Commit Graph

93 Commits

Author SHA1 Message Date
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
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
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
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
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
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
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
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
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
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
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
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
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
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
6a33fe5e57 Avoid "unused variable" warning when building without PSEUDOFS_TRACE. 2007-04-15 20:35:18 +00:00
des
4632956a5b Make pseudofs (and consequently procfs, linprocfs and linsysfs) MPSAFE. 2007-04-15 17:10:01 +00:00
des
8dea6eb551 Further pseudofs improvements:
The pfs_info mutex is only needed to lock pi_unrhdr.  Everything else
in struct pfs_info is modified only while Giant is held (during
vfs_init() / vfs_uninit()); add assertions to that effect.

Simplify pfs_destroy somewhat.

Remove superfluous arguments from pfs_fileno_{alloc,free}(), and the
assertions which were added in the previous commit to ensure they were
consistent.

Assert that Giant is held while the vnode cache is initialized and
destroyed.  Also assert that the cache is empty when it is destroyed.

Rename the vnode cache mutex for consistency.

Fix a long-standing bug in pfs_getattr(): it would uncritically return
the node's pn_fileno as st_ino.  This would result in st_ino being 0
if the node had not previously been visited by readdir(), and also in
an incorrect st_ino for process directories and any files contained
therein.  Correct this by abstracting the fileno manipulations
previously done in pfs_readdir() into a new function, pfs_fileno(),
which is used by both pfs_getattr() and pfs_readdir().
2007-04-14 14:08:30 +00:00
netchild
1fbdab64b8 Correctly calculate a buffer length. It was off by one so a read() returned
one byte less than needed.

This is a RELENG_x_y candidate, since it fixes a problem with Oracle 10.

Noticed by:	Dmitry Ganenko <dima@apk-inform.com>
Testcase by:	Dmitry Ganenko <dima@apk-inform.com>
Reviewed by:	des
Submitted by:	rdivacky
Sponsored by:	Google SoC 2006
MFC after:	1 week
2006-06-27 20:21:38 +00:00
jhb
ff9c76bccd Close some races between procfs/ptrace and exit(2):
- Reorder the events in exit(2) slightly so that we trigger the S_EXIT
  stop event earlier.  After we have signalled that, we set P_WEXIT and
  then wait for any processes with a hold on the vmspace via PHOLD to
  release it.  PHOLD now KASSERT()'s that P_WEXIT is clear when it is
  invoked, and PRELE now does a wakeup if P_WEXIT is set and p_lock drops
  to zero.
- Change proc_rwmem() to require that the processing read from has its
  vmspace held via PHOLD by the caller and get rid of all the junk to
  screw around with the vmspace reference count as we no longer need it.
- In ptrace() and pseudofs(), treat a process with P_WEXIT set as if it
  doesn't exist.
- Only do one PHOLD in kern_ptrace() now, and do it earlier so it covers
  FIX_SSTEP() (since on alpha at least this can end up calling proc_rwmem()
  to clear an earlier single-step simualted via a breakpoint).  We only
  do one to avoid races.  Also, by making the EINVAL error for unknown
  requests be part of the default: case in the switch, the various
  switch cases can now just break out to return which removes a _lot_ of
  duplicated PRELE and proc unlocks, etc.  Also, it fixes at least one bug
  where a LWP ptrace command could return EINVAL with the proc lock still
  held.
- Changed the locking for ptrace_single_step(), ptrace_set_pc(), and
  ptrace_clear_single_step() to always be called with the proc lock
  held (it was a mixed bag previously).  Alpha and arm have to drop
  the lock while the mess around with breakpoints, but other archs
  avoid extra lock release/acquires in ptrace().  I did have to fix a
  couple of other consumers in kern_kse and a few other places to
  hold the proc lock and PHOLD.

Tested by:	ps (1 mostly, but some bits of 2-4 as well)
MFC after:	1 week
2006-02-22 18:57:50 +00:00
jhb
82b4c89720 Change pfs_visible() to optionally return a pointer to the process
associated with the passed in pfs_node.  If it does return a pointer, it
keeps the process locked.  This allows a lot of places that were calling
pfind() again right after pfs_visible() to not have to do that and avoids
races since we don't drop the proc lock just to turn around and lock it
again.  This will become more important with future changes to fix races
between procfs/ptrace and exit(2).  Also, removed a duplicate pfs_visible()
call in pfs_getextattr().

Reviewed by:	des
MFC after:	1 week
2006-02-22 17:24:54 +00:00
des
5610061cd3 Eliminate an unnecessary bcopy(). 2005-08-12 12:22:05 +00:00
des
fe9d4ac270 Fix an old pasto. 2005-04-30 16:27:20 +00:00
jeff
afab3762a0 - Change all filesystems and vfs_cache to relock the dvp once the child is
locked in the ISDOTDOT case.  Se vfs_lookup.c r1.79 for details.

