18 Jan, 2009

1 commit


14 Jan, 2009

2 commits


01 Jan, 2009

1 commit

  • Fix the following sparse warning:

    CC security/keys/key.o
    security/keys/keyctl.c:1297:10: warning: incorrect type in argument 2 (different address spaces)
    security/keys/keyctl.c:1297:10: expected char [noderef] *buffer
    security/keys/keyctl.c:1297:10: got char *

    which appears to be caused by lack of __user annotation to the cast of
    a syscall argument.

    Signed-off-by: James Morris
    Acked-by: David Howells

    James Morris
     

29 Dec, 2008

1 commit

  • Fix variable uninitialisation warnings introduced in:

    commit 8bbf4976b59fc9fc2861e79cab7beb3f6d647640
    Author: David Howells
    Date: Fri Nov 14 10:39:14 2008 +1100

    KEYS: Alter use of key instantiation link-to-keyring argument

    As:

    security/keys/keyctl.c: In function 'keyctl_negate_key':
    security/keys/keyctl.c:976: warning: 'dest_keyring' may be used uninitialized in this function
    security/keys/keyctl.c: In function 'keyctl_instantiate_key':
    security/keys/keyctl.c:898: warning: 'dest_keyring' may be used uninitialized in this function

    Some versions of gcc notice that get_instantiation_key() doesn't always set
    *_dest_keyring, but fail to observe that if this happens then *_dest_keyring
    will not be read by the caller.

    Reported-by: Linus Torvalds
    Signed-off-by: David Howells
    Signed-off-by: James Morris

    David Howells
     

14 Nov, 2008

9 commits

  • 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: David Howells
    Acked-by: James Morris
    Acked-by: Serge Hallyn
    Signed-off-by: James Morris

    David Howells
     
  • 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: David Howells
    Acked-by: James Morris
    Signed-off-by: James Morris

    David Howells
     
  • Separate per-task-group keyrings from signal_struct and dangle their anchor
    from the cred struct rather than the signal_struct.

    Signed-off-by: David Howells
    Reviewed-by: James Morris
    Signed-off-by: James Morris

    David Howells
     
  • 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: David Howells
    Acked-by: James Morris
    Acked-by: Serge Hallyn
    Signed-off-by: James Morris

    David Howells
     
  • Wrap current->cred and a few other accessors to hide their actual
    implementation.

    Signed-off-by: David Howells
    Acked-by: James Morris
    Acked-by: Serge Hallyn
    Signed-off-by: James Morris

    David Howells
     
  • 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

    Signed-off-by: David Howells
    Acked-by: James Morris
    Acked-by: Serge Hallyn
    Signed-off-by: James Morris

    David Howells
     
  • 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 | 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: David Howells
    Reviewed-by: James Morris
    Signed-off-by: James Morris

    David Howells
     
  • Disperse the bits of linux/key_ui.h as the reason they were put here (keyfs)
    didn't get in.

    Signed-off-by: David Howells
    Reviewed-by: James Morris
    Signed-off-by: James Morris

    David Howells
     
  • 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: David Howells
    Reviewed-by: James Morris
    Acked-by: Serge Hallyn
    Signed-off-by: James Morris

    David Howells
     

07 Jun, 2008

1 commit


29 Apr, 2008

9 commits

  • Since these two source files invoke kmalloc(), they should explicitly
    include .

    Signed-off-by: Robert P. J. Day
    Cc: David Howells
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Robert P. J. Day
     
  • Make the keyring quotas controllable through /proc/sys files:

    (*) /proc/sys/kernel/keys/root_maxkeys
    /proc/sys/kernel/keys/root_maxbytes

    Maximum number of keys that root may have and the maximum total number of
    bytes of data that root may have stored in those keys.

    (*) /proc/sys/kernel/keys/maxkeys
    /proc/sys/kernel/keys/maxbytes

    Maximum number of keys that each non-root user may have and the maximum
    total number of bytes of data that each of those users may have stored in
    their keys.

