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2009-03-18nfsd4: remove unneeded local variableJ. Bruce Fields
We no longer need stidp. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18nfsd4: remove redundant "if" in nfs4_preprocess_stateid_opJ. Bruce Fields
Note that we exit this first big "if" with stp == NULL if and only if we took the first branch; therefore, the second "if" is redundant, and we can just combine the two, simplifying the logic. Reviewed-by: Yang Hongyang <yanghy@cn.fujitsu.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18nfsd4: move check_stateid_generation checkJ. Bruce Fields
No change in behavior. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18nfsd4: trivial preprocess_stateid_op cleanupJ. Bruce Fields
Remove a couple redundant comments, adjust style; no change in behavior. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18nfsd(v2/v3): fix the failure of creation from HPUX clientwengang wang
sometimes HPUX nfs client sends a create request to linux nfs server(v2/v3). the dump of the request is like: obj_attributes mode: value follows set_it: value follows (1) mode: 00 uid: no value set_it: no value (0) gid: value follows set_it: value follows (1) gid: 8030 size: value follows set_it: value follows (1) size: 0 atime: don't change set_it: don't change (0) mtime: don't change set_it: don't change (0) note that mode is 00(havs no rwx privilege even for the owner) and it requires to set size to 0. as current nfsd(v2/v3) implementation, the server does mainly 2 steps: 1) creates the file in mode specified by calling vfs_create(). 2) sets attributes for the file by calling nfsd_setattr(). at step 2), it finally calls file system specific setattr() function which may fail when checking permission because changing size needs WRITE privilege but it has none since mode is 000. for this case, a new file created, we may simply ignore the request of setting size to 0, so that WRITE privilege is not needed and the open succeeds. Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com> -- vfs.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18nfsd: lock state around put client and delegation in nfsd4_cb_recallAlexandros Batsakis
not having the state locked before putting the client/delegation causes a bug. Also removed the comment from the function header about the state being already locked Signed-off-by: Alexandros Batsakis <batsakis@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18nfsd4: use helper for copying delegation filehandleJ. Bruce Fields
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18nfsd4: use helper for copying filehandles for replayJ. Bruce Fields
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18nfsd4: fix misplaced commentJ. Bruce Fields
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18nfsd: clarify exclusive create bitmask result.J. Bruce Fields
The use of |= is confusing--the bitmask is always initialized to zero in this case, so we're effectively just doing an assignment here. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18nfsd : Define NFSD only when FILE_LOCKING is enabledManish Katiyar
Enable NFSD only when FILE_LOCKING is enabled, since we don't want to support NFSD without FILE_LOCKING. Signed-off-by: Manish Katiyar <mkatiyar@gmail.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18NFSD: cleanup for nfs3proc.cQinghuang Feng
MSDOS_SUPER_MAGIC is defined in <linux/magic.h>, so use MSDOS_SUPER_MAGIC directly. Signed-off-by: Qinghuang Feng <qhfeng.kernel@gmail.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18nfsd4: split open/lockowner release codeJ. Bruce Fields
The caller always knows specifically whether it's releasing a lockowner or an openowner, and the code is simpler if we use separate functions (and the apparent recursion is gone). Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18nfsd4: remove a forward declarationJ. Bruce Fields
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18nfsd4: split lockstateid/openstateid release logicJ. Bruce Fields
The flags here attempt to make the code more general, but I find it actually just adds confusion. I think it's clearer to separate the logic for the open and lock cases entirely. And eventually we may want to separate the stateowner and stateid types as well, as many of the fields aren't shared between the lock and open cases. Also move to eliminate forward references. Start with the stateid's. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Reviewed-by: Benny Halevy <bhalevy@panasas.com>
2009-03-17NFSD: provide encode routine for OP_OPENATTRBenny Halevy
