Commit Graph

68 Commits

Author SHA1 Message Date
jh
309885e54e - Assert that dm_lock is exclusively held in devfs_rules_apply() and
in devfs_vmkdir() while adding the entry to de_list of the parent.
- Apply devfs rules to newly created directories and symbolic links.

PR:		kern/125034
Submitted by:	Mateusz Guzik (original version)
2010-12-15 16:42:44 +00:00
jh
400a76c2ba Add a new function devfs_dev_exists() to be able to find out if a
specific devfs path already exists.

The function will be used from kern_conf.c to detect duplicate device
registrations. Callers must hold the devmtx mutex.

Reviewed by:	kib
2010-09-27 18:20:56 +00:00
jh
b6e78e30f2 Add reference counting for devfs paths containing user created symbolic
links. The reference counting is needed to be able to determine if a
specific devfs path exists. For true device file paths we can traverse
the cdevp_list but a separate directory list is needed for user created
symbolic links.

Add a new directory entry flag DE_USER to mark entries which should
unreference their parent directory on deletion.

A new function to traverse cdevp_list and the directory list will be
introduced in a separate commit.

Idea from:	kib
Reviewed by:	kib
2010-09-27 17:47:09 +00:00
jh
8c48e7bab1 - For consistency, remove "." and ".." entries from de_dlist before
calling devfs_delete() (and thus possibly dropping dm_lock) in
  devfs_rmdir_empty().
- Assert that we don't return doomed entries from devfs_find(). [1]

Suggested by:	kib [1]
Reviewed by:	kib
2010-09-18 18:37:41 +00:00
jh
02ebb2e3c3 Remove empty devfs directories automatically.
devfs_delete() now recursively removes empty parent directories unless
the DEVFS_DEL_NORECURSE flag is specified. devfs_delete() can't be
called anymore with a parent directory vnode lock held because the
possible parent directory deletion needs to lock the vnode. Thus we
unlock the parent directory vnode in devfs_remove() before calling
devfs_delete().

Call devfs_populate_vp() from devfs_symlink() and devfs_vptocnp() as now
directories can get removed.

Add a check for DE_DOOMED flag to devfs_populate_vp() because
devfs_delete() drops dm_lock before the VI_DOOMED vnode flag gets set.
This ensures that devfs_populate_vp() returns an error for directories
which are in progress of deletion.

Reviewed by:	kib
Discussed on:	freebsd-current (mostly silence)
2010-09-15 14:23:55 +00:00
jh
2e34ad384b Allow user created symbolic links to cover device files and directories
if the device file appears during or after the link creation.

User created symbolic links are now inserted at the head of the
directory entry list after the "." and ".." entries. A new directory
entry flag DE_COVERED indicates that an entry is covered by a symbolic
link.

PR:		kern/114057
Reviewed by:	kib
Idea from:	kib
Discussed on:	freebsd-current (mostly silence)
2010-08-12 15:29:07 +00:00
jh
bc3fa141fa Add a new function devfs_parent_dirent() for resolving devfs parent
directory entry. Use the new function in devfs_fqpn(), devfs_lookupx()
and devfs_vptocnp() instead of manually resolving the parent entry.

Reviewed by:	kib
2010-06-09 15:29:12 +00:00
kib
77dcee6926 Add MAKEDEV_NOWAIT flag to make_dev_credf(9), to create a device node
in a no-sleep context. If resource allocation cannot be done without
sleep, make_dev_credf() fails and returns NULL.

Reviewed by:	jh
MFC after:	2 weeks
2010-05-06 19:22:50 +00:00
jh
0cfb62fa2a Revert r206560. The change doesn't work correctly in all cases with
multiple devfs mounts.
2010-04-16 07:02:28 +00:00
jh
7013f95fb6 - Ignore and report duplicate and empty device names in devfs_populate_loop()
instead of causing erratic behavior. Currently make_dev(9) can't fail, so
  there is no way to report an error to make_dev(9) callers.
- Disallow using "." and ".." in device path names. It didn't work previously
  but now it is reported rather than panicing.
- Treat multiple sequential slashes as single in device path names.

