1. 14 11月, 2008 40 次提交
    • J
      Merge branch 'master' into next · 2b828925
      James Morris 提交于
      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: NJames Morris <jmorris@namei.org>
      2b828925
    • D
      CRED: Allow kernel services to override LSM settings for task actions · 3a3b7ce9
      David Howells 提交于
      Allow kernel services to override LSM settings appropriate to the actions
      performed by a task by duplicating a set of credentials, modifying it and then
      using task_struct::cred to point to it when performing operations on behalf of
      a task.
      
      This is used, for example, by CacheFiles which has to transparently access the
      cache on behalf of a process that thinks it is doing, say, NFS accesses with a
      potentially inappropriate (with respect to accessing the cache) set of
      credentials.
      
      This patch provides two LSM hooks for modifying a task security record:
      
       (*) security_kernel_act_as() which allows modification of the security datum
           with which a task acts on other objects (most notably files).
      
       (*) security_kernel_create_files_as() which allows modification of the
           security datum that is used to initialise the security data on a file that
           a task creates.
      
      The patch also provides four new credentials handling functions, which wrap the
      LSM functions:
      
       (1) prepare_kernel_cred()
      
           Prepare a set of credentials for a kernel service to use, based either on
           a daemon's credentials or on init_cred.  All the keyrings are cleared.
      
       (2) set_security_override()
      
           Set the LSM security ID in a set of credentials to a specific security
           context, assuming permission from the LSM policy.
      
       (3) set_security_override_from_ctx()
      
           As (2), but takes the security context as a string.
      
       (4) set_create_files_as()
      
           Set the file creation LSM security ID in a set of credentials to be the
           same as that on a particular inode.
      
      Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> [Smack changes]
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      3a3b7ce9
    • D
      CRED: Add a kernel_service object class to SELinux · 1bfdc75a
      David Howells 提交于
      Add a 'kernel_service' object class to SELinux and give this object class two
      access vectors: 'use_as_override' and 'create_files_as'.
      
      The first vector is used to grant a process the right to nominate an alternate
      process security ID for the kernel to use as an override for the SELinux
      subjective security when accessing stuff on behalf of another process.
      
      For example, CacheFiles when accessing the cache on behalf on a process
      accessing an NFS file needs to use a subjective security ID appropriate to the
      cache rather then the one the calling process is using.  The cachefilesd
      daemon will nominate the security ID to be used.
      
      The second vector is used to grant a process the right to nominate a file
      creation label for a kernel service to use.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      1bfdc75a
    • D
      CRED: Differentiate objective and effective subjective credentials on a task · 3b11a1de
      David Howells 提交于
      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: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      3b11a1de
    • D
      CRED: Documentation · 98870ab0
      David Howells 提交于
      Document credentials and the new credentials API.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      98870ab0
    • D
      CRED: Use creds in file structs · d76b0d9b
      David Howells 提交于
      Attach creds to file structs and discard f_uid/f_gid.
      
      file_operations::open() methods (such as hppfs_open()) should use file->f_cred
      rather than current_cred().  At the moment file->f_cred will be current_cred()
      at this point.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      d76b0d9b
    • D
      CRED: Prettify commoncap.c · 1d045980
      David Howells 提交于
      Prettify commoncap.c.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      1d045980
    • D
      CRED: Make execve() take advantage of copy-on-write credentials · a6f76f23
      David Howells 提交于
      Make execve() take advantage of copy-on-write credentials, allowing it to set
      up the credentials in advance, and then commit the whole lot after the point
      of no return.
      
      This patch and the preceding patches have been tested with the LTP SELinux
      testsuite.
      
      This patch makes several logical sets of alteration:
      
       (1) execve().
      
           The credential bits from struct linux_binprm are, for the most part,
           replaced with a single credentials pointer (bprm->cred).  This means that
           all the creds can be calculated in advance and then applied at the point
           of no return with no possibility of failure.
      