Although this operation is unsupported by our implementation we still need to provide an encode routine for it to merely encode its (error) status back in the compound reply. Thanks for Bill Baker at sun.com for testing with the Sun OpenSolaris' client, finding, and reporting this bug at Connectathon 2009. This bug was introduced in 2.6.27 Signed-off-by: Benny Halevy <bhalevy@panasas.com> Cc: stable@kernel.org Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-16Use f_lock to protect f_flagsJonathan Corbet
Traditionally, changes to struct file->f_flags have been done under BKL protection, or with no protection at all. This patch causes all f_flags changes after file open/creation time to be done under protection of f_lock. This allows the removal of some BKL usage and fixes a number of longstanding (if microscopic) races. Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2009-01-27nfsd: only set file_lock.fl_lmops in nfsd4_lockt if a stateowner is foundJeff Layton
nfsd4_lockt does a search for a lockstateowner when building the lock struct to test. If one is found, it'll set fl_owner to it. Regardless of whether that happens, it'll also set fl_lmops. Given that this lock is basically a "lightweight" lock that's just used for checking conflicts, setting fl_lmops is probably not appropriate for it. This behavior exposed a bug in DLM's GETLK implementation where it wasn't clearing out the fields in the file_lock before filling in conflicting lock info. While we were able to fix this in DLM, it still seems pointless and dangerous to set the fl_lmops this way when we may have a NULL lockstateowner. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@pig.fieldses.org>
2009-01-27nfsd: fix cred leak on every rpcJ. Bruce Fields
Since override_creds() took its own reference on new, we need to release our own reference. (Note the put_cred on the return value puts the *old* value of current->creds, not the new passed-in value). Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-27nfsd: fix null dereference on error pathJ. Bruce Fields
We're forgetting to check the return value from groups_alloc(). Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-22fs/Kconfig: move nfsd outAlexey Dobriyan
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-01-07nfsd: last_byte_offsetBenny Halevy
refactor the nfs4 server lock code to use last_byte_offset to compute the last byte covered by the lock. Check for overflow so that the last byte is set to NFS4_MAX_UINT64 if offset + len wraps around. Also, use NFS4_MAX_UINT64 for ~(u64)0 where appropriate. Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-07nfsd: delete wrong file comment from nfsd/nfs4xdr.cMarc Eshel
Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-07nfsd: git rid of nfs4_cb_null_ops declarationBenny Halevy
There's no use for nfs4_cb_null_ops's declaration in fs/nfsd/nfs4callback.c Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-07nfsd: dprint each op status in nfsd4_proc_compoundBenny Halevy
Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-07nfsd: add etoosmall to nfserrnoDean Hildebrand
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-07NFSD: FIDs need to take precedence over UUIDsSteve Dickson
When determining the fsid_type in fh_compose(), the setting of the FID via fsid= export option needs to take precedence over using the UUID device id. Signed-off-by: Steve Dickson <steved@redhat.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-07nfsd: fix double-locks of directory mutexJ. Bruce Fields
A number of nfsd operations depend on the i_mutex to cover more code than just the fsync, so the approach of 4c728ef583b3d8 "add a vfs_fsync helper" doesn't work for nfsd. Revert the parts of those patches that touch nfsd. Note: we can't, however, remove the logic from vfs_fsync that was needed only for the special case of nfsd, because a vfs_fsync(NULL,...) call can still result indirectly from a stackable filesystem that was called by nfsd. (Thanks to Christoph Hellwig for pointing this out.) Reported-by: Eric Sesterhenn <snakebyte@gmx.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-07CRED: Fix NFSD regressionDavid Howells
Fix a regression in NFSD's permission checking introduced by the credentials patches. There are two parts to the problem, both in nfsd_setuser(): (1) The return value of set_groups() is -ve if in error, not 0, and should be checked appropriately. 0 indicates success. (2) The UID to use for fs accesses is in new->fsuid, not new->uid (which is 0). This causes CAP_DAC_OVERRIDE to always be set, rather than being cleared if the UID is anything other than 0 after squashing. Reported-by: J. Bruce Fields <bfields@fieldses.org> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-07nfsd: Ensure nfsv4 calls the underlying filesystem on LOCKTJ. Bruce Fields
