1. 14 11月, 2008 13 次提交
    • 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
    • D
      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: 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: 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
    • D
      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 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
  2. 12 11月, 2008 1 次提交
  3. 11 11月, 2008 6 次提交
    • E
      Add a new capable interface that will be used by systems that use audit to · 06112163
      Eric Paris 提交于
      make an A or B type decision instead of a security decision.  Currently
      this is the case at least for filesystems when deciding if a process can use
      the reserved 'root' blocks and for the case of things like the oom
      algorithm determining if processes are root processes and should be less
      likely to be killed.  These types of security system requests should not be
      audited or logged since they are not really security decisions.  It would be
      possible to solve this problem like the vm_enough_memory security check did
      by creating a new LSM interface and moving all of the policy into that
      interface but proves the needlessly bloat the LSM and provide complex
      indirection.
      
      This merely allows those decisions to be made where they belong and to not
      flood logs or printk with denials for thing that are not security decisions.
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Acked-by: NStephen Smalley <sds@tycho.nsa.gov>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      06112163
    • E
      When the capset syscall is used it is not possible for audit to record the · e68b75a0
      Eric Paris 提交于
      actual capbilities being added/removed.  This patch adds a new record type
      which emits the target pid and the eff, inh, and perm cap sets.
      
      example output if you audit capset syscalls would be:
      
      type=SYSCALL msg=audit(1225743140.465:76): arch=c000003e syscall=126 success=yes exit=0 a0=17f2014 a1=17f201c a2=80000000 a3=7fff2ab7f060 items=0 ppid=2160 pid=2223 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts0 ses=1 comm="setcap" exe="/usr/sbin/setcap" subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null)
      type=UNKNOWN[1322] msg=audit(1225743140.465:76): pid=0 cap_pi=ffffffffffffffff cap_pp=ffffffffffffffff cap_pe=ffffffffffffffff
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      e68b75a0
    • E
      Any time fcaps or a setuid app under SECURE_NOROOT is used to result in a · 3fc689e9
      Eric Paris 提交于
      non-zero pE we will crate a new audit record which contains the entire set
      of known information about the executable in question, fP, fI, fE, fversion
      and includes the process's pE, pI, pP.  Before and after the bprm capability
      are applied.  This record type will only be emitted from execve syscalls.
      
      an example of making ping use fcaps instead of setuid:
      
      setcap "cat_net_raw+pe" /bin/ping
      
      type=SYSCALL msg=audit(1225742021.015:236): arch=c000003e syscall=59 success=yes exit=0 a0=1457f30 a1=14606b0 a2=1463940 a3=321b770a70 items=2 ppid=2929 pid=2963 auid=0 uid=500 gid=500 euid=500 suid=500 fsuid=500 egid=500 sgid=500 fsgid=500 tty=pts0 ses=3 comm="ping" exe="/bin/ping" subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null)
      type=UNKNOWN[1321] msg=audit(1225742021.015:236): fver=2 fp=0000000000002000 fi=0000000000000000 fe=1 old_pp=0000000000000000 old_pi=0000000000000000 old_pe=0000000000000000 new_pp=0000000000002000 new_pi=0000000000000000 new_pe=0000000000002000
      type=EXECVE msg=audit(1225742021.015:236): argc=2 a0="ping" a1="127.0.0.1"
      type=CWD msg=audit(1225742021.015:236):  cwd="/home/test"
      type=PATH msg=audit(1225742021.015:236): item=0 name="/bin/ping" inode=49256 dev=fd:00 mode=0100755 ouid=0 ogid=0 rdev=00:00 obj=system_u:object_r:ping_exec_t:s0 cap_fp=0000000000002000 cap_fe=1 cap_fver=2
      type=PATH msg=audit(1225742021.015:236): item=1 name=(null) inode=507915 dev=fd:00 mode=0100755 ouid=0 ogid=0 rdev=00:00 obj=system_u:object_r:ld_so_t:s0
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      3fc689e9
    • E
      This patch will print cap_permitted and cap_inheritable data in the PATH · 851f7ff5
      Eric Paris 提交于
      records of any file that has file capabilities set.  Files which do not
      have fcaps set will not have different PATH records.
      