           I would like to replace bprm->cap_effective with:
      
      	cap_isclear(bprm->cap_effective)
      
           but this seems impossible due to special behaviour for processes of pid 1
           (they always retain their parent's capability masks where normally they'd
           be changed - see cap_bprm_set_creds()).
      
           The following sequence of events now happens:
      
           (a) At the start of do_execve, the current task's cred_exec_mutex is
           	 locked to prevent PTRACE_ATTACH from obsoleting the calculation of
           	 creds that we make.
      
           (a) prepare_exec_creds() is then called to make a copy of the current
           	 task's credentials and prepare it.  This copy is then assigned to
           	 bprm->cred.
      
        	 This renders security_bprm_alloc() and security_bprm_free()
           	 unnecessary, and so they've been removed.
      
           (b) The determination of unsafe execution is now performed immediately
           	 after (a) rather than later on in the code.  The result is stored in
           	 bprm->unsafe for future reference.
      
           (c) prepare_binprm() is called, possibly multiple times.
      
           	 (i) This applies the result of set[ug]id binaries to the new creds
           	     attached to bprm->cred.  Personality bit clearance is recorded,
           	     but now deferred on the basis that the exec procedure may yet
           	     fail.
      
               (ii) This then calls the new security_bprm_set_creds().  This should
      	     calculate the new LSM and capability credentials into *bprm->cred.
      
      	     This folds together security_bprm_set() and parts of
      	     security_bprm_apply_creds() (these two have been removed).
      	     Anything that might fail must be done at this point.
      
               (iii) bprm->cred_prepared is set to 1.
      
      	     bprm->cred_prepared is 0 on the first pass of the security
      	     calculations, and 1 on all subsequent passes.  This allows SELinux
      	     in (ii) to base its calculations only on the initial script and
      	     not on the interpreter.
      
           (d) flush_old_exec() is called to commit the task to execution.  This
           	 performs the following steps with regard to credentials:
      
      	 (i) Clear pdeath_signal and set dumpable on certain circumstances that
      	     may not be covered by commit_creds().
      
               (ii) Clear any bits in current->personality that were deferred from
                   (c.i).
      
           (e) install_exec_creds() [compute_creds() as was] is called to install the
           	 new credentials.  This performs the following steps with regard to
           	 credentials:
      
               (i) Calls security_bprm_committing_creds() to apply any security
                   requirements, such as flushing unauthorised files in SELinux, that
                   must be done before the credentials are changed.
      
      	     This is made up of bits of security_bprm_apply_creds() and
      	     security_bprm_post_apply_creds(), both of which have been removed.
      	     This function is not allowed to fail; anything that might fail
      	     must have been done in (c.ii).
      
               (ii) Calls commit_creds() to apply the new credentials in a single
                   assignment (more or less).  Possibly pdeath_signal and dumpable
                   should be part of struct creds.
      
      	 (iii) Unlocks the task's cred_replace_mutex, thus allowing
      	     PTRACE_ATTACH to take place.
      
               (iv) Clears The bprm->cred pointer as the credentials it was holding
                   are now immutable.
      
               (v) Calls security_bprm_committed_creds() to apply any security
                   alterations that must be done after the creds have been changed.
                   SELinux uses this to flush signals and signal handlers.
      
           (f) If an error occurs before (d.i), bprm_free() will call abort_creds()
           	 to destroy the proposed new credentials and will then unlock
           	 cred_replace_mutex.  No changes to the credentials will have been
           	 made.
      
       (2) LSM interface.
      
           A number of functions have been changed, added or removed:
      
           (*) security_bprm_alloc(), ->bprm_alloc_security()
           (*) security_bprm_free(), ->bprm_free_security()
      
           	 Removed in favour of preparing new credentials and modifying those.
      
           (*) security_bprm_apply_creds(), ->bprm_apply_creds()
           (*) security_bprm_post_apply_creds(), ->bprm_post_apply_creds()
      
           	 Removed; split between security_bprm_set_creds(),
           	 security_bprm_committing_creds() and security_bprm_committed_creds().
      