Since nfsv4 allows LOCKT without an open, but the ->lock() method is a file method, we fake up a struct file in the nfsv4 code with just the fields we need initialized. But we forgot to initialize the file operations, with the result that LOCKT never results in a call to the filesystem's ->lock() method (if it exists). We could just add that one more initialization. But this hack of faking up a struct file with only some fields initialized seems the kind of thing that might cause more problems in the future. We should either do an open and get a real struct file, or make lock-testing an inode (not a file) method. This patch does the former. Reported-by: Marc Eshel <eshel@almaden.ibm.com> Tested-by: Marc Eshel <eshel@almaden.ibm.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NFSD: Add documenting comments for nfsctl interfaceChuck Lever
Document the NFSD sysctl interface laid out in fs/nfsd/nfsctl.c. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NFSD: Replace open-coded integer with macroChuck Lever
Clean up: Instead of open-coding 2049, use the NFS_PORT macro. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NFSD: Fix a handful of coding style issues in write_filehandle()Chuck Lever
Clean up: follow kernel coding style. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NFSD: clean up failover sysctl function namingChuck Lever
Clean up: Rename recently-added failover functions to match the naming convention in fs/nfsd/nfsctl.c. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06nfsd: Fix leaked memory in nfs4_make_rec_clidnameKrishna Kumar
cksum.data is not freed up in one error case. Compile tested. Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06nfsd: Minor cleanup of find_stateidKrishna Kumar
Minor cleanup/rewrite of find_stateid. Compile tested. Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06nfsd: update fh_verify descriptionJ. Bruce Fields
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-05add a vfs_fsync helperChristoph Hellwig
Fsync currently has a fdatawrite/fdatawait pair around the method call, and a mutex_lock/unlock of the inode mutex. All callers of fsync have to duplicate this, but we have a few and most of them don't quite get it right. This patch adds a new vfs_fsync that takes care of this. It's a little more complicated as usual as ->fsync might get a NULL file pointer and just a dentry from nfsd, but otherwise gets afile and we want to take the mapping and file operations from it when it is there. Notes on the fsync callers: - ecryptfs wasn't calling filemap_fdatawrite / filemap_fdatawait on the lower file - coda wasn't calling filemap_fdatawrite / filemap_fdatawait on the host file, and returning 0 when ->fsync was missing - shm wasn't calling either filemap_fdatawrite / filemap_fdatawait nor taking i_mutex. Now given that shared memory doesn't have disk backing not doing anything in fsync seems fine and I left it out of the vfs_fsync conversion for now, but in that case we might just not pass it through to the lower file at all but just call the no-op simple_sync_file directly. [and now actually export vfs_fsync] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-05inode->i_op is never NULLAl Viro
We used to have rather schizophrenic set of checks for NULL ->i_op even though it had been eliminated years ago. You'd need to go out of your way to set it to NULL explicitly _and_ a bunch of code would die on such inodes anyway. After killing two remaining places that still did that bogosity, all that crap can go away. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-30Merge branch 'devel' into nextTrond Myklebust
2008-12-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1429 commits) net: Allow dependancies of FDDI & Tokenring to be modular. igb: Fix build warning when DCA is disabled. net: Fix warning fallout from recent NAPI interface changes. gro: Fix potential use after free sfc: If AN is enabled, always read speed/duplex from the AN advertising bits sfc: When disabling the NIC, close the device rather than unregistering it sfc: SFT9001: Add cable diagnostics sfc: Add support for multiple PHY self-tests sfc: Merge top-level functions for self-tests sfc: Clean up PHY mode management in loopback self-test sfc: Fix unreliable link detection in some loopback modes sfc: Generate unique names for per-NIC workqueues 802.3ad: use standard ethhdr instead of ad_header 802.3ad: generalize out mac address initializer 802.3ad: initialize ports LACPDU from const initializer 802.3ad: remove typedef around ad_system 802.3ad: turn ports is_individual into a bool 802.3ad: turn ports is_enabled into a bool 802.3ad: make ntt bool ixgbe: Fix set_ringparam in ixgbe to use the same memory pools. ... Fixed trivial IPv4/6 address printing conflicts in fs/cifs/connect.c due to the conversion to %pI (in this networking merge) and the addition of doing IPv6 addresses (from the earlier merge of CIFS).