Discussed with:	pjd
2010-04-13 18:53:39 +00:00
ed
39978ea638 Properly use dev_refl()/dev_rel() in kern.devname.
While there, perform some clean-up fixes. Update some stale comments on
struct cdev * instead of dev_t and devfs_random(). Also add some missing
whitespace.

MFC after:	1 week
2010-01-31 15:19:16 +00:00
rwatson
f4934662e5 Move "options MAC" from opt_mac.h to opt_global.h, as it's now in GENERIC
and used in a large number of files, but also because an increasing number
of incorrect uses of MAC calls were sneaking in due to copy-and-paste of
MAC-aware code without the associated opt_mac.h include.

Discussed with:	pjd
2009-06-05 14:55:22 +00:00
ed
50efccc9f0 Mark most often used sysctl's as MPSAFE.
After running a `make buildkernel', I noticed most of the Giant locks in
sysctl are only caused by a very small amount of sysctl's:

- sysctl.name2oid. This one is locked by SYSCTL_LOCK, just like
  sysctl.oidfmt.

- kern.ident, kern.osrelease, kern.version, etc. These are just constant
  strings.

- kern.arandom, used by the stack protector. It is already protected by
  arc4_mtx.

I also saw the following sysctl's show up. Not as often as the ones
above, but still quite often:

- security.jail.jailed. Also mark security.jail.list as MPSAFE. They
  don't need locking or already use allprison_lock.

- kern.devname, used by devname(3), ttyname(3), etc.

This seems to reduce Giant locking inside sysctl by ~75% in my primitive
test setup.
2009-01-28 19:58:05 +00:00
ed
b03d0693f2 Already initialize the vfs timestamps inside the cdev upon allocation.
In the MPSAFE TTY branch I noticed the vfs timestamps inside devfs were
allocated with 0, where the getattr() routine bumps the timestamps to
boottime if the value is below 3600. The reason why it has been designed
like this, is because timestamps during boot are likely to be invalid.

This means that device nodes that are created on demand (posix_openpt())
have timestamps with a value of boottime, which is not what we want.
Solve this by calling vfs_timestamp() inside devfs_alloc().

Discussed with:	kib
2008-09-21 14:02:43 +00:00
kib
eecc60305f Struct cdev is always the member of the struct cdev_priv. When devfs
needed to promote cdev to cdev_priv, the si_priv pointer was followed.

Use member2struct() to calculate address of the wrapping cdev_priv.
Rename si_priv to __si_reserved.

Tested by:	pho
Reviewed by:	ed
MFC after:	2 weeks
2008-06-16 17:34:59 +00:00
attilio
71b7824213 VOP_LOCK1() (and so VOP_LOCK()) and VOP_UNLOCK() are only used in
conjuction with 'thread' argument passing which is always curthread.
Remove the unuseful extra-argument and pass explicitly curthread to lower
layer functions, when necessary.

KPI results broken by this change, which should affect several ports, so
version bumping and manpage update will be further committed.

Tested by: kris, pho, Diego Sardina <siarodx at gmail dot com>
2008-01-13 14:44:15 +00:00
attilio
18d0a0dd51 vn_lock() is currently only used with the 'curthread' passed as argument.
Remove this argument and pass curthread directly to underlying
VOP_LOCK1() VFS method. This modify makes the code cleaner and in
particular remove an annoying dependence helping next lockmgr() cleanup.
KPI results, obviously, changed.

Manpage and FreeBSD_version will be updated through further commits.

As a side note, would be valuable to say that next commits will address
a similar cleanup about VFS methods, in particular vop_lock1 and
vop_unlock.

Tested by:	Diego Sardina <siarodx at gmail dot com>,
		Andrea Di Pasquale <whyx dot it at gmail dot com>
2008-01-10 01:10:58 +00:00
rwatson
60570a92bf Merge first in a series of TrustedBSD MAC Framework KPI changes
from Mac OS X Leopard--rationalize naming for entry points to
the following general forms:

  mac_<object>_<method/action>
  mac_<object>_check_<method/action>

The previous naming scheme was inconsistent and mostly
reversed from the new scheme.  Also, make object types more
consistent and remove spaces from object types that contain
multiple parts ("posix_sem" -> "posixsem") to make mechanical
parsing easier.  Introduce a new "netinet" object type for
certain IPv4/IPv6-related methods.  Also simplify, slightly,
some entry point names.

