Commit Graph

289 Commits

Author SHA1 Message Date
Ed Schouten
7cbef24e1a Prefer __containerof() above member2struct().
The first does proper checking of the argument types, while the latter
does not.
2012-09-15 19:28:54 +00:00
Hans Petter Selasky
07da61a6cc Streamline use of cdevpriv and correct some corner cases.
1) It is not useful to call "devfs_clear_cdevpriv()" from
"d_close" callbacks, hence for example read, write, ioctl and
so on might be sleeping at the time of "d_close" being called
and then then freed private data can still be accessed.
Examples: dtrace, linux_compat, ksyms (all fixed by this patch)

2) In sys/dev/drm* there are some cases in which memory will
be freed twice, if open fails, first by code in the open
routine, secondly by the cdevpriv destructor. Move registration
of the cdevpriv to the end of the drm open routines.

3) devfs_clear_cdevpriv() is not called if the "d_open" callback
registered cdevpriv data and the "d_open" callback function
returned an error. Fix this.

Discussed with:	phk
MFC after:	2 weeks
2012-08-15 16:19:39 +00:00
Konstantin Belousov
c5c1199c83 Extend the KPI to lock and unlock f_offset member of struct file. It
now fully encapsulates all accesses to f_offset, and extends f_offset
locking to other consumers that need it, in particular, to lseek() and
variants of getdirentries().

Ensure that on 32bit architectures f_offset, which is 64bit quantity,
always read and written under the mtxpool protection. This fixes
apparently easy to trigger race when parallel lseek()s or lseek() and
read/write could destroy file offset.

The already broken ABI emulations, including iBCS and SysV, are not
converted (yet).

Tested by:	pho
No objections from:	jhb
MFC after:    3 weeks
2012-07-02 21:01:03 +00:00
Alexander Motin
d499701b0c Revert devfs part of r235911. I was unaware about old but unfinished
discussion between kib@ and gibbs@ about it.
2012-05-24 18:19:23 +00:00
Alexander Motin
f6ad3f237a MFprojects/zfsd:
Revamp the CAM enclosure services driver.
This updated driver uses an in-kernel daemon to track state changes and
publishes physical path location information\for disk elements into the
CAM device database.

Sponsored by:   Spectra Logic Corporation
Sponsored by:   iXsystems, Inc.
Submitted by:   gibbs, will, mav
2012-05-24 14:07:44 +00:00
Martin Matuska
b362f0a78b Add "export" to devfs_opts[] and return EOPNOTSUPP if called with it.
Fixes mountd warnings.

Reported by:	kib
MFC after:	1 week
2012-02-29 16:16:36 +00:00
Martin Matuska
bf3db8aa65 To improve control over the use of mount(8) inside a jail(8), introduce
a new jail parameter node with the following parameters:

allow.mount.devfs:
	allow mounting the devfs filesystem inside a jail

allow.mount.nullfs:
	allow mounting the nullfs filesystem inside a jail

Both parameters are disabled by default (equals the behavior before
devfs and nullfs in jails). Administrators have to explicitly allow
mounting devfs and nullfs for each jail. The value "-1" of the
devfs_ruleset parameter is removed in favor of the new allow setting.

Reviewed by:	jamie
Suggested by:	pjd
MFC after:	2 weeks
2012-02-23 18:51:24 +00:00
Konstantin Belousov
526d0bd547 Fix found places where uio_resid is truncated to int.
Add the sysctl debug.iosize_max_clamp, enabled by default. Setting the
sysctl to zero allows to perform the SSIZE_MAX-sized i/o requests from
the usermode.

Discussed with:	bde, das (previous versions)
MFC after:	1 month
2012-02-21 01:05:12 +00:00
Ed Schouten
8fac9b7b7d Merge si_name and __si_namebuf.
The si_name pointer always points to the __si_namebuf member inside the
same object. Remove it and rename __si_namebuf to si_name.
2012-02-10 12:40:50 +00:00
Martin Matuska
0cc207a6f5 Add support for mounting devfs inside jails.
A new jail(8) option "devfs_ruleset" defines the ruleset enforcement for
mounting devfs inside jails. A value of -1 disables mounting devfs in
jails, a value of zero means no restrictions. Nested jails can only
have mounting devfs disabled or inherit parent's enforcement as jails are
not allowed to view or manipulate devfs(8) rules.

