25 Aug, 2008

1 commit


25 Jul, 2008

21 commits

  • The ioctls AUTOFS_IOC_TOGGLEREGHOST and AUTOFS_IOC_ASKREGHOST were added
    several years ago but what they were intended for has never been
    implemented (as far as I'm aware noone uses them) so remove them.

    Signed-off-by: Ian Kent
    Reviewed-by: Jeff Moyer
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • This patch re-orgnirzes the checking for and waiting on active expires and
    elininates redundant checks.

    Signed-off-by: Ian Kent
    Cc: Jeff Moyer
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • Appologies, somehow I seem to have sent an out dated version of this
    patch. Here is an additional patch that brings the patch up to date.

    Signed-off-by: Ian Kent
    Cc: Jeff Moyer
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • For direct and offset type mounts that are covered by another mount we
    cannot check the AUTOFS_INF_EXPIRING flag during a path walk which leads
    to lookups walking into an expiring mount while it is being expired.

    For example, for the direct multi-mount map entry with a couple of
    offsets:

    /race/mm1 / :/
    /om1 :/
    /om2 :/

    an autofs trigger mount is mounted on /race/mm1 and when accessed it is
    over mounted and trigger mounts made for /race/mm1/om1 and /race/mm1/om2.
    So it isn't possible for path walks to see the expiring flag at all and
    they happily walk into the file system while it is expiring.

    When expiring these mounts follow_down() must stop at the autofs mount and
    all processes must block in the ->follow_link() method (except the daemon)
    until the expire is complete. This is done by decrementing the d_mounted
    field of the autofs trigger mount root dentry until the expire is
    completed. In ->follow_link() all processes wait on the expire and the
    mount following is completed for the daemon until the expire is complete.

    Signed-off-by: Ian Kent
    Cc: Jeff Moyer
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • The selection of a dentry for expiration and the setting of the
    AUTOFS_INF_EXPIRING flag isn't done atomically which can lead to lookups
    walking into an expiring mount.

    What happens is that an expire is initiated by the daemon and a dentry is
    selected for expire but, since there is no lock held between the selection
    and setting of the expiring flag, a process may find the flag clear and
    continue walking into the mount tree at the same time the daemon attempts
    the expire it.

    Signed-off-by: Ian Kent
    Reviewed-by: Jeff Moyer
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • There are two cases for which a dentry that has a pending mount request
    does not wait for completion. One is via autofs4_revalidate() and the
    other via autofs4_follow_link().

    In revalidate, after the mount point directory is created, but before the
    mount is done, the check in try_to_fill_dentry() can can fail to send the
    dentry to the wait queue since the dentry is positive and the lookup flags
    may contain only LOOKUP_FOLLOW. Although we don't trigger a mount for the
    LOOKUP_FOLLOW flag, if ther's one pending we might as well wait and use
    the mounted dentry for the lookup.

    In autofs4_follow_link() the dentry is not checked to see if it is pending
    so it may fail to call try_to_fill_dentry() and not wait for mount
    completion.

    A dentry that is pending must always be sent to the wait queue.

    Signed-off-by: Ian Kent
    Reviewed-by: Jeff Moyer
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • The mount triggering functionality of readdir and related functions is no
    longer used (and is quite broken as well). The unused portions have been
    removed.

    Signed-off-by: Ian Kent
    Reviewed-by: Jeff Moyer
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • We have been seeing mount requests comming to the automount daemon for
    keys of the form "/" which are lookups for
    invalid map keys. But we can check for this in the kernel module and
    return a fail immediately, without having to send a request to the daemon.

    It is possible to recognise these requests are invalid based on whether
    the request dentry is negative and its relation to the autofs file system
    root.

    For example, given the indirect multi-mount map entry:

    idm1 \
    /mm1 :/
    /mm2 :/

    For a request to mount idm1, IS_ROOT((idm1)->d_parent) will be always be
    true and the dentry may be negative. But directories idm1/mm1 and
    idm1/mm2 will always be created as part of the mount request for idm1. So
    any mount request within idm1 itself must have a positive dentry otherwise
    the map key is invalid.