Sponsored by:	Isilon Systems, Inc.
2005-04-13 10:59:09 +00:00
jeff
b136fd4eee - We no longer have to bother with PDIRUNLOCK, lookup() handles it for us.
Sponsored by:   Isilon Systems, Inc.
2005-03-28 09:34:36 +00:00
des
8bd55ce9cb Hook pfs_lookup() up to vfs_cachedlookup_desc instead of vfs_lookup_desc,
as suggested by Matt's comment.  Also fix some style and paranoia issues.

The entire function could benefit from review by a VFS guru.

MFC after:	6 weeks
2005-03-14 16:24:50 +00:00
des
aa287f3e12 Fix two long-standing bugs in pfs_readdir():
Since we used an sbuf of size resid to accumulate dirents, we would end
up returning one byte short when we had enough dirents to fill or exceed
the size of the sbuf (the last byte being lost to bogus NUL termination)
causing the next call to return EINVAL due to an unaligned offset.  This
went undetected for a long time because I did most of my testing in
single-user mode, where there are rarely enough processes to fill the
4096-byte buffer ls(1) uses.  The most common symptom of this bug is that
tab completion of /proc or /compat/linux/proc does not work properly when
many processes are running.

Also, a check near the top would return EINVAL if resid was smaller than
PFS_DELEN, even if it was 0, which is frequently the case and perfectly
allowable.  Change the test so that it returns 0 if resid is 0.

MFC after:	2 weeks
2005-03-14 16:21:32 +00:00
des
892fcdb014 If PSEUDOFS_TRACE is defined, create a sysctl knob to enable / disable
pseudofs call tracing.
2005-03-14 16:06:47 +00:00
des
cae8560557 fbsdidize. 2005-03-14 15:54:11 +00:00
phk
7617afd15d Whitespace in vop_vector{} initializations. 2005-01-13 18:59:48 +00:00
kan
17bd3d9149 Fix a typo in PFS_TRACE.
PR:		kern/74461
Submitted by:	Craig Rodrigues <rodrigc at crodrigues.org>
2004-12-06 20:07:17 +00:00
phk
59f305606c Back when VOP_* was introduced, we did not have new-style struct
initializations but we did have lofty goals and big ideals.

Adjust to more contemporary circumstances and gain type checking.

	Replace the entire vop_t frobbing thing with properly typed
	structures.  The only casualty is that we can not add a new
	VOP_ method with a loadable module.  History has not given
	us reason to belive this would ever be feasible in the the
	first place.

	Eliminate in toto VOCALL(), vop_t, VNODEOP_SET() etc.

	Give coda correct prototypes and function definitions for
	all vop_()s.

	Generate a bit more data from the vnode_if.src file:  a
	struct vop_vector and protype typedefs for all vop methods.

	Add a new vop_bypass() and make vop_default be a pointer
	to another struct vop_vector.

	Remove a lot of vfs_init since vop_vector is ready to use
	from the compiler.

	Cast various vop_mumble() to void * with uppercase name,
	for instance VOP_PANIC, VOP_NULL etc.

	Implement VCALL() by making vdesc_offset the offsetof() the
	relevant function pointer in vop_vector.  This is disgusting
	but since the code is generated by a script comparatively
	safe.  The alternative for nullfs etc. would be much worse.

	Fix up all vnode method vectors to remove casts so they
	become typesafe.  (The bulk of this is generated by scripts)
2004-12-01 23:16:38 +00:00
rwatson
7634ea5ca7 Back out pseudo_vnops.c:1.45, which was a workaround for pfind()
returning incompletely initialized processes.  This problem was
eliminated by kern_proc.c:1.215, which causes pfind() not to
return processes in the PRS_NEW state.
2004-09-02 16:04:09 +00:00
rwatson
6994ab16ad Commit a work-around for a more general bug involving process state:
check whether p_ucred is NULL or not in pfs_getattr() before
dereferencing the credential, and return ENOENT if there wasn't one.

This is a symptom of a larger problem, wherein pfind() can return
references to incompletely initialized processes, and we instead ought
to not return them, or check the process state before acting on the
process.

Reported by:	kris
Discussed with:	tjr, others
2004-08-13 20:27:56 +00:00
des
881a348b52 Accumulate directory entries in a fixed-length sbuf, and uiomove them in
one go before returning.  This avoids calling uiomove() while holding
allproc_lock.

Don't adjust uio->uio_offset manually, uiomove() does that for us.

Don't drop allproc_lock before calling panic().

Suggested by:	alfred
2004-07-09 11:43:37 +00:00