           (*) security_bprm_set(), ->bprm_set_security()
      
           	 Removed; folded into security_bprm_set_creds().
      
           (*) security_bprm_set_creds(), ->bprm_set_creds()
      
           	 New.  The new credentials in bprm->creds should be checked and set up
           	 as appropriate.  bprm->cred_prepared is 0 on the first call, 1 on the
           	 second and subsequent calls.
      
           (*) security_bprm_committing_creds(), ->bprm_committing_creds()
           (*) security_bprm_committed_creds(), ->bprm_committed_creds()
      
           	 New.  Apply the security effects of the new credentials.  This
           	 includes closing unauthorised files in SELinux.  This function may not
           	 fail.  When the former is called, the creds haven't yet been applied
           	 to the process; when the latter is called, they have.
      
       	 The former may access bprm->cred, the latter may not.
      
       (3) SELinux.
      
           SELinux has a number of changes, in addition to those to support the LSM
           interface changes mentioned above:
      
           (a) The bprm_security_struct struct has been removed in favour of using
           	 the credentials-under-construction approach.
      
           (c) flush_unauthorized_files() now takes a cred pointer and passes it on
           	 to inode_has_perm(), file_has_perm() and dentry_open().
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      a6f76f23
    • D
      CRED: Inaugurate COW credentials · d84f4f99
      David Howells 提交于
      Inaugurate copy-on-write credentials management.  This uses RCU to manage the
      credentials pointer in the task_struct with respect to accesses by other tasks.
      A process may only modify its own credentials, and so does not need locking to
      access or modify its own credentials.
      
      A mutex (cred_replace_mutex) is added to the task_struct to control the effect
      of PTRACE_ATTACHED on credential calculations, particularly with respect to
      execve().
      
      With this patch, the contents of an active credentials struct may not be
      changed directly; rather a new set of credentials must be prepared, modified
      and committed using something like the following sequence of events:
      
      	struct cred *new = prepare_creds();
      	int ret = blah(new);
      	if (ret < 0) {
      		abort_creds(new);
      		return ret;
      	}
      	return commit_creds(new);
      
      There are some exceptions to this rule: the keyrings pointed to by the active
      credentials may be instantiated - keyrings violate the COW rule as managing
      COW keyrings is tricky, given that it is possible for a task to directly alter
      the keys in a keyring in use by another task.
      
      To help enforce this, various pointers to sets of credentials, such as those in
      the task_struct, are declared const.  The purpose of this is compile-time
      discouragement of altering credentials through those pointers.  Once a set of
      credentials has been made public through one of these pointers, it may not be
      modified, except under special circumstances:
      
        (1) Its reference count may incremented and decremented.
      
        (2) The keyrings to which it points may be modified, but not replaced.
      
      The only safe way to modify anything else is to create a replacement and commit
      using the functions described in Documentation/credentials.txt (which will be
      added by a later patch).
      
      This patch and the preceding patches have been tested with the LTP SELinux
      testsuite.
      
      This patch makes several logical sets of alteration:
      
       (1) execve().
      
           This now prepares and commits credentials in various places in the
           security code rather than altering the current creds directly.
      
       (2) Temporary credential overrides.
      
           do_coredump() and sys_faccessat() now prepare their own credentials and
           temporarily override the ones currently on the acting thread, whilst
           preventing interference from other threads by holding cred_replace_mutex
           on the thread being dumped.
      
           This will be replaced in a future patch by something that hands down the
           credentials directly to the functions being called, rather than altering
           the task's objective credentials.
      
       (3) LSM interface.
      
           A number of functions have been changed, added or removed:
      
           (*) security_capset_check(), ->capset_check()
           (*) security_capset_set(), ->capset_set()
      
           	 Removed in favour of security_capset().
      