      An example audit record if you run:
      setcap "cap_net_admin+pie" /bin/bash
      /bin/bash
      
      type=SYSCALL msg=audit(1225741937.363:230): arch=c000003e syscall=59 success=yes exit=0 a0=2119230 a1=210da30 a2=20ee290 a3=8 items=2 ppid=2149 pid=2923 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts0 ses=3 comm="ping" exe="/bin/ping" subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null)
      type=EXECVE msg=audit(1225741937.363:230): argc=2 a0="ping" a1="www.google.com"
      type=CWD msg=audit(1225741937.363:230):  cwd="/root"
      type=PATH msg=audit(1225741937.363:230): item=0 name="/bin/ping" inode=49256 dev=fd:00 mode=0104755 ouid=0 ogid=0 rdev=00:00 obj=system_u:object_r:ping_exec_t:s0 cap_fp=0000000000002000 cap_fi=0000000000002000 cap_fe=1 cap_fver=2
      type=PATH msg=audit(1225741937.363:230): item=1 name=(null) inode=507915 dev=fd:00 mode=0100755 ouid=0 ogid=0 rdev=00:00 obj=system_u:object_r:ld_so_t:s0
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      851f7ff5
    • E
      This patch add a generic cpu endian caps structure and externally available · c0b00441
      Eric Paris 提交于
      functions which retrieve fcaps information from disk.  This information is
      necessary so fcaps information can be collected and recorded by the audit
      system.
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      c0b00441
    • E
      Document the order of arguments for cap_issubset. It's not instantly clear · 9d36be76
      Eric Paris 提交于
      which order the argument should be in.  So give an example.
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      9d36be76
  4. 06 11月, 2008 1 次提交
    • S
      file capabilities: add no_file_caps switch (v4) · 1f29fae2
      Serge E. Hallyn 提交于
      Add a no_file_caps boot option when file capabilities are
      compiled into the kernel (CONFIG_SECURITY_FILE_CAPABILITIES=y).
      
      This allows distributions to ship a kernel with file capabilities
      compiled in, without forcing users to use (and understand and
      trust) them.
      
      When no_file_caps is specified at boot, then when a process executes
      a file, any file capabilities stored with that file will not be
      used in the calculation of the process' new capability sets.
      
      This means that booting with the no_file_caps boot option will
      not be the same as booting a kernel with file capabilities
      compiled out - in particular a task with  CAP_SETPCAP will not
      have any chance of passing capabilities to another task (which
      isn't "really" possible anyway, and which may soon by killed
      altogether by David Howells in any case), and it will instead
      be able to put new capabilities in its pI.  However since fI
      will always be empty and pI is masked with fI, it gains the
      task nothing.
      
      We also support the extra prctl options, setting securebits and
      dropping capabilities from the per-process bounding set.
      
      The other remaining difference is that killpriv, task_setscheduler,
      setioprio, and setnice will continue to be hooked.  That will
      be noticable in the case where a root task changed its uid
      while keeping some caps, and another task owned by the new uid
      tries to change settings for the more privileged task.
      
      Changelog:
      	Nov 05 2008: (v4) trivial port on top of always-start-\
      		with-clear-caps patch
      	Sep 23 2008: nixed file_caps_enabled when file caps are
      		not compiled in as it isn't used.
      		Document no_file_caps in kernel-parameters.txt.
      Signed-off-by: NSerge Hallyn <serue@us.ibm.com>
      Acked-by: NAndrew G. Morgan <morgan@kernel.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      1f29fae2
  5. 04 11月, 2008 2 次提交
  6. 03 11月, 2008 1 次提交
  7. 31 10月, 2008 11 次提交
    • K
      resources: add io-mapping functions to dynamically map large device apertures · 9663f2e6
      Keith Packard 提交于
      Impact: add new generic io_map_*() APIs
      
      Graphics devices have large PCI apertures which would consume a significant
      fraction of a 32-bit address space if mapped during driver initialization.
      Using ioremap at runtime is impractical as it is too slow.
      
      This new set of interfaces uses atomic mappings on 32-bit processors and a
      large static mapping on 64-bit processors to provide reasonable 32-bit
      performance and optimal 64-bit performance.
      