2008-12-23nfsd: support callbacks with gss flavorsOlga Kornievskaia
This patch adds server-side support for callbacks other than AUTH_SYS. Signed-off-by: Olga Kornievskaia <aglo@citi.umich.edu> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-12-23rpc: pass target name down to rpc level on callbacksOlga Kornievskaia
The rpc client needs to know the principal that the setclientid was done as, so it can tell gssd who to authenticate to. Signed-off-by: Olga Kornievskaia <aglo@citi.umich.edu> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-12-23nfsd: pass client principal name in rsc downcallOlga Kornievskaia
Two principals are involved in krb5 authentication: the target, who we authenticate *to* (normally the name of the server, like nfs/server.citi.umich.edu@CITI.UMICH.EDU), and the source, we we authenticate *as* (normally a user, like bfields@UMICH.EDU) In the case of NFSv4 callbacks, the target of the callback should be the source of the client's setclientid call, and the source should be the nfs server's own principal. Therefore we allow svcgssd to pass down the name of the principal that just authenticated, so that on setclientid we can store that principal name with the new client, to be used later on callbacks. Signed-off-by: Olga Kornievskaia <aglo@citi.umich.edu> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-12-15Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/e1000e/ich8lan.c
2008-12-04Merge branch 'master' into nextJames Morris
Conflicts: fs/nfsd/nfs4recover.c Manually fixed above to use new creds API functions, e.g. nfs4_save_creds(). Signed-off-by: James Morris <jmorris@namei.org>
2008-11-24nfsd: use of unitialized list head on error exit in nfs4recover.cJ. Bruce Fields
Thanks to Matthew Dodd for this bug report: A file label issue while running SELinux in MLS mode provoked the following bug, which is a result of use before init on a 'struct list_head'. In nfsd4_list_rec_dir() if the call to dentry_open() fails the 'goto out' skips INIT_LIST_HEAD() which results in the normally improbable case where list_entry() returns NULL. Trace follows. NFSD: Using /var/lib/nfs/v4recovery as the NFSv4 state recovery directory SELinux: Context unconfined_t:object_r:var_lib_nfs_t:s0 is not valid (left unmapped). type=1400 audit(1227298063.609:282): avc: denied { read } for pid=1890 comm="rpc.nfsd" name="v4recovery" dev=dm-0 ino=148726 scontext=system_u:system_r:nfsd_t:s0-s15:c0.c1023 tcontext=system_u:object_r:unlabeled_t:s15:c0.c1023 tclass=dir BUG: unable to handle kernel NULL pointer dereference at 00000004 IP: [<c050894e>] list_del+0x6/0x60 *pde = 0d9ce067 *pte = 00000000 Oops: 0000 [#1] SMP Modules linked in: nfsd lockd nfs_acl auth_rpcgss exportfs autofs4 sunrpc ipv6 dm_multipath scsi_dh ppdev parport_pc sg parport floppy ata_piix pata_acpi ata_generic libata pcnet32 i2c_piix4 mii pcspkr i2c_core dm_snapshot dm_zero dm_mirror dm_log dm_mod BusLogic sd_mod scsi_mod crc_t10dif ext3 jbd mbcache uhci_hcd ohci_hcd ehci_hcd [last unloaded: microcode] Pid: 1890, comm: rpc.nfsd Not tainted (2.6.27.5-37.fc9.i686 #1) EIP: 0060:[<c050894e>] EFLAGS: 00010217 CPU: 0 EIP is at list_del+0x6/0x60 EAX: 00000000 EBX: 00000000 ECX: 00000000 EDX: cd99e480 ESI: cf9caed8 EDI: 00000000 EBP: cf9caebc ESP: cf9caeb8 DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 Process rpc.nfsd (pid: 1890, ti=cf9ca000 task=cf4de580 