           (*) security_capset(), ->capset()
      
           	 New.  This is passed a pointer to the new creds, a pointer to the old
           	 creds and the proposed capability sets.  It should fill in the new
           	 creds or return an error.  All pointers, barring the pointer to the
           	 new creds, are now const.
      
           (*) security_bprm_apply_creds(), ->bprm_apply_creds()
      
           	 Changed; now returns a value, which will cause the process to be
           	 killed if it's an error.
      
           (*) security_task_alloc(), ->task_alloc_security()
      
           	 Removed in favour of security_prepare_creds().
      
           (*) security_cred_free(), ->cred_free()
      
           	 New.  Free security data attached to cred->security.
      
           (*) security_prepare_creds(), ->cred_prepare()
      
           	 New. Duplicate any security data attached to cred->security.
      
           (*) security_commit_creds(), ->cred_commit()
      
           	 New. Apply any security effects for the upcoming installation of new
           	 security by commit_creds().
      
           (*) security_task_post_setuid(), ->task_post_setuid()
      
           	 Removed in favour of security_task_fix_setuid().
      
           (*) security_task_fix_setuid(), ->task_fix_setuid()
      
           	 Fix up the proposed new credentials for setuid().  This is used by
           	 cap_set_fix_setuid() to implicitly adjust capabilities in line with
           	 setuid() changes.  Changes are made to the new credentials, rather
           	 than the task itself as in security_task_post_setuid().
      
           (*) security_task_reparent_to_init(), ->task_reparent_to_init()
      
           	 Removed.  Instead the task being reparented to init is referred
           	 directly to init's credentials.
      
      	 NOTE!  This results in the loss of some state: SELinux's osid no
      	 longer records the sid of the thread that forked it.
      
           (*) security_key_alloc(), ->key_alloc()
           (*) security_key_permission(), ->key_permission()
      
           	 Changed.  These now take cred pointers rather than task pointers to
           	 refer to the security context.
      
       (4) sys_capset().
      
           This has been simplified and uses less locking.  The LSM functions it
           calls have been merged.
      
       (5) reparent_to_kthreadd().
      
           This gives the current thread the same credentials as init by simply using
           commit_thread() to point that way.
      
       (6) __sigqueue_alloc() and switch_uid()
      
           __sigqueue_alloc() can't stop the target task from changing its creds
           beneath it, so this function gets a reference to the currently applicable
           user_struct which it then passes into the sigqueue struct it returns if
           successful.
      
           switch_uid() is now called from commit_creds(), and possibly should be
           folded into that.  commit_creds() should take care of protecting
           __sigqueue_alloc().
      
       (7) [sg]et[ug]id() and co and [sg]et_current_groups.
      
           The set functions now all use prepare_creds(), commit_creds() and
           abort_creds() to build and check a new set of credentials before applying
           it.
      
           security_task_set[ug]id() is called inside the prepared section.  This
           guarantees that nothing else will affect the creds until we've finished.
      
           The calling of set_dumpable() has been moved into commit_creds().
      
           Much of the functionality of set_user() has been moved into
           commit_creds().
      
           The get functions all simply access the data directly.
      
       (8) security_task_prctl() and cap_task_prctl().
      
           security_task_prctl() has been modified to return -ENOSYS if it doesn't
           want to handle a function, or otherwise return the return value directly
           rather than through an argument.
      
           Additionally, cap_task_prctl() now prepares a new set of credentials, even
           if it doesn't end up using it.
      
       (9) Keyrings.
      
           A number of changes have been made to the keyrings code:
      
           (a) switch_uid_keyring(), copy_keys(), exit_keys() and suid_keys() have
           	 all been dropped and built in to the credentials functions directly.
           	 They may want separating out again later.
      
           (b) key_alloc() and search_process_keyrings() now take a cred pointer
           	 rather than a task pointer to specify the security context.
      
           (c) copy_creds() gives a new thread within the same thread group a new
           	 thread keyring if its parent had one, otherwise it discards the thread
           	 keyring.
      