      The current implementation sits atop the io_map_atomic fixmap-based
      mechanism for 32-bit processors.
      
      This includes some editorial suggestions from Randy Dunlap for
      Documentation/io-mapping.txt
      Signed-off-by: NKeith Packard <keithp@keithp.com>
      Signed-off-by: NEric Anholt <eric@anholt.net>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      9663f2e6
    • R
      net: delete excess kernel-doc notation · ad1d967c
      Randy Dunlap 提交于
      Remove excess kernel-doc function parameters from networking header
      & driver files:
      
      Warning(include/net/sock.h:946): Excess function parameter or struct member 'sk' description in 'sk_filter_release'
      Warning(include/linux/netdevice.h:1545): Excess function parameter or struct member 'cpu' description in 'netif_tx_lock'
      Warning(drivers/net/wan/z85230.c:712): Excess function parameter or struct member 'regs' description in 'z8530_interrupt'
      Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      ad1d967c
    • J
      libata: add whitelist for devices with known good pata-sata bridges · 9ce8e307
      Jens Axboe 提交于
      libata currently imposes a UDMA5 max transfer rate and 200 sector max
      transfer size for SATA devices that sit behind a pata-sata bridge. Lots
      of devices have known good bridges that don't need this limit applied.
      The MTRON SSD disks are such devices. Transfer rates are increased by
      20-30% with the restriction removed.
      
      So add a "blacklist" entry for the MTRON devices, with a flag indicating
      that the bridge is known good.
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      9ce8e307
    • T
      gianfar: Fix race in TBI/SerDes configuration · c132419e
      Trent Piepho 提交于
      The init_phy() function attaches to the PHY, then configures the
      SerDes<->TBI link (in SGMII mode).  The TBI is on the MDIO bus with the PHY
      (sort of) and is accessed via the gianfar's MDIO registers, using the
      functions gfar_local_mdio_read/write(), which don't do any locking.
      
      The previously attached PHY will start a work-queue on a timer, and
      probably an irq handler as well, which will talk to the PHY and thus use
      the MDIO bus.  This uses phy_read/write(), which have locking, but not
      against the gfar_local_mdio versions.
      
      The result is that PHY code will try to use the MDIO bus at the same time
      as the SerDes setup code, corrupting the transfers.
      
      Setting up the SerDes before attaching to the PHY will insure that there is
      no race between the SerDes code and *our* PHY, but doesn't fix everything.
      Typically the PHYs for all gianfar devices are on the same MDIO bus, which
      is associated with the first gianfar device.  This means that the first
      gianfar's SerDes code could corrupt the MDIO transfers for a different
      gianfar's PHY.
      
      The lock used by phy_read/write() is contained in the mii_bus structure,
      which is pointed to by the PHY.  This is difficult to access from the
      gianfar drivers, as there is no link between a gianfar device and the
      mii_bus which shares the same MDIO registers.  As far as the device layer
      and drivers are concerned they are two unrelated devices (which happen to
      share registers).
      
      Generally all gianfar devices' PHYs will be on the bus associated with the
      first gianfar.  But this might not be the case, so simply locking the
      gianfar's PHY's mii bus might not lock the mii bus that the SerDes setup
      code is going to use.
      
      We solve this by having the code that creates the gianfar platform device
      look in the device tree for an mdio device that shares the gianfar's
      registers.  If one is found the ID of its platform device is saved in the
      gianfar's platform data.
      
      A new function in the gianfar mii code, gfar_get_miibus(), can use the bus
      ID to search through the platform devices for a gianfar_mdio device with
      the right ID.  The platform device's driver data is the mii_bus structure,
      which the SerDes setup code can use to lock the current bus.
      Signed-off-by: NTrent Piepho <tpiepho@freescale.com>
      CC: Andy Fleming <afleming@freescale.com>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      c132419e
    • F
      spi: fix compile error · effdb949
      Fernando Luis Vazquez Cao 提交于
      Fix compile error below:
      