    Also increase the quotas as a number of people have been complaining that it's
    not big enough. I'm not sure that it's big enough now either, but on the
    other hand, it can now be set in /etc/sysctl.conf.

    Signed-off-by: David Howells
    Cc:
    Cc:
    Cc:
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    David Howells
     
  • Don't generate the per-UID user and user session keyrings unless they're
    explicitly accessed. This solves a problem during a login process whereby
    set*uid() is called before the SELinux PAM module, resulting in the per-UID
    keyrings having the wrong security labels.

    This also cures the problem of multiple per-UID keyrings sometimes appearing
    due to PAM modules (including pam_keyinit) setuiding and causing user_structs
    to come into and go out of existence whilst the session keyring pins the user
    keyring. This is achieved by first searching for extant per-UID keyrings
    before inventing new ones.

    The serial bound argument is also dropped from find_keyring_by_name() as it's
    not currently made use of (setting it to 0 disables the feature).

    Signed-off-by: David Howells
    Cc:
    Cc:
    Cc:
    Cc: Stephen Smalley
    Cc: James Morris
    Cc: Chris Wright
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    David Howells
     
  • The key_create_or_update() function provided by the keyring code has a default
    set of permissions that are always applied to the key when created. This
    might not be desirable to all clients.

    Here's a patch that adds a "perm" parameter to the function to address this,
    which can be set to KEY_PERM_UNDEF to revert to the current behaviour.

    Signed-off-by: Arun Raghavan
    Signed-off-by: David Howells
    Cc: Satyam Sharma
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Arun Raghavan
     
  • Signed-off-by: Alexey Dobriyan
    Cc: David Howells
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Alexey Dobriyan
     
  • Add a keyctl() function to get the security label of a key.

    The following is added to Documentation/keys.txt:

    (*) Get the LSM security context attached to a key.

    long keyctl(KEYCTL_GET_SECURITY, key_serial_t key, char *buffer,
    size_t buflen)

    This function returns a string that represents the LSM security context
    attached to a key in the buffer provided.

    Unless there's an error, it always returns the amount of data it could
    produce, even if that's too big for the buffer, but it won't copy more
    than requested to userspace. If the buffer pointer is NULL then no copy
    will take place.

    A NUL character is included at the end of the string if the buffer is
    sufficiently big. This is included in the returned count. If no LSM is
    in force then an empty string will be returned.

    A process must have view permission on the key for this function to be
    successful.

    [akpm@linux-foundation.org: declare keyctl_get_security()]
    Signed-off-by: David Howells
    Acked-by: Stephen Smalley
    Cc: Paul Moore
    Cc: Chris Wright
    Cc: James Morris
    Cc: Kevin Coffman
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    David Howells
     
  • Allow the callout data to be passed as a blob rather than a string for
    internal kernel services that call any request_key_*() interface other than
    request_key(). request_key() itself still takes a NUL-terminated string.

    The functions that change are:

    request_key_with_auxdata()
    request_key_async()
    request_key_async_with_auxdata()

    Signed-off-by: David Howells
    Cc: Paul Moore
    Cc: Chris Wright
    Cc: Stephen Smalley
    Cc: James Morris
    Cc: Kevin Coffman
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    David Howells
     
  • Check the starting keyring as part of the search to (a) see if that is what
    we're searching for, and (b) to check it is still valid for searching.

    The scenario: User in process A does things that cause things to be created in
    its process session keyring. The user then does an su to another user and
    starts a new process, B. The two processes now share the same process session
    keyring.

    Process B does an NFS access which results in an upcall to gssd. When gssd
    attempts to instantiate the context key (to be linked into the process session
    keyring), it is denied access even though it has an authorization key.