Utilizes new functions introduced in r231265.

Reviewed by:	jamie
MFC after:	1 month
2012-02-09 10:22:08 +00:00
Martin Matuska
17d84d611f Introduce the "ruleset=number" option for devfs(5) mounts.
Add support for updating the devfs mount (currently only changing the
ruleset number is supported).
Check mnt_optnew with vfs_filteropt(9).

This new option sets the specified ruleset number as the active ruleset
of the new devfs mount and applies all its rules at mount time. If the
specified ruleset doesn't exist, a new empty ruleset is created.

MFC after:	1 month
2012-02-09 10:09:12 +00:00
John Baldwin
e517e6f12c Explicitly use curthread while manipulating td_fpop during last close
of a devfs file descriptor in devfs_close_f().  The passed in td argument
may be NULL if the close was invoked by garbage collection of open
file descriptors in pending control messages in the socket buffer of a
UNIX domain socket after it was closed.

PR:		kern/151758
Submitted by:	Andrey Shidakov  andrey shidakov ru
Submitted by:	Ruben van Staveren  ruben verweg com
Reviewed by:	kib
MFC after:	2 weeks
2011-12-09 17:49:34 +00:00
Konstantin Belousov
f82360acf2 Existing VOP_VPTOCNP() interface has a fatal flow that is critical for
nullfs.  The problem is that resulting vnode is only required to be
held on return from the successfull call to vop, instead of being
referenced.

Nullfs VOP_INACTIVE() method reclaims the vnode, which in combination
with the VOP_VPTOCNP() interface means that the directory vnode
returned from VOP_VPTOCNP() is reclaimed in advance, causing
vn_fullpath() to error with EBADF or like.

Change the interface for VOP_VPTOCNP(), now the dvp must be
referenced. Convert all in-tree implementations of VOP_VPTOCNP(),
which is trivial, because vhold(9) and vref(9) are similar in the
locking prerequisites. Out-of-tree fs implementation of VOP_VPTOCNP(),
if any, should have no trouble with the fix.

Tested by:	pho
Reviewed by:	mckusick
MFC after:	3 weeks (subject of re approval)
2011-11-19 07:50:49 +00:00
Eitan Adler
3b6dc18ef5 - fix duplicate "a a" in some comments
Submitted by:	eadler
Approved by:	simon
MFC after:	3 days
2011-11-13 17:06:33 +00:00
John Baldwin
dccc45e4c0 Move the cleanup of f_cdevpriv when the reference count of a devfs
file descriptor drops to zero out of _fdrop() and into devfs_close_f()
as it is only relevant for devfs file descriptors.

Reviewed by:	kib
MFC after:	1 week
2011-11-04 03:39:31 +00:00
Konstantin Belousov
1fef78c3f0 Fix kernel panic when d_fdopen csw method is called for NULL fp.
This may happen when kernel consumer calls VOP_OPEN().

Reported by:	Tavis Ormandy <taviso  cmpxchg8b com> through delphij
MFC after:	3 days
2011-11-03 18:55:18 +00:00
Konstantin Belousov
084e62e91b Export devfs inode number allocator for the kernel consumers.
Reviewed by:	jhb
MFC after:	2 weeks
2011-10-05 16:50:15 +00:00
Konstantin Belousov
9c00bb9190 Add the fo_chown and fo_chmod methods to struct fileops and use them
to implement fchown(2) and fchmod(2) support for several file types
that previously lacked it. Add MAC entries for chown/chmod done on
posix shared memory and (old) in-kernel posix semaphores.

Based on the submission by:	glebius
Reviewed by:	rwatson
Approved by:	re (bz)
2011-08-16 20:07:47 +00:00
Konstantin Belousov
e047ade947 Do not update mountpoint generation counter to the value which was not
yet acted upon by devfs_populate().

Submitted by:	Kohji Okuno <okuno.kohji jp panasonic com>
Approved by:	re (bz)
MFC after:	1 week
2011-08-09 20:53:33 +00:00
Konstantin Belousov
724ce55b5b While fixing the looping of a thread while devfs vnode is reclaimed,
r179247 introduced a possibility of devfs_allocv() returning spurious
ENOENT. If the vnode is selected by vnlru daemon for reclamation, then
devfs_allocv() can get ENOENT from vget() due to devfs_close() dropping
vnode lock around the call to cdevsw d_close method.