           (d) The authorisation key now points directly to the credentials to extend
           	 the search into rather pointing to the task that carries them.
      
           (e) Installing thread, process or session keyrings causes a new set of
           	 credentials to be created, even though it's not strictly necessary for
           	 process or session keyrings (they're shared).
      
      (10) Usermode helper.
      
           The usermode helper code now carries a cred struct pointer in its
           subprocess_info struct instead of a new session keyring pointer.  This set
           of credentials is derived from init_cred and installed on the new process
           after it has been cloned.
      
           call_usermodehelper_setup() allocates the new credentials and
           call_usermodehelper_freeinfo() discards them if they haven't been used.  A
           special cred function (prepare_usermodeinfo_creds()) is provided
           specifically for call_usermodehelper_setup() to call.
      
           call_usermodehelper_setkeys() adjusts the credentials to sport the
           supplied keyring as the new session keyring.
      
      (11) SELinux.
      
           SELinux has a number of changes, in addition to those to support the LSM
           interface changes mentioned above:
      
           (a) selinux_setprocattr() no longer does its check for whether the
           	 current ptracer can access processes with the new SID inside the lock
           	 that covers getting the ptracer's SID.  Whilst this lock ensures that
           	 the check is done with the ptracer pinned, the result is only valid
           	 until the lock is released, so there's no point doing it inside the
           	 lock.
      
      (12) is_single_threaded().
      
           This function has been extracted from selinux_setprocattr() and put into
           a file of its own in the lib/ directory as join_session_keyring() now
           wants to use it too.
      
           The code in SELinux just checked to see whether a task shared mm_structs
           with other tasks (CLONE_VM), but that isn't good enough.  We really want
           to know if they're part of the same thread group (CLONE_THREAD).
      
      (13) nfsd.
      
           The NFS server daemon now has to use the COW credentials to set the
           credentials it is going to use.  It really needs to pass the credentials
           down to the functions it calls, but it can't do that until other patches
           in this series have been applied.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NJames Morris <jmorris@namei.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      d84f4f99
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      CRED: Pass credentials through dentry_open() · 745ca247
      David Howells 提交于
      Pass credentials through dentry_open() so that the COW creds patch can have
      SELinux's flush_unauthorized_files() pass the appropriate creds back to itself
      when it opens its null chardev.
      
      The security_dentry_open() call also now takes a creds pointer, as does the
      dentry_open hook in struct security_operations.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NJames Morris <jmorris@namei.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      745ca247
    • D
      CRED: Make inode_has_perm() and file_has_perm() take a cred pointer · 88e67f3b
      David Howells 提交于
      Make inode_has_perm() and file_has_perm() take a cred pointer rather than a
      task pointer.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      88e67f3b
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      CRED: Rename is_single_threaded() to is_wq_single_threaded() · 6cc88bc4
      David Howells 提交于
      Rename is_single_threaded() to is_wq_single_threaded() so that a new
      is_single_threaded() can be created that refers to tasks rather than
      waitqueues.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      6cc88bc4
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      CRED: Separate per-task-group keyrings from signal_struct · bb952bb9
      David Howells 提交于
      Separate per-task-group keyrings from signal_struct and dangle their anchor
      from the cred struct rather than the signal_struct.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      bb952bb9
    • D
      CRED: Wrap access to SELinux's task SID · 275bb41e
      David Howells 提交于
      Wrap access to SELinux's task SID, using task_sid() and current_sid() as
      appropriate.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NJames Morris <jmorris@namei.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      275bb41e
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      CRED: Use RCU to access another task's creds and to release a task's own creds · c69e8d9c
      David Howells 提交于
      Use RCU to access another task's creds and to release a task's own creds.
      This means that it will be possible for the credentials of a task to be
      replaced without another task (a) requiring a full lock to read them, and (b)
      seeing deallocated memory.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      c69e8d9c
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      CRED: Wrap current->cred and a few other accessors · 86a264ab
      David Howells 提交于
      Wrap current->cred and a few other accessors to hide their actual
      implementation.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      86a264ab
    • D
      CRED: Detach the credentials from task_struct · f1752eec
      David Howells 提交于
      Detach the credentials from task_struct, duplicating them in copy_process()
      and releasing them in __put_task_struct().
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      f1752eec
    • D
      CRED: Separate task security context from task_struct · b6dff3ec
      David Howells 提交于
      Separate the task security context from task_struct.  At this point, the
      security data is temporarily embedded in the task_struct with two pointers
      pointing to it.
      
      Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in
      entry.S via asm-offsets.
      
      With comment fixes Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      b6dff3ec
    • D
      CRED: Constify the kernel_cap_t arguments to the capset LSM hooks · 15a2460e
      David Howells 提交于
      Constify the kernel_cap_t arguments to the capset LSM hooks.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Acked-by: NJames Morris <jmorris@namei.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      15a2460e
    • D
      CRED: Neuter sys_capset() · 1cdcbec1
      David Howells 提交于
      Take away the ability for sys_capset() to affect processes other than current.
      
      This means that current will not need to lock its own credentials when reading
      them against interference by other processes.
      
      This has effectively been the case for a while anyway, since:
      
       (1) Without LSM enabled, sys_capset() is disallowed.
      
       (2) With file-based capabilities, sys_capset() is neutered.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Acked-by: NAndrew G. Morgan <morgan@kernel.org>
      Acked-by: NJames Morris <jmorris@namei.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      1cdcbec1
    • D
      KEYS: Alter use of key instantiation link-to-keyring argument · 8bbf4976
      David Howells 提交于
      Alter the use of the key instantiation and negation functions' link-to-keyring
      arguments.  Currently this specifies a keyring in the target process to link
      the key into, creating the keyring if it doesn't exist.  This, however, can be
      a problem for copy-on-write credentials as it means that the instantiating
      process can alter the credentials of the requesting process.
      
      This patch alters the behaviour such that:
      
       (1) If keyctl_instantiate_key() or keyctl_negate_key() are given a specific
           keyring by ID (ringid >= 0), then that keyring will be used.
      
       (2) If keyctl_instantiate_key() or keyctl_negate_key() are given one of the
           special constants that refer to the requesting process's keyrings
           (KEY_SPEC_*_KEYRING, all <= 0), then:
      
           (a) If sys_request_key() was given a keyring to use (destringid) then the
           	 key will be attached to that keyring.
      
           (b) If sys_request_key() was given a NULL keyring, then the key being
           	 instantiated will be attached to the default keyring as set by
           	 keyctl_set_reqkey_keyring().
      
       (3) No extra link will be made.
      
      Decision point (1) follows current behaviour, and allows those instantiators
      who've searched for a specifically named keyring in the requestor's keyring so
      as to partition the keys by type to still have their named keyrings.
      
      Decision point (2) allows the requestor to make sure that the key or keys that
      get produced by request_key() go where they want, whilst allowing the
      instantiator to request that the key is retained.  This is mainly useful for
      situations where the instantiator makes a secondary request, the key for which
      should be retained by the initial requestor:
      
      	+-----------+        +--------------+        +--------------+
      	|           |        |              |        |              |
      	| Requestor |------->| Instantiator |------->| Instantiator |
      	|           |        |              |        |              |
      	+-----------+        +--------------+        +--------------+
      	           request_key()           request_key()
      