    In version 4 these multi-mount entries are all mounted and umounted as a
    single request and in version 5 the directories idm1/mm1 and idm1/mm2 are
    created and an autofs fs mounted on them to act as a mount trigger so the
    above is also true.

    This also holds true for the autofs version 4 pseudo direct mount feature.
    When this feature is used without the "--ghost" option automount(8) will
    create internal submounts as we go down the map key paths which are
    essentially normal indirect mounts for which the above holds. If the
    "--ghost" option is given the directories for map keys are created at
    daemon startup so valid map entries correspond to postive dentries in the
    autofs fs.

    autofs version 5 direct mount maps are similar except that the IS_ROOT
    check is not needed. This has been addressed in a previous patch tittled
    "autofs4 - detect invalid direct mount requests".

    For example, given the direct multi-mount map entry:

    /test/dm1 \
    /mm1 :/
    /mm2 :/

    An autofs fs is mounted on /test/dm1 as a trigger mount and when a mount
    is triggered for /test/dm1, the multi-mount offset directories
    /test/dm1/mm1 and /test/dm1/mm2 are created and an autofs fs is mounted on
    them to act as mount triggers. So valid direct mount requests must always
    have a positive dentry if they correspond to a valid map entry.

    Signed-off-by: Ian Kent
    Acked-by: Jeff Moyer
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • autofs v5 direct and offset mounts within an autofs filesystem are
    triggered by existing autofs triger mounts so the mount point dentry must
    be positive. If the mount point dentry is negative then the trigger
    doesn't exist so we can return fail immediately.

    Signed-off-by: Ian Kent
    Cc: Jeff Moyer
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • If an autofs mount becomes catatonic before autofs4_wait_release() is
    called the wait queue counter will not be decremented down to zero and the
    entry will never be freed. There are also races decrementing the wait
    counter in the wait release function. To deal with this the counter needs
    to be updated while holding the wait queue mutex and waiters need to be
    woken up unconditionally when the wait is removed from the queue to ensure
    we eventually free the wait.

    Signed-off-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • It is possible for an autofs mount to become catatonic (and for the daemon
    communication pipe to become NULL) after a wait has been initiallized but
    before the request has been sent to the daemon. We need to check for this
    before sending the request packet.

    Signed-off-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • It see that the patch tittled "autofs4 - fix pending mount race" is
    missing a change that I had recently made.

    It's missing a kfree for the case mutex_lock_interruptible() fails
    to aquire the wait queue mutex.

    Signed-off-by: Ian Kent
    Cc: Jeff Moyer
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • Close a race between a pending mount that is about to finish and a new
    lookup for the same directory.

    Process P1 triggers a mount of directory foo. It sets
    DCACHE_AUTOFS_PENDING in the ->lookup routine, creates a waitq entry for
    'foo', and calls out to the daemon to perform the mount. The autofs
    daemon will then create the directory 'foo', using a new dentry that will
    be hashed in the dcache.

    Before the mount completes, another process, P2, tries to walk into the
    'foo' directory. The vfs path walking code finds an entry for 'foo' and
    calls the revalidate method. Revalidate finds that the entry is not
    PENDING (because PENDING was never set on the dentry created by the
    mkdir), but it does find the directory is empty. Revalidate calls
    try_to_fill_dentry, which sets the PENDING flag and then calls into the
    autofs4 wait code to trigger or wait for a mount of 'foo'. The wait code
    finds the entry for 'foo' and goes to sleep waiting for the completion of
    the mount.

    Yet another process, P3, tries to walk into the 'foo' directory. This
    process again finds a dentry in the dcache for 'foo', and calls into the
    autofs revalidate code.