           LD      drivers/spi/built-in.o
           CC [M]  drivers/spi/spi_gpio.o
         In file included from drivers/spi/spi_gpio.c:26:
         include/linux/spi/spi_bitbang.h:23: error: field `work' has incomplete type
         make[2]: *** [drivers/spi/spi_gpio.o] Error 1
         make[1]: *** [drivers/spi] Error 2
         make: *** [drivers] Error 2
      Signed-off-by: NFernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
      Cc: David Brownell <david-b@pacbell.net>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      effdb949
    • A
      nfsd: fix vm overcommit crash · 731572d3
      Alan Cox 提交于
      Junjiro R.  Okajima reported a problem where knfsd crashes if you are
      using it to export shmemfs objects and run strict overcommit.  In this
      situation the current->mm based modifier to the overcommit goes through a
      NULL pointer.
      
      We could simply check for NULL and skip the modifier but we've caught
      other real bugs in the past from mm being NULL here - cases where we did
      need a valid mm set up (eg the exec bug about a year ago).
      
      To preserve the checks and get the logic we want shuffle the checking
      around and add a new helper to the vm_ security wrappers
      
      Also fix a current->mm reference in nommu that should use the passed mm
      
      [akpm@linux-foundation.org: coding-style fixes]
      [akpm@linux-foundation.org: fix build]
      Reported-by: NJunjiro R. Okajima <hooanon05@yahoo.co.jp>
      Acked-by: NJames Morris <jmorris@namei.org>
      Signed-off-by: NAlan Cox <alan@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      731572d3
    • R
      kernel.h: fix might_sleep kernel-doc · 7106a27b
      Randy Dunlap 提交于
      Put the kernel-doc for might_sleep() _immediately_ before the macro
      (no intervening lines).  Otherwise kernel-doc complains like so:
      
      Warning(linux-2.6.27-rc3-git2//include/linux/kernel.h:129): No description found for parameter 'file'
      Warning(linux-2.6.27-rc3-git2//include/linux/kernel.h:129): No description found for parameter 'line'
      
      because kernel-doc is looking at the wrong function prototype (i.e.,
      __might_sleep).  [Yes, I have a todo note to myself to check/warn for that
      inconsistency in scripts/kernel-doc.]
      Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
      Cc: <Uwe.Kleine-Koenig@digi.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      7106a27b
    • N
      fs: remove prepare_write/commit_write · 4e02ed4b
      Nick Piggin 提交于
      Nothing uses prepare_write or commit_write. Remove them from the tree
      completely.
      
      [akpm@linux-foundation.org: schedule simple_prepare_write() for unexporting]
      Signed-off-by: NNick Piggin <npiggin@suse.de>
      Cc: Christoph Hellwig <hch@lst.de>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      4e02ed4b
    • L
      cgroups: tiny cleanups · 9b913735
      Li Zefan 提交于
      - remove 'private' field from struct subsys
      - remove cgroup_init_smp()
      Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
      Acked-by: NPaul Menage <menage@google.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      9b913735
    • L
      freezer_cg: use thaw_process() in unfreeze_cgroup() · 00c2e63c
      Li Zefan 提交于
      Don't duplicate the implementation of thaw_process().
      
      [akpm@linux-foundation.org: make __thaw_process() static]
      Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
      Cc: Cedric Le Goater <clg@fr.ibm.com>
      Acked-by: NMatt Helsley <matthltc@us.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      00c2e63c
    • K
      mm: increase the default mlock limit from 32k to 64k · 08334222
      Kurt Garloff 提交于
      By default, non-privileged tasks can only mlock() a small amount of
      memory to avoid a DoS attack by ordinary users.  The Linux kernel
      defaulted to 32k (on a 4k page size system) to accommodate the needs of
      gpg.
      
      However, newer gpg2 needs 64k in various circumstances and otherwise
      fails miserably, see bnc#329675.
      
      Change the default to 64k, and make it more agnostic to PAGE_SIZE.
      Signed-off-by: NKurt Garloff <garloff@suse.de>
      Signed-off-by: NNick Piggin <npiggin@suse.de>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      08334222
  8. 30 10月, 2008 1 次提交
  9. 29 10月, 2008 1 次提交
  10. 28 10月, 2008 2 次提交
  11. 27 10月, 2008 1 次提交