensure that the nfs_client has finished being initialised and, in the case of NFSv4.1, that the session is set up. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Bryan Schumaker <bjschuma@netapp.com> Cc: stable@vger.kernel.org [>= 3.7]
2013-04-05NFSv4: Fix a memory leak in nfs4_discover_server_trunkingTrond Myklebust
When we assign a new rpc_client to clp->cl_rpcclient, we need to destroy the old one. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: stable@vger.kernel.org [>=3.7]
2013-04-05NFSv4: Don't clear the machine cred when client establish returns EACCESTrond Myklebust
The expected behaviour is that the client will decide at mount time whether or not to use a krb5i machine cred, or AUTH_NULL. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Bryan Schumaker <bjschuma@netapp.com>
2013-04-05NFSv4: Fix issues in nfs4_discover_server_trunkingTrond Myklebust
- Ensure that we exit with ENOENT if the call to ops->get_clid_cred() fails. - Handle the case where ops->detect_trunking() exits with an unexpected error, and return EIO. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-04NFSv4: Fix the fallback to AUTH_NULL if krb5i is not availableTrond Myklebust
If the rpcsec_gss_krb5 module cannot be loaded, the attempt to create an rpc_client in nfs4_init_client will currently fail with an EINVAL. Fix is to retry with AUTH_NULL. Regression introduced by the commit "NFS: Use "krb5i" to establish NFSv4 state whenever possible" Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Bryan Schumaker <bjschuma@netapp.com>
2013-04-04NFS: Use server-recommended security flavor by default (NFSv3)Chuck Lever
Since commit ec88f28d in 2009, checking if the user-specified flavor is in the server's flavor list has been the source of a few noticeable regressions (now fixed), but there is one that is still vexing. An NFS server can list AUTH_NULL in its flavor list, which suggests a client should try to mount the server with the flavor of the client's choice, but the server will squash all accesses. In some cases, our client fails to mount a server because of this check, when the mount could have proceeded successfully. Skip this check if the user has specified "sec=" on the mount command line. But do consult the server-provided flavor list to choose a security flavor if no sec= option is specified on the mount command. If a server lists Kerberos pseudoflavors before "sys" in its export options, our client now chooses Kerberos over AUTH_UNIX for mount points, when no security flavor is specified by the mount command. This could be surprising to some administrators or users, who would then need to have Kerberos credentials to access the export. Or, a client administrator may not have enabled rpc.gssd. In this case, auth_rpcgss.ko might still be loadable, which is enough for the new logic to choose Kerberos over AUTH_UNIX. But the mount would fail since no GSS context can be created without rpc.gssd running. To retain the use of AUTH_UNIX by default: o The server administrator can ensure that "sys" is listed before Kerberos flavors in its export security options (see exports(5)), o The client administrator can explicitly specify "sec=sys" on its mount command line (see nfs(5)), o The client administrator can use "Sec=sys" in an appropriate section of /etc/nfsmount.conf (see nfsmount.conf(5)), or o The client administrator can blacklist auth_rpcgss.ko. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-02selinux: make security_sb_clone_mnt_opts return an error on context mismatchJeff Layton
I had the following problem reported a while back. If you mount the same filesystem twice using NFSv4 with different contexts, then the second context= option is ignored. For instance: # mount server:/export /mnt/test1 # mount server:/export /mnt/test2 -o context=system_u:object_r:tmp_t:s0 # ls -dZ /mnt/test1 drwxrwxrwt. root root system_u:object_r:nfs_t:s0 /mnt/test1 # ls -dZ /mnt/test2 drwxrwxrwt. root root system_u:object_r:nfs_t:s0 /mnt/test2 When we call into SELinux to set the context of a "cloned" superblock, it will currently just bail out when it notices that we're reusing an existing superblock. Since the existing superblock is already set up and presumably in use, we can't go overwriting its context with the one from the "original" sb. Because of this, the second context= option in this case cannot take effect. This patch fixes this by turning security_sb_clone_mnt_opts into an int return operation. When it finds that the "new" superblock that it has been handed is already set up, it checks to see whether the contexts on the old superblock match it. If it does, then it will just return success, otherwise it'll return -EBUSY and emit a printk to tell the admin why the second mount failed. Note that this patch may cause casualties. The NFSv4 code relies on being able to walk down to an export from the pseudoroot. If you mount filesystems that are nested within one another with different contexts, then this patch will make those mounts fail in new and "exciting" ways. For instance, suppose that /export is a separate filesystem on the server: # mount server:/ /mnt/test1 # mount salusa:/export /mnt/test2 -o context=system_u:object_r:tmp_t:s0 mount.nfs: an incorrect mount option was specified ...with the printk in the ring buffer. Because we *might* eventually walk down to /mnt/test1/export, the mount is denied due to this patch. The second mount needs the pseudoroot superblock, but that's already present with the wrong context. OTOH, if we mount these in the reverse order, then both mounts work, because the pseudoroot superblock created when mounting /export is discarded once that mount is done. If we then however try to walk into that directory, the automount fails for the similar reasons: # cd /mnt/test1/scratch/ -bash: cd: /mnt/test1/scratch: Device or resource busy The story I've gotten from the SELinux folks that I've talked to is that this is desirable behavior. In SELinux-land, mounting the same data under different contexts is wrong -- there can be only one. Cc: Steve Dickson <steved@redhat.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2013-03-29NFS: Use "krb5i" to establish NFSv4 state whenever possibleChuck Lever