    The revalidate code finds that the PENDING flag is set, and so calls
    try_to_fill_dentry.

    a) try_to_fill_dentry sets the PENDING flag redundantly for this
    dentry, then calls into the autofs4 wait code.

    b) the autofs4 wait code takes the waitq mutex and searches for an
    entry for 'foo'

    Between a and b, P1 is woken up because the mount completed. P1 takes the
    wait queue mutex, clears the PENDING flag from the dentry, and removes the
    waitqueue entry for 'foo' from the list.

    When it releases the waitq mutex, P3 (eventually) acquires it. At this
    time, it looks for an existing waitq for 'foo', finds none, and so creates
    a new one and calls out to the daemon to mount the 'foo' directory.

    Now, the reason that three processes are required to trigger this race is
    that, because the PENDING flag is not set on the dentry created by mkdir,
    the window for the race would be way to slim for it to ever occur.
    Basically, between the testing of d_mountpoint(dentry) and the taking of
    the waitq mutex, the mount would have to complete and the daemon would
    have to be woken up, and that in turn would have to wake up P1. This is
    simply impossible. Add the third process, though, and it becomes slightly
    more likely.

    Signed-off-by: Jeff Moyer
    Signed-off-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • The autofs4_catatonic_mode() function accesses the wait queue without any
    locking but can be called at any time. This could lead to a possible
    double free of the name field of the wait and a double fput of the daemon
    communication pipe or an fput of a NULL file pointer.

    Signed-off-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • The autofs_wait_queue already contains all of the fields of the
    struct qstr, so change it into a qstr.

    This patch, from Jeff Moyer, has been modified a liitle by myself.

    Signed-off-by: Jeff Moyer
    Signed-off-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Jeff Moyer
     
  • When an open(2) call is made on an autofs mount point directory that
    already exists and the O_DIRECTORY flag is not used the needed mount
    callback to the daemon is not done. This leads to the path walk
    continuing resulting in a callback to the daemon with an incorrect
    key. open(2) is called without O_DIRECTORY by the "find" utility but
    this should be handled properly anyway.

    This happens because autofs needs to use the lookup flags to decide
    when to callback to the daemon to perform a mount to prevent mount
    storms. For example, an autofs indirect mount map that has the "browse"
    option will have the mount point directories are pre-created and the
    stat(2) call made by a color ls against each directory will cause all
    these directories to be mounted. It is unfortunate we need to resort
    to this but mount maps can be quite large. Additionally, if a user
    manually umounts an autofs indirect mount the directory isn't removed
    which also leads to this situation.

    To resolve this autofs needs to use the lookup intent flags to enable
    it to make this decision. This patch adds this check and triggers a
    call back if any of the lookup intent flags are set as all these calls
    warrant a mount attempt be requested.

    I know that external VFS code which uses the lookup flags is something
    that the VFS would like to eliminate but I have no choice as I can't
    see any other way to do this. A VFS dentry or inode operation callback
    which returns the lookup "type" (requires a definition) would be
    sufficient. But this change is needed now and I'm not aware of the form
    that coming VFS changes will take so I'm not willing to propose anything
    along these lines.

    If anyone can provide an alternate method I would be happy to use it.

    [akpm@linux-foundation.org: fix build for concurrent VFS changes]
    Signed-off-by: Ian Kent
    Cc: Al Viro
    Cc: Jeff Moyer
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • Since we now delay hashing of dentrys until the ->mkdir() call, droping
    and re-taking the directory mutex within the ->lookup() function when we
    are being called by user space is not needed. This can lead to a race
    when other processes are attempting to access the same directory during
    mount point directory creation.

    In this case we need to hang onto the mutex to ensure we don't get user
    processes trying to create a mount request for a newly created dentry
    after the mount point entry has already been created. This ensures that
    when we need to check a dentry passed to autofs4_wait(), if it is hashed,
    it is always the mount point dentry and not a new dentry created by
    another lookup during directory creation.

    Signed-off-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • The length of the symlink name has been moved but it needs to be set
    before allocating space for it in the dentry info struct. This corrects a
    mistake in a recent patch.