      This might be useful, for example, in Kerberos, where the requestor requests a
      ticket, and then the ticket instantiator requests the TGT, which someone else
      then has to go and fetch.  The TGT, however, should be retained in the
      keyrings of the requestor, not the first instantiator.  To make this explict
      an extra special keyring constant is also added.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      8bbf4976
    • D
      KEYS: Disperse linux/key_ui.h · e9e349b0
      David Howells 提交于
      Disperse the bits of linux/key_ui.h as the reason they were put here (keyfs)
      didn't get in.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      e9e349b0
    • D
      CRED: Wrap task credential accesses in the core kernel · 76aac0e9
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: linux-audit@redhat.com
      Cc: containers@lists.linux-foundation.org
      Cc: linux-mm@kvack.org
      Signed-off-by: NJames Morris <jmorris@namei.org>
      76aac0e9
    • D
      CRED: Wrap task credential accesses in the capabilities code · b103c598
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: Andrew G. Morgan <morgan@kernel.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      b103c598
    • D
      CRED: Wrap task credential accesses in the key management code · 47d804bf
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      47d804bf
    • D
      CRED: Wrap task credential accesses in the networking subsystem · 8192b0c4
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: netdev@vger.kernel.org
      Signed-off-by: NJames Morris <jmorris@namei.org>
      8192b0c4
    • D
      CRED: Wrap task credential accesses in the UNIX socket protocol · 19d65624
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: netdev@vger.kernel.org
      Signed-off-by: NJames Morris <jmorris@namei.org>
      19d65624
    • D
      CRED: Wrap task credential accesses in the SunRPC protocol · 8f419402
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
      Cc: J. Bruce Fields <bfields@fieldses.org>
      Cc: Neil Brown <neilb@suse.de>
      Cc: linux-nfs@vger.kernel.org
      Signed-off-by: NJames Morris <jmorris@namei.org>
      8f419402
    • D
      CRED: Wrap task credential accesses in the ROSE protocol · c2a2b8d3
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Acked-by: NRalf Baechle <ralf@linux-mips.org>
      Cc: linux-hams@vger.kernel.org
      Signed-off-by: NJames Morris <jmorris@namei.org>
      c2a2b8d3
    • D
      CRED: Wrap task credential accesses in the netrom protocol · ba95b235
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Acked-by: NRalf Baechle <ralf@linux-mips.org>
      Cc: linux-hams@vger.kernel.org
      Signed-off-by: NJames Morris <jmorris@namei.org>
      ba95b235
    • D
      CRED: Wrap task credential accesses in the IPv6 protocol · f82b3590
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: netdev@vger.kernel.org
      Signed-off-by: NJames Morris <jmorris@namei.org>
      f82b3590
    • D
      CRED: Wrap task credential accesses in the AX25 protocol · 73400407
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Acked-by: NRalf Baechle <ralf@linux-mips.org>
      Cc: linux-hams@vger.kernel.org
      Signed-off-by: NJames Morris <jmorris@namei.org>
      73400407
    • D
      CRED: Wrap task credential accesses in the SYSV IPC subsystem · 414c0708
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      414c0708
    • D
      CRED: Wrap task credential accesses in the filesystem subsystem · da9592ed
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      da9592ed
    • D
      CRED: Wrap task credential accesses in the XFS filesystem · 82ab8ded
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: xfs@oss.sgi.com
      Signed-off-by: NJames Morris <jmorris@namei.org>
      82ab8ded
    • D
      CRED: Wrap task credential accesses in the UFS filesystem · a5f773a6
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: Evgeniy Dushistov <dushistov@mail.ru>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      a5f773a6
    • D
      CRED: Wrap task credential accesses in the UDF filesystem · 7706bb39
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Acked-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      7706bb39
    • D
      CRED: Wrap task credential accesses in the UBIFS filesystem · 26bf1946
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: Artem Bityutskiy <dedekind@infradead.org>
      Cc: Adrian Hunter <ext-adrian.hunter@nokia.com>
      Cc: linux-mtd@lists.infradead.org
      Signed-off-by: NJames Morris <jmorris@namei.org>
      26bf1946
    • D
      CRED: Wrap task credential accesses in the SYSV filesystem · fc7333de
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: Christoph Hellwig <hch@infradead.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      fc7333de
    • D
      CRED: Wrap task credential accesses in the SMBFS filesystem · e2950b17
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: Steven French <sfrench@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      e2950b17