    The order of calls is:

    keyctl_instantiate_key()
    lookup_user_key() (the default: case)
    search_process_keyrings(current)
    search_process_keyrings(rka->context) (recursive call)
    keyring_search_aux()

    keyring_search_aux() verifies the keys and keyrings underneath the top-level
    keyring it is given, but that top-level keyring is neither fully validated nor
    checked to see if it is the thing being searched for.

    This patch changes keyring_search_aux() to:
    1) do more validation on the top keyring it is given and
    2) check whether that top-level keyring is the thing being searched for

    Signed-off-by: Kevin Coffman
    Signed-off-by: David Howells
    Cc: Paul Moore
    Cc: Chris Wright
    Cc: Stephen Smalley
    Cc: James Morris
    Cc: Kevin Coffman
    Cc: Trond Myklebust
    Cc: "J. Bruce Fields"
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Kevin Coffman
     
  • Increase the size of a payload that can be used to instantiate a key in
    add_key() and keyctl_instantiate_key(). This permits huge CIFS SPNEGO blobs
    to be passed around. The limit is raised to 1MB. If kmalloc() can't allocate
    a buffer of sufficient size, vmalloc() will be tried instead.

    Signed-off-by: David Howells
    Cc: Paul Moore
    Cc: Chris Wright
    Cc: Stephen Smalley
    Cc: James Morris
    Cc: Kevin Coffman
    Cc: Steven French
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    David Howells
     

18 Apr, 2008

1 commit


08 Feb, 2008

1 commit


25 Jan, 2008

1 commit


17 Oct, 2007

1 commit

  • Make request_key() and co fundamentally asynchronous to make it easier for
    NFS to make use of them. There are now accessor functions that do
    asynchronous constructions, a wait function to wait for construction to
    complete, and a completion function for the key type to indicate completion
    of construction.

    Note that the construction queue is now gone. Instead, keys under
    construction are linked in to the appropriate keyring in advance, and that
    anyone encountering one must wait for it to be complete before they can use
    it. This is done automatically for userspace.

    The following auxiliary changes are also made:

    (1) Key type implementation stuff is split from linux/key.h into
    linux/key-type.h.

    (2) AF_RXRPC provides a way to allocate null rxrpc-type keys so that AFS does
    not need to call key_instantiate_and_link() directly.

    (3) Adjust the debugging macros so that they're -Wformat checked even if
    they are disabled, and make it so they can be enabled simply by defining
    __KDEBUG to be consistent with other code of mine.

    (3) Documentation.

    [alan@lxorguk.ukuu.org.uk: keys: missing word in documentation]
    Signed-off-by: David Howells
    Signed-off-by: Alan Cox
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    David Howells
     

20 Jul, 2007

1 commit

  • Slab destructors were no longer supported after Christoph's
    c59def9f222d44bb7e2f0a559f2906191a0862d7 change. They've been
    BUGs for both slab and slub, and slob never supported them
    either.

    This rips out support for the dtor pointer from kmem_cache_create()
    completely and fixes up every single callsite in the kernel (there were
    about 224, not including the slab allocator definitions themselves,
    or the documentation references).

    Signed-off-by: Paul Mundt

    Paul Mundt
     

18 Jul, 2007

1 commit

  • Rather than using a tri-state integer for the wait flag in
    call_usermodehelper_exec, define a proper enum, and use that. I've
    preserved the integer values so that any callers I've missed should
    still work OK.

    Signed-off-by: Jeremy Fitzhardinge
    Cc: James Bottomley
    Cc: Randy Dunlap
    Cc: Christoph Hellwig
    Cc: Andi Kleen
    Cc: Paul Mackerras
    Cc: Johannes Berg
    Cc: Ralf Baechle
    Cc: Bjorn Helgaas
    Cc: Joel Becker
    Cc: Tony Luck
    Cc: Kay Sievers
    Cc: Srivatsa Vaddagiri
    Cc: Oleg Nesterov
    Cc: David Howells

    Jeremy Fitzhardinge
     

27 Apr, 2007

1 commit

  • Export the keyring key type definition and document its availability.

