Commit Graph

159 Commits

Author SHA1 Message Date
kib
6092948278 Remove Giant asserts. Update comment.
Owning Giant in the init/uninit is accidental due to the moment where
VFS modules initialization is performed, and is not enforced by the
VFS interface.  The Giant lock does not prevent a parallel execution
of the code, it is VFS which implements the proper protocol.

Approved by:	des (pseudofs maintainer)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2016-08-03 08:57:15 +00:00
kib
5567fc3cb5 Some style changes. Fix a typo in comment.
Approved by:	des (pseudofs maintainer)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2016-08-03 08:53:29 +00:00
kib
ef2ed17f02 Do not perform unneccessary shared recursion on the allproc_lock in
pfs_visible().  The recursion does not cause deadlock because the sx
implementation does not prefer exclusive waiters over the shared, but
this is an implementation detail.

Reported by:	pho, Matthew Bryan <matthew.bryan@isilon.com>
Reviewed by:	jhb
Tested by:	pho
Approved by:	des (pseudofs maintainer)
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
2016-03-11 11:51:38 +00:00
dchagin
4e888d6b57 Hide vfs.pfs.trace variable if it is not used. 2015-05-24 18:11:22 +00:00
kib
e4deb800b0 Redo r258088 to avoid relying on signed arithmetic overflow, since
compiler interprets this as an undefined behaviour.  Instead, ensure
that the sum of uio_offset and uio_resid is below OFF_MAX using the
operation which cannot overflow.

Reported and tested by:	pho
Discussed with:	bde
Approved by:	des (pseudofs maintainer)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2013-11-20 19:41:00 +00:00
kib
2e0b8010f9 Remove useless comparisions of assigned offset and resid with the
sources from uio.  Both uio_offset and offset, and uio_resid and resid
have the same types for some time.

Add check for buflen overflow by comparing the buflen with both offset
and resid (vs. comparing with offset only, as it is currently done).

Reported and tested by:	pho
Approved by:	des (pseudofs maintainer)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2013-11-13 08:55:09 +00:00
attilio
d5d551ec46 Complete MPSAFE VFS interface and remove MNTK_MPSAFE flag.
Porters should refer to __FreeBSD_version 1000021 for this change as
it may have happened at the same timeframe.
2012-11-09 18:02:25 +00:00
kib
91747da5db Apply inlined vn_vget_ino() algorithm for ".." lookup in pseudofs.
Reported and tested by:	pho
MFC after:	2 weeks
2012-03-05 11:38:02 +00:00
mm
77766742e1 Add procfs to jail-mountable filesystems.
Reviewed by:	jamie
MFC after:	1 week
2012-02-29 00:30:18 +00:00
kib
80ae8fe82c 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
mckusick
af2e331939 Make sure all intermediate variables holding mount flags (mnt_flag)
and that all internal kernel calls passing mount flags are declared
as uint64_t so that flags in the top 32-bits are not lost.

MFC after: 2 weeks
2012-01-17 01:08:01 +00:00
uqs
d61d88a310 Convert files to UTF-8 2012-01-15 13:23:18 +00:00
jh
6417e1b242 r222004 changed sbuf_finish() to not clear the buffer error status. As a
consequence sbuf_len() will return -1 for buffers which had the error
status set prior to sbuf_finish() call. This causes a problem in
pfs_read() which purposely uses a fixed size sbuf to discard bytes which
are not needed to fulfill the read request.

Work around the problem by using the full buffer length when
sbuf_finish() indicates an overflow. An overflowed sbuf with fixed size
is always full.

PR:		kern/163076
Approved by:	des
MFC after:	2 weeks
2012-01-06 10:12:59 +00:00
jh
3ff26fa74b Check the return value of sbuf_finish() in pfs_readlink() and return
ENAMETOOLONG if the buffer overflowed.

Approved by:	des
MFC after:	2 weeks
2012-01-06 09:17:34 +00:00
kib
36fd8d0106 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
kib
8db316e707 Fix build, use %d for int value formatting. 2011-11-16 18:41:59 +00:00
pho
e92770644f Handle invalid large values for getdirentries(2) data buffer size.
In collaboration with:	kib
Reviewed by:	des
Reported by:	The iknowthis syscall fuzzer.
MFC after:	1 week
2011-11-16 10:11:55 +00:00
pho
6a35ddd54a Removed extra PRELE() call.
MFC after:	1 week
2011-11-15 09:23:21 +00:00
ed
0c56cf839d Mark all SYSCTL_NODEs static that have no corresponding SYSCTL_DECLs.
The SYSCTL_NODE macro defines a list that stores all child-elements of
that node. If there's no SYSCTL_DECL macro anywhere else, there's no
reason why it shouldn't be static.
2011-11-07 15:43:11 +00:00
jhb
d4890c88b0 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
kib
d5b92466a9 The cache_enter(9) function shall not be called for doomed dvp.
Assert this.