    Signed-off-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • A while ago a patch to resolve a deadlock during directory creation was
    merged. This delayed the hashing of lookup dentrys until the ->mkdir()
    (or ->symlink()) operation completed to ensure we always went through
    ->lookup() instead of also having processes go through ->revalidate() so
    our VFS locking remained consistent.

    Now we are seeing a couple of side affects of that change in situations
    with heavy mount activity.

    Two cases have been identified:

    1) When a mount request is triggered, due to the delayed hashing, the
    directory created by user space for the mount point doesn't have the
    DCACHE_AUTOFS_PENDING flag set. In the case of an autofs multi-mount
    where a tree of mount point directories are created this can lead to
    the path walk continuing rather than the dentry being sent to the wait
    queue to wait for request completion. This is because, if the pending
    flag isn't set, the criteria for deciding this is a mount in progress
    fails to hold, namely that the dentry is not a mount point and has no
    subdirectories.

    2) A mount request dentry is initially created negative and unhashed.
    It remains this way until the ->mkdir() callback completes. Since it
    is unhashed a fresh dentry is used when the user space mount request
    creates the mount point directory. This leaves the original dentry
    negative and unhashed. But revalidate has no way to tell the VFS that
    the dentry has changed, other than to force another ->lookup() by
    returning false, which is at best wastefull and at worst not possible.
    This results in an -ENOENT return from the original path walk when in
    fact the mount succeeded.

    To resolve this we need to ensure that the same dentry is used in all
    calls to ->lookup() during the course of a mount request. This patch
    achieves that by adding the initial dentry to a look aside list and
    removes it at ->mkdir() or ->symlink() completion (or when the dentry is
    released), since these are the only create operations autofs4 supports.

    Signed-off-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • This patch series enables the use of a single dentry for lookups prior to
    the dentry being hashed and so we no longer need to redo the lookup. This
    patch reverts the patch of commit
    033790449ba9c4dcf8478a87693d33df625c23b5.

    Signed-off-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • Correct the error of making a positive dentry negative after it has been
    instantiated.

    The code that makes this error attempts to re-use the dentry from a
    concurrent expire and mount to resolve a race and the dentry used for the
    lookup must be negative for mounts to trigger in the required cases. The
    fact is that the dentry doesn't need to be re-used because all that is
    needed is to preserve the flag that indicates an expire is still
    incomplete at the time of the mount request.

    This change uses the the dentry to check the flag and wait for the expire
    to complete then discards it instead of attempting to re-use it.

    Signed-off-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     

01 May, 2008

5 commits

  • Here are some more places where path_{get,put}() can be used instead of
    dput()/mntput() pair. Besides that it fixes a bug in autofs4_mount_busy()
    where mntput() was called before dput().

    Signed-off-by: Jan Blunck
    Cc: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Jan Blunck
     
  • Jeff Moyer has identified a case where the autofs4 function
    root.c:try_to_fill_dentry() can return -EBUSY when it should return 0.

    Jeff's description of the way this happens is:

    "automount starts an expire for directory d. after the callout to the daemon,
    but before the rmdir, another process tries to walk into the same directory.
    It puts itself onto the waitq, pending the expiration.

    When the expire finishes, the second process is woken up. In
    try_to_fill_dentry, it does this check:

    status = d_invalidate(dentry);
    if (status != -EBUSY)
    return -EAGAIN;

    And status is EBUSY. The dentry still has a non-zero d_inode, and the
    flags do not contain LOOKUP_CONTINUE or LOOKUP_DIRECTORY

    So, we fall through and return -EBUSY to the caller."

    Signed-off-by: Jeff Moyer
    Signed-off-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Jeff Moyer
     
  • Jeff Moyer has identified a race in due to an execution order dependency
    in the autofs4 function root.c:try_to_fill_dentry().

    Jeff's description of this race is:

    "P1 does a lookup of /mount/submount/foo. Since the VFS can't find an entry
    for "foo" under /mount/submount, it calls into the autofs4 kernel module to
    allocate a new dentry, D1. The kernel creates a new waitq for this lookup and
    calls the daemon to perform the mount.