Use LK_RETRY in the vget() call, and do some part of the devfs_reclaim()
work in devfs_allocv(), clearing vp->v_data and de->de_vnode. Retry the
allocation of the vnode, now with de->de_vnode == NULL.

The check vp->v_data == NULL at the start of devfs_close() cannot be
affected by the change, since vnode lock must be held while VI_DOOMED
is set, and only dropped after the check.

Reported and tested by:	Kohji Okuno <okuno.kohji jp panasonic com>
Reviewed by:	attilio
MFC after:	3 weeks
2011-07-13 21:07:41 +00:00
Jaakko Heinonen
2d843e7d34 Don't allow user created symbolic links to cover another entries marked
with DE_USER. If a devfs rule hid such entry, it was possible to create
infinite number of symbolic links with the same name.

Reviewed by:	kib
2010-12-15 16:49:47 +00:00
Jaakko Heinonen
ef456eec95 - 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
Jaakko Heinonen
2f66e90fc7 Handle the special ruleset 0 in devfs_ruleset_use(). An attempt set the
current ruleset to 0 with command "devfs ruleset 0" triggered a KASSERT
in devfs_ruleset_create().

PR:		kern/125030
Submitted by:	Mateusz Guzik
2010-12-12 08:52:13 +00:00
Jaakko Heinonen
27877c9903 Format prototypes to follow style(9) more closely.
Discussed with:	kib, phk
2010-10-12 15:58:52 +00:00
Jaakko Heinonen
47bcfb6422 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
Jaakko Heinonen
d318c565d7 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
Jaakko Heinonen
6adc52306a Modify devfs_fqpn() for future use in devfs path reference counting
code:

- Accept devfs_mount and devfs_dirent as the arguments instead of a
  vnode. This generalizes the function so that it can be used from
  contexts where vnode references are not available.
- Accept NULL cnp argument. No '/' will be appended, if a NULL cnp is
  provided.
- Make the function global and add its prototype to devfs.h.

Reviewed by:	kib
2010-09-21 16:49:02 +00:00
Jaakko Heinonen
8570d045e5 - 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
Jaakko Heinonen
89d10571db 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
Jaakko Heinonen
4136388a18 Set de_dir for user created symbolic links. This will be needed to be
able to resolve their parent directories.
2010-08-26 16:01:29 +00:00
Jaakko Heinonen
f5efcd64f4 Call devfs_populate_vp() from devfs_getattr(). It was possible that
fstat(2) returned stale information through an open file descriptor.
2010-08-25 15:29:12 +00:00
Jaakko Heinonen
0f6bb099ae Introduce and use devfs_populate_vp() to unlock a vnode before calling
devfs_populate(). This is a prerequisite for the automatic removal of
empty directories which will be committed in the future.

Reviewed by:	kib (previous version)
2010-08-22 16:08:12 +00:00
John Baldwin
3634d5b241 Add dedicated routines to toggle lockmgr flags such as LK_NOSHARE and
LK_CANRECURSE after a lock is created.  Use them to implement macros that
otherwise manipulated the flags directly.  Assert that the associated
lockmgr lock is exclusively locked by the current thread when manipulating
these flags to ensure the flag updates are safe.  This last change required
some minor shuffling in a few filesystems to exclusively lock a brand new
vnode slightly earlier.

Reviewed by:	kib
MFC after:	3 days
2010-08-20 19:46:50 +00:00
Jaakko Heinonen
96835d61b6 Call dev_rel() in error paths.
Reported by:	kib
Reviewed by:	kib
MFC after:	2 weeks
2010-08-19 16:39:00 +00:00
Jaakko Heinonen
64040d3978 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
Konstantin Belousov
d3c5a40780 Enable shared lookups and externed shared ops for devfs.
In collaboration with:	pho
MFC after:	1 month
2010-08-06 09:46:53 +00:00
Konstantin Belousov
3979450b4c Add new make_dev_p(9) flag MAKEDEV_ETERNAL to inform devfs that created
cdev will never be destroyed. Propagate the flag to devfs vnodes as
VV_ETERNVALDEV. Use the flags to avoid acquiring devmtx and taking a
thread reference on such nodes.