All MAC policy modules will need to be recompiled, and modules
not updates as part of this commit will need to be modified to
conform to the new KPI.

Sponsored by:	SPARTA (original patches against Mac OS X)
Obtained from:	TrustedBSD Project, Apple Computer
2007-10-24 19:04:04 +00:00
rwatson
62d2d15116 Rename mac*devfsdirent*() to mac*devfs*() to synchronize with SEDarwin,
where similar data structures exist to support devfs and the MAC
Framework, but are named differently.

Obtained from:	TrustedBSD Project
Sponsored by:	SPARTA, Inc.
2007-04-23 13:36:54 +00:00
rwatson
7beaaf5cd2 Complete break-out of sys/sys/mac.h into sys/security/mac/mac_framework.h
begun with a repo-copy of mac.h to mac_framework.h.  sys/mac.h now
contains the userspace and user<->kernel API and definitions, with all
in-kernel interfaces moved to mac_framework.h, which is now included
across most of the kernel instead.

This change is the first step in a larger cleanup and sweep of MAC
Framework interfaces in the kernel, and will not be MFC'd.

Obtained from:	TrustedBSD Project
Sponsored by:	SPARTA
2006-10-22 11:52:19 +00:00
kib
afa2e43fb6 Properly lock the vnode around vgone() calls.
Unlock the vnode in devfs_close() while calling into the driver d_close()
routine.

devfs_revoke() changes by:	ups
Reviewed and bugfixes by:	tegge
Tested by:	mbr, Peter Holm
Approved by:	pjd (mentor)
MFC after:	1 week
2006-10-18 11:17:14 +00:00
kib
ecf34f4504 Resolve the devfs deadlock caused by LOR between devfs_mount->dm_lock and
vnode lock in devfs_allocv. Do this by temporary dropping dm_lock around
vnode locking.

For safe operation, add hold counters for both devfs_mount and devfs_dirent,
and DE_DOOMED flag for devfs_dirent. The facilities allow to continue after
dropping of the dm_lock, by making sure that referenced memory does not
disappear.

Reviewed by:	tegge
Tested by:	kris
Approved by:	kan (mentor)
PR:		kern/102335
2006-09-18 13:23:08 +00:00
phk
0f924547b0 Remove the NDEVFSINO and NDEVFSOVERFLOW options which no longer exists in
DEVFS.

Remove the opt_devfs.h file now that it is empty.
2006-07-17 09:07:02 +00:00
jeff
4c3ad6634a - We must hold a reference to a vnode before calling vgone() otherwise
it may not be removed from the freelist.

MFC After:	1 week
Found by:	kris
2006-02-22 09:05:40 +00:00
phk
6a408cbd71 Rewamp DEVFS internals pretty severely [1].
Give DEVFS a proper inode called struct cdev_priv.  It is important
to keep in mind that this "inode" is shared between all DEVFS
mountpoints, therefore it is protected by the global device mutex.

Link the cdev_priv's into a list, protected by the global device
mutex.  Keep track of each cdev_priv's state with a flag bit and
of references from mountpoints with a dedicated usecount.

Reap the benefits of much improved kernel memory allocator and the
generally better defined device driver APIs to get rid of the tables
of pointers + serial numbers, their overflow tables,  the atomics
to muck about in them and all the trouble that resulted in.

This makes RAM the only limit on how many devices we can have.

The cdev_priv is actually a super struct containing the normal cdev
as the "public" part, and therefore allocation and freeing has moved
to devfs_devs.c from kern_conf.c.

The overall responsibility is (to be) split such that kern/kern_conf.c
is the stuff that deals with drivers and struct cdev and fs/devfs
handles filesystems and struct cdev_priv and their private liason
exposed only in devfs_int.h.

Move the inode number from cdev to cdev_priv and allocate inode
numbers properly with unr.  Local dirents in the mountpoints
(directories, symlinks) allocate inodes from the same pool to
guarantee against overlaps.

Various other fields are going to migrate from cdev to cdev_priv
in the future in order to hide them.  A few fields may migrate
from devfs_dirent to cdev_priv as well.

Protect the DEVFS mountpoint with an sx lock instead of lockmgr,
this lock also protects the directory tree of the mountpoint.