    Add alternative types into the key's type_data union to make it more useful.
    Not all users necessarily want to use it as a list_head (AF_RXRPC doesn't, for
    example), so make it clear that it can be used in other ways.

    Signed-off-by: David Howells
    Signed-off-by: David S. Miller

    David Howells
     

15 Feb, 2007

1 commit

  • After Al Viro (finally) succeeded in removing the sched.h #include in module.h
    recently, it makes sense again to remove other superfluous sched.h includes.
    There are quite a lot of files which include it but don't actually need
    anything defined in there. Presumably these includes were once needed for
    macros that used to live in sched.h, but moved to other header files in the
    course of cleaning it up.

    To ease the pain, this time I did not fiddle with any header files and only
    removed #includes from .c-files, which tend to cause less trouble.

    Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
    arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
    allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
    configs in arch/arm/configs on arm. I also checked that no new warnings were
    introduced by the patch (actually, some warnings are removed that were emitted
    by unnecessarily included header files).

    Signed-off-by: Tim Schmielau
    Acked-by: Russell King
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Tim Schmielau
     

13 Feb, 2007

1 commit

  • Many struct file_operations in the kernel can be "const". Marking them const
    moves these to the .rodata section, which avoids false sharing with potential
    dirty data. In addition it'll catch accidental writes at compile time to
    these shared resources.

    Signed-off-by: Arjan van de Ven
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Arjan van de Ven
     

07 Feb, 2007

1 commit

  • Fix the key serial number collision avoidance code in key_alloc_serial().

    This didn't use to be so much of a problem as the key serial numbers were
    allocated from a simple incremental counter, and it would have to go through
    two billion keys before it could possibly encounter a collision. However, now
    that random numbers are used instead, collisions are much more likely.

    This is fixed by finding a hole in the rbtree where the next unused serial
    number ought to be and using that by going almost back to the top of the
    insertion routine and redoing the insertion with the new serial number rather
    than trying to be clever and attempting to work out the insertion point
    pointer directly.

    This fixes kernel BZ #7727.

    Signed-off-by: David Howells
    Signed-off-by: Linus Torvalds

    David Howells
     

08 Dec, 2006

4 commits


22 Nov, 2006

1 commit

  • Pass the work_struct pointer to the work function rather than context data.
    The work function can use container_of() to work out the data.

    For the cases where the container of the work_struct may go away the moment the
    pending bit is cleared, it is made possible to defer the release of the
    structure by deferring the clearing of the pending bit.

    To make this work, an extra flag is introduced into the management side of the
    work_struct. This governs auto-release of the structure upon execution.

    Ordinarily, the work queue executor would release the work_struct for further
    scheduling or deallocation by clearing the pending bit prior to jumping to the
    work function. This means that, unless the driver makes some guarantee itself
    that the work_struct won't go away, the work function may not access anything
    else in the work_struct or its container lest they be deallocated.. This is a
    problem if the auxiliary data is taken away (as done by the last patch).

    However, if the pending bit is *not* cleared before jumping to the work
    function, then the work function *may* access the work_struct and its container
    with no problems. But then the work function must itself release the
    work_struct by calling work_release().

    In most cases, automatic release is fine, so this is the default. Special
    initiators exist for the non-auto-release case (ending in _NAR).

    Signed-Off-By: David Howells

    David Howells
     

30 Jun, 2006

1 commit

  • The proposed NFS key type uses its own method of passing key requests to
    userspace (upcalling) rather than invoking /sbin/request-key. This is
    because the responsible userspace daemon should already be running and will
    be contacted through rpc_pipefs.

    This patch permits the NFS filesystem to pass auxiliary data to the upcall
    operation (struct key_type::request_key) so that the upcaller can use a
    pre-existing communications channel more easily.

    Signed-off-by: David Howells
    Acked-By: Kevin Coffman
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    David Howells