    The daemon performs a mkdir of the "foo" directory under /mount/submount,
    which ends up creating a *new* dentry, D2.

    Then, P2 does a lookup of /mount/submount/foo. The VFS path walking logic
    finds a dentry in the dcache, D2, and calls the revalidate function with this.
    In the autofs4 revalidate code, we then trigger a mount, since the dentry is
    an empty directory that isn't a mountpoint, and so set DCACHE_AUTOFS_PENDING
    and call into the wait code to trigger the mount.

    The wait code finds our existing waitq entry (since it is keyed off of the
    directory name) and adds itself to the list of waiters.

    After the daemon finishes the mount, it calls back into the kernel to release
    the waiters. When this happens, P1 is woken up and goes about clearing the
    DCACHE_AUTOFS_PENDING flag, but it does this in D1! So, given that P1 in our
    case is a program that will immediately try to access a file under
    /mount/submount/foo, we end up finding the dentry D2 which still has the
    pending flag set, and we set out to wait for a mount *again*!

    So, one way to address this is to re-do the lookup at the end of
    try_to_fill_dentry, and to clear the pending flag on the hashed dentry. This
    seems a sane approach to me."

    And Jeff's patch does this.

    Signed-off-by: Jeff Moyer
    Signed-off-by-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Jeff Moyer
     
  • Catch invalid dentry when calculating its path.

    Signed-off-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     
  • Re-order some code in expire.c:autofs4_expire_indirect() to avoid compile
    warning, reported by Harvey Harrison:

    CHECK fs/autofs4/expire.c
    fs/autofs4/expire.c:383:2: warning: context imbalance in
    'autofs4_expire_indirect' - unexpected unlock

    Signed-off-by: Ian Kent
    Reviewed-by: Harvey Harrison
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     

30 Apr, 2008

1 commit


29 Apr, 2008

1 commit

  • fs/autofs4/root.c:536:23: warning: symbol 'ino' shadows an earlier one
    fs/autofs4/root.c:510:22: originally declared here

    There is no need to redeclare, we are at the end of the loop and in
    the next iteration of the loop, ino will be reset.

    Signed-off-by: Harvey Harrison
    Acked-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Harvey Harrison
     

15 Feb, 2008

2 commits

  • * Add path_put() functions for releasing a reference to the dentry and
    vfsmount of a struct path in the right order

    * Switch from path_release(nd) to path_put(&nd->path)

    * Rename dput_path() to path_put_conditional()

    [akpm@linux-foundation.org: fix cifs]
    Signed-off-by: Jan Blunck
    Signed-off-by: Andreas Gruenbacher
    Acked-by: Christoph Hellwig
    Cc:
    Cc: Al Viro
    Cc: Steven French
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Jan Blunck
     
  • This is the central patch of a cleanup series. In most cases there is no good
    reason why someone would want to use a dentry for itself. This series reflects
    that fact and embeds a struct path into nameidata.

    Together with the other patches of this series
    - it enforced the correct order of getting/releasing the reference count on
    pairs
    - it prepares the VFS for stacking support since it is essential to have a
    struct path in every place where the stack can be traversed
    - it reduces the overall code size:

    without patch series:
    text data bss dec hex filename
    5321639 858418 715768 6895825 6938d1 vmlinux

    with patch series:
    text data bss dec hex filename
    5320026 858418 715768 6894212 693284 vmlinux

    This patch:

    Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere.

    [akpm@linux-foundation.org: coding-style fixes]
    [akpm@linux-foundation.org: fix cifs]
    [akpm@linux-foundation.org: fix smack]
    Signed-off-by: Jan Blunck
    Signed-off-by: Andreas Gruenbacher
    Acked-by: Christoph Hellwig
    Cc: Al Viro
    Cc: Casey Schaufler
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Jan Blunck
     

09 Feb, 2008

1 commit


20 Oct, 2007

1 commit

  • The set of functions process_session, task_session, process_group and
    task_pgrp is confusing, as the names can be mixed with each other when looking
    at the code for a long time.