In collaboration with:	pho
MFC after:	1 month
2010-08-06 09:42:15 +00:00
Konstantin Belousov
9968a42675 Enable shared locks for the devfs vnodes. Honor the locking mode
requested by lookup(). This should be a nop at the moment.

In collaboration with:	pho
MFC after:	1 month
2010-08-06 09:23:47 +00:00
Konstantin Belousov
3a6fc63c9f Initialize VV_ISTTY vnode flag on the devfs vnode creation instead of
doing it on each open.

In collaboration with:	pho
MFC after:	1 month
2010-08-06 09:06:55 +00:00
Jaakko Heinonen
f40645c83d 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
Jaakko Heinonen
59e0452e82 Don't try to call cdevsw d_close() method when devfs_close() is called
because of insmntque1() failure.

Found with:	stress2
Suggested and reviewed by:	kib
2010-06-01 18:57:21 +00:00
Konstantin Belousov
d2ba618a63 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
Jaakko Heinonen
17f820725e Revert r206560. The change doesn't work correctly in all cases with
multiple devfs mounts.
2010-04-16 07:02:28 +00:00
Jaakko Heinonen
70781bf94e - 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 Schouten
bf2296be8b 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
Ed Schouten
8dc9b4cf04 Let access overriding to TTYs depend on the cdev_priv, not the vnode.
Basically this commit changes two things, which improves access to TTYs
in exceptional conditions. Basically the problem was that when you ran
jexec(8) to attach to a jail, you couldn't use /dev/tty (well, also the
node of the actual TTY, e.g. /dev/pts/X). This is very inconvenient if
you want to attach to screens quickly, use ssh(1), etc.

The fixes:

- Cache the cdev_priv of the controlling TTY in struct session. Change
  devfs_access() to compare against the cdev_priv instead of the vnode.
  This allows you to bypass UNIX permissions, even across different
  mounts of devfs.

- Extend devfs_prison_check() to unconditionally expose the device node
  of the controlling TTY, even if normal prison nesting rules normally
  don't allow this. This actually allows you to interact with this
  device node.

To be honest, I'm not really happy with this solution. We now have to
store three pointers to a controlling TTY (s_ttyp, s_ttyvp, s_ttydp).
In an ideal world, we should just get rid of the latter two and only use
s_ttyp, but this makes certian pieces of code very impractical (e.g.
devfs, kern_exit.c).

Reported by:	Many people
2009-12-19 18:42:12 +00:00
Ed Schouten
f8f6146082 Improve nested jail awareness of devfs by handling credentials.
Now that we start to use credentials on character devices more often
(because of MPSAFE TTY), move the prison-checks that are in place in the
TTY code into devfs.

Instead of strictly comparing the prisons, use the more common
prison_check() function to compare credentials. This means that
pseudo-terminals are only visible in devfs by processes within the same
jail and parent jails.

Even though regular users in parent jails can now interact with
pseudo-terminals from child jails, this seems to be the right approach.
These processes are also capable of interacting with the jailed
processes anyway, through signals for example.

Reviewed by:	kib, rwatson (older version)
2009-06-20 14:50:32 +00:00
Konstantin Belousov
c4df27d5c8 VOP_IOCTL takes unlocked vnode as an argument. Due to this, v_data may
be NULL or derefenced memory may become free at arbitrary moment.

Lock the vnode in cd9660, devfs and pseudofs implementation of VOP_IOCTL
to prevent reclaim; check whether the vnode was already reclaimed after
the lock is granted.

Reported by:	georg at dts su
Reviewed by:	des (pseudofs)
MFC after:	2 weeks
2009-06-10 13:57:36 +00:00
Robert Watson
bcf11e8d00 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
Robert Watson
927e0a56ce Re-add opt_mac.h include, which is required in order for MNT_MULTILABEL
to be set properly on devfs.  Otherwise, it isn't possible to set labels
on /dev nodes.

Reported by:	Sergio Rodriguez <sergiorr at yahoo.com>
MFC after:	3 days
2009-06-04 10:30:18 +00:00