Give each mountpoint a unique integer index, allocated with unr.
Use it into an array of devfs_dirent pointers in each cdev_priv.
Initially the array points to a single element also inside cdev_priv,
but as more devfs instances are mounted, the array is extended with
malloc(9) as necessary when the filesystem populates its directory
tree.

Retire the cdev alias lists, the cdev_priv now know about all the
relevant devfs_dirents (and their vnodes) and devfs_revoke() will
pick them up from there.  We still spelunk into other mountpoints
and fondle their data without 100% good locking.  It may make better
sense to vector the revoke event into the tty code and there do a
destroy_dev/make_dev on the tty's devices, but that's for further
study.

Lots of shuffling of stuff and churn of bits for no good reason[2].

XXX: There is still nothing preventing the dev_clone EVENTHANDLER
from being invoked at the same time in two devfs mountpoints.  It
is not obvious what the best course of action is here.

XXX: comment out an if statement that lost its body, until I can
find out what should go there so it doesn't do damage in the meantime.

XXX: Leave in a few extra malloc types and KASSERTS to help track
down any remaining issues.

Much testing provided by:		Kris
Much confusion caused by (races in):	md(4)

[1] You are not supposed to understand anything past this point.

[2] This line should simplify life for the peanut gallery.
2005-09-19 19:56:48 +00:00
phk
2d4ad1cc44 Don't attempt to recurse lockmgr, it doesn't like it. 2005-09-15 21:16:43 +00:00
phk
3c4b94c1fe Various minor polishing. 2005-09-15 10:28:19 +00:00
phk
a543c5b761 Close a race which could result in unwarranted "ruleset %d already
running" panics.

Previously, recursion through the "include" feature was prevented by
marking each ruleset as "running" when applied.  This doesn't work for
the case where two DEVFS instances try to apply the same ruleset at
the same time.

Instead introduce the sysctl vfs.devfs.rule_depth (default == 1) which
limits how many levels of "include" we will traverse.

Be aware that traversal of "include" is recursive and kernel stack
size is limited.

MFC:	after 3 days
2005-09-15 06:57:28 +00:00
phk
8a3fe94804 Collect the devfs related sysctls in one place 2005-08-16 19:25:02 +00:00
phk
e89ebd4119 Create a new internal .h file to communicate very private stuff
from kern_conf.c to devfs.

For now just two prototypes, more to come.
2005-08-16 19:08:01 +00:00
phk
4edc625526 Eliminate effectively unused dm_basedir field from devfs_mount. 2005-08-15 19:40:53 +00:00
rwatson
79690d711b When devfs cloning takes place, provide access to the credential of the
process that caused the clone event to take place for the device driver
creating the device.  This allows cloned device drivers to adapt the
device node based on security aspects of the process, such as the uid,
gid, and MAC label.

- Add a cred reference to struct cdev, so that when a device node is
  instantiated as a vnode, the cloning credential can be exposed to
  MAC.

- Add make_dev_cred(), a version of make_dev() that additionally
  accepts the credential to stick in the struct cdev.  Implement it and
  make_dev() in terms of a back-end make_dev_credv().

- Add a new event handler, dev_clone_cred, which can be registered to
  receive the credential instead of dev_clone, if desired.

- Modify the MAC entry point mac_create_devfs_device() to accept an
  optional credential pointer (may be NULL), so that MAC policies can
  inspect and act on the label or other elements of the credential
  when initializing the skeleton device protections.

- Modify tty_pty.c to register clone_dev_cred and invoke make_dev_cred(),
  so that the pty clone credential is exposed to the MAC Framework.

While currently primarily focussed on MAC policies, this change is also
a prerequisite for changes to allow ptys to be instantiated with the UID
of the process looking up the pty.  This requires further changes to the
pty driver -- in particular, to immediately recycle pty nodes on last
close so that the credential-related state can be recreated on next
lookup.

Submitted by:	Andrew Reisse <andrew.reisse@sparta.com>
Obtained from:	TrustedBSD Project
Sponsored by:	SPAWAR, SPARTA
MFC after:	1 week
MFC note:	Merge to 6.x, but not 5.x for ABI reasons
2005-07-14 10:22:09 +00:00
phk
2379f61770 cdev (still) needs per instance uid/gid/mode
Add unlocked version of dev_ref()

Clean up various stuff in sys/conf.h
2005-03-31 10:29:57 +00:00
phk
cfa6bb09ea Prepare for the final onslaught on devices:
Move uid/gid/mode from cdev to cdevsw.