    The proposals are to
    * equip the functions that return the integer with _nr suffix to
    represent that fact,
    * and to make all functions work with task (not process) by making
    the common prefix of the same name.

    For monotony the routines signal_session() and set_signal_session() are
    replaced with task_session_nr() and set_task_session(), especially since they
    are only used with the explicit task->signal dereference.

    Signed-off-by: Pavel Emelianov
    Acked-by: Serge E. Hallyn
    Cc: Kirill Korotaev
    Cc: "Eric W. Biederman"
    Cc: Cedric Le Goater
    Cc: Herbert Poetzl
    Cc: Sukadev Bhattiprolu
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Pavel Emelianov
     

19 Oct, 2007

1 commit

  • Get rid of sparse related warnings from places that use integer as NULL
    pointer.

    [akpm@linux-foundation.org: coding-style fixes]
    Signed-off-by: Stephen Hemminger
    Cc: Andi Kleen
    Cc: Jeff Garzik
    Cc: Matt Mackall
    Cc: Ian Kent
    Cc: Arnd Bergmann
    Cc: Davide Libenzi
    Cc: Stephen Smalley
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Stephen Hemminger
     

17 Oct, 2007

1 commit


23 Aug, 2007

1 commit

  • Due to inconsistent locking in the VFS between calls to lookup and
    revalidate deadlock can occur in the automounter.

    The inconsistency is that the directory inode mutex is held for both lookup
    and revalidate calls when called via lookup_hash whereas it is held only
    for lookup during a path walk. Consequently, if the mutex is held during a
    call to revalidate autofs4 can't release the mutex to callback the daemon
    as it can't know whether it owns the mutex.

    This situation happens when a process tries to create a directory within an
    automount and a second process also tries to create the same directory
    between the lookup and the mkdir. Since the first process has dropped the
    mutex for the daemon callback, the second process takes it during
    revalidate leading to deadlock between the autofs daemon and the second
    process when the daemon tries to create the mount point directory.

    After spending quite a bit of time trying to resolve this on more than one
    occassion, using rather complex and ulgy approaches, it turns out that just
    delaying the hashing of the dentry until the create operation works fine.

    Signed-off-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent
     

11 May, 2007

1 commit

  • Fix coding style errors (extra spaces, long lines) in autofs and autofs4 files
    being modified for container/pidspace issues.

    Signed-off-by: Sukadev Bhattiprolu
    Cc: Cedric Le Goater
    Cc: Dave Hansen
    Cc: Serge Hallyn
    Cc:
    Cc: Eric W. Biederman
    Cc: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Sukadev Bhattiprolu
     

09 May, 2007

1 commit


13 Apr, 2007

1 commit

  • Commit f50b6f8691cae2e0064c499dd3ef3f31142987f0 introduced a race in
    autofs4 between autofs_lookup_unhashed() and autofs_dentry_release().

    autofs_dentry_release() ends up clearing the ->dentry and ->inode members
    of autofs_info before removing it from the rehash list. The list is
    protected by the rehash lock in both functions, but since
    autofs_dentry_release() starts tearing the autofs_info struct down before
    removing it from the list, autofs_lookup_unhashed() can get a autofs_info
    with a NULL dentry.

    This patch moves the clearing of ->dentry and ->inode after the removal
    from the rehash list.

    Signed-off-by: Jeff Mahoney
    Acked-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Jeff Mahoney
     

21 Feb, 2007

1 commit

  • This problem was identified and fixed some time ago by Jeff Moyer but it fell
    through the cracks somehow.

    It is possible that a user space application could remove and re-create a
    directory during a request. To avoid returning a failure from lookup
    incorrectly when our current dentry is unhashed we need to check if another
    positive, hashed dentry matching this one exists and if so return it instead
    of a fail.

    Signed-off-by: Jeff Moyer
    Signed-off-by: Ian Kent
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ian Kent