task.ti=cf9ca000) Stack: 00000000 cf9caef0 d0a9f139 c0496d04 d0a9f217 fffffff3 00000000 00000000 00000000 00000000 cf32b220 00000000 00000008 00000801 cf9caefc d0a9f193 00000000 cf9caf08 d0a9b6ea 00000000 cf9caf1c d0a874f2 cf9c3004 00000008 Call Trace: [<d0a9f139>] ? nfsd4_list_rec_dir+0xf3/0x13a [nfsd] [<c0496d04>] ? do_path_lookup+0x12d/0x175 [<d0a9f217>] ? load_recdir+0x0/0x26 [nfsd] [<d0a9f193>] ? nfsd4_recdir_load+0x13/0x34 [nfsd] [<d0a9b6ea>] ? nfs4_state_start+0x2a/0xc5 [nfsd] [<d0a874f2>] ? nfsd_svc+0x51/0xff [nfsd] [<d0a87f2d>] ? write_svc+0x0/0x1e [nfsd] [<d0a87f48>] ? write_svc+0x1b/0x1e [nfsd] [<d0a87854>] ? nfsctl_transaction_write+0x3a/0x61 [nfsd] [<c04b6a4e>] ? sys_nfsservctl+0x116/0x154 [<c04975c1>] ? putname+0x24/0x2f [<c04975c1>] ? putname+0x24/0x2f [<c048d49f>] ? do_sys_open+0xad/0xb7 [<c048d337>] ? filp_close+0x50/0x5a [<c048d4eb>] ? sys_open+0x1e/0x26 [<c0403cca>] ? syscall_call+0x7/0xb [<c064007b>] ? init_cyrix+0x185/0x490 ======================= Code: 75 e1 8b 53 08 8d 4b 04 8d 46 04 e8 75 00 00 00 8b 53 10 8d 4b 0c 8d 46 0c e8 67 00 00 00 5b 5e 5f 5d c3 90 90 55 89 e5 53 89 c3 <8b> 40 04 8b 00 39 d8 74 16 50 53 68 3e d6 6f c0 6a 30 68 78 d6 EIP: [<c050894e>] list_del+0x6/0x60 SS:ESP 0068:cf9caeb8 ---[ end trace a89c4ad091c4ad53 ]--- Cc: Matthew N. Dodd <Matthew.Dodd@spart.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-11-24nfsd: clean up grace period on early exitJ. Bruce Fields
If nfsd was shut down before the grace period ended, we could end up with a freed object still on grace_list. Thanks to Jeff Moyer for reporting the resulting list corruption warnings. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Tested-by: Jeff Moyer <jmoyer@redhat.com>
2008-11-14Merge branch 'master' into nextJames Morris
Conflicts: security/keys/internal.h security/keys/process_keys.c security/keys/request_key.c Fixed conflicts above by using the non 'tsk' versions. Signed-off-by: James Morris <jmorris@namei.org>
2008-11-14CRED: Differentiate objective and effective subjective credentials on a taskDavid Howells
Differentiate the objective and real subjective credentials from the effective subjective credentials on a task by introducing a second credentials pointer into the task_struct. task_struct::real_cred then refers to the objective and apparent real subjective credentials of a task, as perceived by the other tasks in the system. task_struct::cred then refers to the effective subjective credentials of a task, as used by that task when it's actually running. These are not visible to the other tasks in the system. __task_cred(task) then refers to the objective/real credentials of the task in question. current_cred() refers to the effective subjective credentials of the current task. prepare_creds() uses the objective creds as a base and commit_creds() changes both pointers in the task_struct (indeed commit_creds() requires them to be the same). override_creds() and revert_creds() change the subjective creds pointer only, and the former returns the old subjective creds. These are used by NFSD, faccessat() and do_coredump(), and will by used by CacheFiles. In SELinux, current_has_perm() is provided as an alternative to task_has_perm(). This uses the effective subjective context of current, whereas task_has_perm() uses the objective/real context of the subject. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>