Add kind field to use for devd(8) later.

Bump both D_VERSION and __FreeBSD_version
2005-03-17 12:07:00 +00:00
phk
75bcf4d381 Try to fix the mess I made of devname, with the minimal subset of the
larger minor/major patch which was posted for testing.
2005-03-10 18:21:34 +00:00
phk
9fbd4a503d Make a SYSCTL_NODE static 2005-02-10 12:23:29 +00:00
imp
fb0a393e99 /* -> /*- for copyright notices, minor format tweaks as necessary 2005-01-06 18:10:42 +00:00
phk
607546ee37 Reduce a fair bit of the atomics because we are now called with a
lock from kern_conf.c and cdev's act a lot more like real objects
these days.
2004-06-18 08:08:47 +00:00
phk
dfd1f7fd50 Do the dreaded s/dev_t/struct cdev */
Bump __FreeBSD_version accordingly.
2004-06-16 09:47:26 +00:00
phk
758f11d127 White-space align a struct definition.
Move a SYSINIT to the file where it belongs.
2004-02-15 21:43:08 +00:00
phk
4ad4dab84a NODEVFS cleanup:
Replace devfs_{create,destroy} hooks with direct function calls.
2003-03-02 13:35:30 +00:00
imp
cf874b345d Back out M_* changes, per decision of the TRB.
Approved by: trb
2003-02-19 05:47:46 +00:00
phk
98a90e953d NODEVFS cleanup: remove #ifdefs. 2003-01-29 22:36:45 +00:00
alfred
bf8e8a6e8f Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.
2003-01-21 08:56:16 +00:00
phk
24596ddb76 Originally when DEVFS was added, a global variable "devfs_present"
was used to control code which were conditional on DEVFS' precense
since this avoided the need for large-scale source pollution with
#include "opt_geom.h"

Now that we approach making DEVFS standard, replace these tests
with an #ifdef to facilitate mechanical removal once DEVFS becomes
non-optional.

No functional change by this commit.
2003-01-19 11:03:07 +00:00
rwatson
c5caffe9c4 Remove dm_root entry from struct devfs_mount. It's never set, and is
unused.  Replace it with a dm_mount back-pointer to the struct mount
that the devfs_mount is associated with.  Export that pointer to MAC
Framework entry points, where all current policies don't use the
pointer.  This permits the SEBSD port of SELinux's FLASK/TE to compile
out-of-the-box on 5.0-CURRENT with full file system labeling support.

Approved by:	re (murray)
Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-12-09 03:44:28 +00:00
phk
983b8bb673 s/struct dev_t */dev_t */ 2002-09-28 21:21:01 +00:00
rwatson
751f2d0c51 Introduce support for Mandatory Access Control and extensible
kernel access control.

Instrument devfs to support per-dirent MAC labels.  In particular,
invoke MAC framework when devfs directory entries are instantiated
due to make_dev() and related calls, and invoke the MAC framework
when vnodes are instantiated from these directory entries.  Implement
vop_setlabel() for devfs, which pushes the label update into the
devfs directory entry for semi-persistant store.  This permits the MAC
framework to assign labels to devices and directories as they are
instantiated, and export access control information via devfs vnodes.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, NAI Labs
2002-07-31 15:45:16 +00:00
dd
9498a983a9 Introduce the DEVFS "rule" subsystem. DEVFS rules permit the
administrator to define certain properties of new devfs nodes before
they become visible to the userland.  Both static (e.g., /dev/speaker)
and dynamic (e.g., /dev/bpf*, some removable devices) nodes are
supported.  Each DEVFS mount may have a different ruleset assigned to
it, permitting different policies to be implemented for things like
jails.

Approved by:	phk
2002-07-17 01:46:48 +00:00
msmith
c2656ac96b Add a new sysinit SI_SUB_DEVFS. Devfs hooks into the kernel at SI_ORDER_FIRST,
and devices can be created anytime after that.

Print a warning if an atttempt is made to create a device too early.
2002-01-09 04:58:49 +00:00