In the reported panic, vdestroy() fired the assertion "vp has namecache
for ..", because pseudofs may end up doing cache_enter() with reclaimed
dvp, after dotdot lookup temporary unlocked dvp.
Similar problem exists in ufs_lookup() for "." lookup, when vnode
lock needs to be upgraded.

Verify that dvp is not reclaimed before calling cache_enter().

Reported and tested by:	pho
Reviewed by:	kan
MFC after:	2 weeks
2010-04-20 10:19:27 +00:00
jh
03418e0c50 Truncate read request rather than returning EIO if the request is
larger than MAXPHYS + 1. This fixes a problem with cat(1) when it
uses a large I/O buffer.

Reported by:	Fernando Apesteguía
Suggested by:	jilles
Reviewed by:	des
Approved by:	trasz (mentor)
2010-01-22 08:45:12 +00:00
kib
8aa65727e7 If a race is detected, pfs_vncache_alloc() may reclaim a vnode that had
never been inserted into the pfs_vncache list. Since pfs_vncache_free()
does not anticipate this case, it decrements pfs_vncache_entries
unconditionally; if the vnode was not in the list, pfs_vncache_entries
will no longer reflect the actual number of list entries. This may cause
size of the cache to exceed the configured maximum. It may also trigger
a panic during module unload or system shutdown.

Do not decrement pfs_vncache_entries for the vnode that was not in the
list.

Submitted by:	tegge
Reviewed by:	des
MFC after:	1 week
2009-09-07 12:10:41 +00:00
kib
30f476628e insmntque_stddtr() clears vp->v_data and resets vp->v_op to
dead_vnodeops before calling vgone(). Revert r189706 and corresponding
part of the r186560.

Noted and reviewed by:	tegge
Approved by:	des (pseudofs part)
MFC after:	3 days
2009-09-07 11:55:34 +00:00
kib
06073946fa Remove spurious pfs_unlock().
PR:	kern/137310
Reviewed by:	des
MFC after:	3 days
2009-08-31 09:26:04 +00:00
kib
a7a5954511 Change the type of uio_resid member of struct uio from int to ssize_t.
Note that this does not actually enable full-range i/o requests for
64 architectures, and is done now to update KBI only.

Tested by:	pho
Reviewed by:	jhb, bde (as part of the review of the bigger patch)
2009-06-25 18:46:30 +00:00
kib
e0d7459c71 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
des
1e782303de Drop Giant.
MFC after:	1 week
2009-06-06 00:44:13 +00:00
kib
7d4b798303 Unlock the pseudofs vnode before calling fill method for pfs_readlink().
The fill code may need to lock another vnode, e.g. procfs file
implementation.

Reviewed by:	des
Tested by:	pho
MFC after:	2 weeks
2009-05-31 15:01:50 +00:00
des
e329742030 Use a temporary variable to avoid a duplicate strlen().
Submitted by:	kib
MFC after:	1 week
2009-05-28 10:24:26 +00:00
attilio
1dcb84131b Remove the thread argument from the FSD (File-System Dependent) parts of
the VFS.  Now all the VFS_* functions and relating parts don't want the
context as long as it always refers to curthread.

In some points, in particular when dealing with VOPs and functions living
in the same namespace (eg. vflush) which still need to be converted,
pass curthread explicitly in order to retain the old behaviour.
Such loose ends will be fixed ASAP.

While here fix a bug: now, UFS_EXTATTR can be compiled alone without the
UFS_EXTATTR_AUTOSTART option.

VFS KPI is heavilly changed by this commit so thirdy parts modules needs
to be recompiled.  Bump __FreeBSD_version in order to signal such
situation.
2009-05-11 15:33:26 +00:00
des
a4681f26ef Remove spurious locking in pfs_write().
Reported by:	Andrew Brampton <me@bramp.net>
MFC after:	1 week
2009-04-08 09:02:42 +00:00
des
3edfad09c6 Fix an inverted KASSERT. Add similar assertions in other similar places.
Reported by:	Andrew Brampton <me@bramp.net>
MFC after:	1 week
2009-04-07 16:13:10 +00:00
des
30905a5845 Fix a logic bug that caused the pfs_attr method to be called only for
PFS_PROCDEP nodes.

Submitted by:	Andrew Brampton <brampton@gmail.com>
MFC after:	2 weeks
2009-02-16 15:17:26 +00:00
marcus
267597236c Fix a deadlock which can occur due to a pseudofs vnode not getting unlocked.
Reported by:	Richard Todd <rmtodd@ichotolot.servalan.com>
Reviewed by:	kib
Approved by:	kib
2009-01-09 22:06:48 +00:00
marcus
0aba8d65ee Add a VOP_VPTOCNP implementation for pseudofs which covers file systems
such as procfs and linprocfs.