Currently our client uses AUTH_UNIX for state management on Kerberos NFS mounts in some cases. For example, if the first mount of a server specifies "sec=sys," the SETCLIENTID operation is performed with AUTH_UNIX. Subsequent mounts using stronger security flavors can not change the flavor used for lease establishment. This might be less security than an administrator was expecting. Dave Noveck's migration issues draft recommends the use of an integrity-protecting security flavor for the SETCLIENTID operation. Let's ignore the mount's sec= setting and use krb5i as the default security flavor for SETCLIENTID. If our client can't establish a GSS context (eg. because it doesn't have a keytab or the server doesn't support Kerberos) we fall back to using AUTH_NULL. For an operation that requires a machine credential (which never represents a particular user) AUTH_NULL is as secure as AUTH_UNIX. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-03-29NFS: Try AUTH_UNIX when PUTROOTFH gets NFS4ERR_WRONGSECChuck Lever
Most NFSv4 servers implement AUTH_UNIX, and administrators will prefer this over AUTH_NULL. It is harmless for our client to try this flavor in addition to the flavors mandated by RFC 3530/5661. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-03-29NFS: Use static list of security flavors during root FH lookup recoveryChuck Lever
If the Linux NFS client receives an NFS4ERR_WRONGSEC error while trying to look up an NFS server's root file handle, it retries the lookup operation with various security flavors to see what flavor the NFS server will accept for pseudo-fs access. The list of flavors the client uses during retry consists only of flavors that are currently registered in the kernel RPC client. This list may not include any GSS pseudoflavors if auth_rpcgss.ko has not yet been loaded. Let's instead use a static list of security flavors that the NFS standard requires the server to implement (RFC 3530bis, section 3.2.1). The RPC client should now be able to load support for these dynamically; if not, they are skipped. Recovery behavior here is prescribed by RFC 3530bis, section 15.33.5: > For LOOKUPP, PUTROOTFH and PUTPUBFH, the client will be unable to > use the SECINFO operation since SECINFO requires a current > filehandle and none exist for these two [sic] operations. Therefore, > the client must iterate through the security triples available at > the client and reattempt the PUTROOTFH or PUTPUBFH operation. In > the unfortunate event none of the MANDATORY security triples are > supported by the client and server, the client SHOULD try using > others that support integrity. Failing that, the client can try > using AUTH_NONE, but because such forms lack integrity checks, > this puts the client at risk. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Cc: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-03-29NFS: Avoid PUTROOTFH when managing leasesChuck Lever
Currently, the compound operation the Linux NFS client sends to the server to confirm a client ID looks like this: { SETCLIENTID_CONFIRM; PUTROOTFH; GETATTR(lease_time) } Once the lease is confirmed, it makes sense to know how long before the client will have to renew it. And, performing these operations in the same compound saves a round trip. Unfortunately, this arrangement assumes that the security flavor used for establishing a client ID can also be used to access the server's pseudo-fs. If the server requires a different security flavor to access its pseudo-fs than it allowed for the client's SETCLIENTID operation, the PUTROOTFH in this compound fails with NFS4ERR_WRONGSEC. Even though the SETCLIENTID_CONFIRM succeeded, our client's trunking detection logic interprets the failure of the compound as a failure by the server to confirm the client ID. As part of server trunking detection, the client then begins another SETCLIENTID pass with the same nfs4_client_id. This fails with NFS4ERR_CLID_INUSE because the first SETCLIENTID/SETCLIENTID_CONFIRM already succeeded in confirming that client ID -- it was the PUTROOTFH operation that caused the SETCLIENTID_CONFIRM compound to fail. To address this issue, separate the "establish client ID" step from the "accessing the server's pseudo-fs root" step. The first access of the server's pseudo-fs may require retrying the PUTROOTFH operation with different security flavors. This access is done in nfs4_proc_get_rootfh(). That leaves the matter of how to retrieve the server's lease time. nfs4_proc_fsinfo() already retrieves the lease time value, though none of its callers do anything with the retrieved value (nor do they mark the lease as "renewed"). Note that NFSv4.1 state recovery invokes nfs4_proc_get_lease_time() using the lease management security flavor. This may cause some heartburn if that security flavor isn't the same as the security flavor the server requires for accessing the pseudo-fs. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Cc: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-03-29NFS: Clean up nfs4_proc_get_rootfhChuck Lever
The long lines with no vertical white space make this function difficult for humans to read. Add a proper documenting comment while we're here. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Cc: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>