This implementation's locking was enhanced by kib.

Reviewed by:	kib
		des
Approved by:	des
		kib
Tested by:	pho
2008-12-30 21:49:39 +00:00
kib
0deec7e423 When the insmntque() in the pfs_vncache_alloc() fails, vop_reclaim calls
pfs_vncache_free() that removes pvd from the list, while it is not yet
put on the list.

Prevent the invalid removal from the list by clearing pvd_next and
pvd_prev for the newly allocated pvd, and only move pfs_vncache list
head when the pvd was at the head.

Suggested and approved by:	des
MFC after:	2 weeks
2008-12-29 13:25:58 +00:00
kib
7599f93972 Drop the pseudofs vnode lock around call to pfs_read handler. The handler
may need to lock arbitrary vnodes, causing either lock order reversal or
recursive vnode lock acquisition.

Tested by:	pho
Approved by:	des
MFC after:	2 weeks
2008-12-29 12:12:23 +00:00
kib
c3f2d023e8 After the pfs_vncache_mutex is dropped, another thread may attempt to
do pfs_vncache_alloc() for the same pfs_node and pid. In this case, we
could end up with two vnodes for the pair. Recheck the cache under the
locked pfs_vncache_mutex after all sleeping operations are done [1].

This case mostly cannot happen now because pseudofs uses exclusive vnode
locking for lookup. But it does drop the vnode lock for dotdot lookups,
and Marcus' pseudofs_vptocnp implementation is vulnerable too.

Do not call free() on the struct pfs_vdata after insmntque() failure,
because vp->v_data points to the structure, and pseudofs_reclaim()
frees it by the call to pfs_vncache_free().

Tested by:	pho [1]
Approved by:	des
MFC after:	2 weeks
2008-12-29 12:07:18 +00:00
trasz
0ad8692247 Introduce accmode_t. This is required for NFSv4 ACLs - it will be neccessary
to add more V* constants, and the variables changed by this patch were often
being assigned to mode_t variables, which is 16 bit.

Approved by:	rwatson (mentor)
2008-10-28 13:44:11 +00:00
des
66f807ed8b Retire the MALLOC and FREE macros. They are an abomination unto style(9).
MFC after:	3 months
2008-10-23 15:53:51 +00:00
kib
a127656dea fdescfs, devfs, mqueuefs, nfs, portalfs, pseudofs, tmpfs and xfs
initialize the vattr structure in VOP_GETATTR() with VATTR_NULL(),
vattr_null() or by zeroing it. Remove these to allow preinitialization
of fields work in vn_stat(). This is needed to get birthtime initialized
correctly.

Submitted by:   Jaakko Heinonen <jh saunalahti fi>
Discussed on:   freebsd-fs
MFC after:	1 month
2008-09-20 19:50:52 +00:00
attilio
dbf35e279f Decontextualize the couplet VOP_GETATTR / VOP_SETATTR as the passed thread
was always curthread and totally unuseful.

Tested by: Giovanni Trematerra <giovanni dot trematerra at gmail dot com>
2008-08-28 15:23:18 +00:00
attilio
0d54671a48 Introduce some functions in the vnode locks namespace and in the ffs
namespace in order to handle lockmgr fields in a controlled way instead
than spreading all around bogus stubs:
- VN_LOCK_AREC() allows lock recursion for a specified vnode
- VN_LOCK_ASHARE() allows lock sharing for a specified vnode

In FFS land:
- BUF_AREC() allows lock recursion for a specified buffer lock
- BUF_NOREC() disallows recursion for a specified buffer lock

Side note: union_subr.c::unionfs_node_update() is the only other function
directly handling lockmgr fields. As this is not simple to fix, it has
been left behind as "sole" exception.
2008-02-24 16:38:58 +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
alfred
3a60df401c Get rid of qaddr_t.
Requested by: bde
2007-10-16 10:54:55 +00:00
jhb
3739d97391 Use the correct pid when checking to see whether or not the /proc/<pid>
directory itself (rather than any of its contents) is visible to the
current thread.

MFC after:	1 week
PR:		kern/90063
Submitted by:	john of 8192.net
Approved by:	re (kensmith)
2007-10-05 17:37:25 +00:00
bmah
229a009b9d Fix off-by-one error (introduced in r1.60) that had the effect of
disallowing a read of exactly MAXPHYS bytes.

Reviewed by:	des, rdivacky
MFC after:	1 week
Sponsored by:	nCircle Network Security
2007-06-07 15:04:30 +00:00
des
d5a4cf1cbe Fix old locking bugs which were revealed when pseudofs was made MPSAFE.
Submitted by:	tegge
2007-04-23 19:17:01 +00:00