Commit Graph

658 Commits

Author SHA1 Message Date
Pawel Jakub Dawidek
d6b2bd0bc9 Style: Whitespace fixes. 2013-03-16 22:37:30 +00:00
Pawel Jakub Dawidek
1ea67dd9e5 Style: Remove redundant space. 2013-03-16 22:36:24 +00:00
Attilio Rao
89f6b8632c Switch the vm_object mutex to be a rwlock. This will enable in the
future further optimizations where the vm_object lock will be held
in read mode most of the time the page cache resident pool of pages
are accessed for reading purposes.

The change is mostly mechanical but few notes are reported:
* The KPI changes as follow:
  - VM_OBJECT_LOCK() -> VM_OBJECT_WLOCK()
  - VM_OBJECT_TRYLOCK() -> VM_OBJECT_TRYWLOCK()
  - VM_OBJECT_UNLOCK() -> VM_OBJECT_WUNLOCK()
  - VM_OBJECT_LOCK_ASSERT(MA_OWNED) -> VM_OBJECT_ASSERT_WLOCKED()
    (in order to avoid visibility of implementation details)
  - The read-mode operations are added:
    VM_OBJECT_RLOCK(), VM_OBJECT_TRYRLOCK(), VM_OBJECT_RUNLOCK(),
    VM_OBJECT_ASSERT_RLOCKED(), VM_OBJECT_ASSERT_LOCKED()
* The vm/vm_pager.h namespace pollution avoidance (forcing requiring
  sys/mutex.h in consumers directly to cater its inlining functions
  using VM_OBJECT_LOCK()) imposes that all the vm/vm_pager.h
  consumers now must include also sys/rwlock.h.
* zfs requires a quite convoluted fix to include FreeBSD rwlocks into
  the compat layer because the name clash between FreeBSD and solaris
  versions must be avoided.
  At this purpose zfs redefines the vm_object locking functions
  directly, isolating the FreeBSD components in specific compat stubs.

The KPI results heavilly broken by this commit.  Thirdy part ports must
be updated accordingly (I can think off-hand of VirtualBox, for example).

Sponsored by:	EMC / Isilon storage division
Reviewed by:	jeff
Reviewed by:	pjd (ZFS specific review)
Discussed with:	alc
Tested by:	pho
2013-03-09 02:32:23 +00:00
Pawel Jakub Dawidek
6d4e99aaef If the target file already exists, check for the CAP_UNLINKAT capabiity right
on the target directory descriptor, but only if this is renameat(2) and real
target directory descriptor is given (not AT_FDCWD). Without this fix regular
rename(2) fails if the target file already exists.

Reported by:	Michael Butler <imb@protected-networks.net>
Reported by:	Larry Rosenman <ler@lerctr.org>
Sponsored by:	The FreeBSD Foundation
2013-03-02 09:58:47 +00:00
Pawel Jakub Dawidek
2609222ab4 Merge Capsicum overhaul:
- Capability is no longer separate descriptor type. Now every descriptor
  has set of its own capability rights.

- The cap_new(2) system call is left, but it is no longer documented and
  should not be used in new code.

- The new syscall cap_rights_limit(2) should be used instead of
  cap_new(2), which limits capability rights of the given descriptor
  without creating a new one.

- The cap_getrights(2) syscall is renamed to cap_rights_get(2).

- If CAP_IOCTL capability right is present we can further reduce allowed
  ioctls list with the new cap_ioctls_limit(2) syscall. List of allowed
  ioctls can be retrived with cap_ioctls_get(2) syscall.

- If CAP_FCNTL capability right is present we can further reduce fcntls
  that can be used with the new cap_fcntls_limit(2) syscall and retrive
  them with cap_fcntls_get(2).

- To support ioctl and fcntl white-listing the filedesc structure was
  heavly modified.

- The audit subsystem, kdump and procstat tools were updated to
  recognize new syscalls.

- Capability rights were revised and eventhough I tried hard to provide
  backward API and ABI compatibility there are some incompatible changes
  that are described in detail below:

	CAP_CREATE old behaviour:
	- Allow for openat(2)+O_CREAT.
	- Allow for linkat(2).
	- Allow for symlinkat(2).
	CAP_CREATE new behaviour:
	- Allow for openat(2)+O_CREAT.

	Added CAP_LINKAT:
	- Allow for linkat(2). ABI: Reuses CAP_RMDIR bit.
	- Allow to be target for renameat(2).

	Added CAP_SYMLINKAT:
	- Allow for symlinkat(2).

	Removed CAP_DELETE. Old behaviour:
	- Allow for unlinkat(2) when removing non-directory object.
	- Allow to be source for renameat(2).

	Removed CAP_RMDIR. Old behaviour:
	- Allow for unlinkat(2) when removing directory.

	Added CAP_RENAMEAT:
	- Required for source directory for the renameat(2) syscall.

	Added CAP_UNLINKAT (effectively it replaces CAP_DELETE and CAP_RMDIR):
	- Allow for unlinkat(2) on any object.
	- Required if target of renameat(2) exists and will be removed by this
	  call.

	Removed CAP_MAPEXEC.

	CAP_MMAP old behaviour:
	- Allow for mmap(2) with any combination of PROT_NONE, PROT_READ and
	  PROT_WRITE.
	CAP_MMAP new behaviour:
	- Allow for mmap(2)+PROT_NONE.

	Added CAP_MMAP_R:
	- Allow for mmap(PROT_READ).
	Added CAP_MMAP_W:
	- Allow for mmap(PROT_WRITE).
	Added CAP_MMAP_X:
	- Allow for mmap(PROT_EXEC).
	Added CAP_MMAP_RW:
	- Allow for mmap(PROT_READ | PROT_WRITE).
	Added CAP_MMAP_RX:
	- Allow for mmap(PROT_READ | PROT_EXEC).
	Added CAP_MMAP_WX:
	- Allow for mmap(PROT_WRITE | PROT_EXEC).
	Added CAP_MMAP_RWX:
	- Allow for mmap(PROT_READ | PROT_WRITE | PROT_EXEC).

	Renamed CAP_MKDIR to CAP_MKDIRAT.
	Renamed CAP_MKFIFO to CAP_MKFIFOAT.
	Renamed CAP_MKNODE to CAP_MKNODEAT.

	CAP_READ old behaviour:
	- Allow pread(2).
	- Disallow read(2), readv(2) (if there is no CAP_SEEK).
	CAP_READ new behaviour:
	- Allow read(2), readv(2).
	- Disallow pread(2) (CAP_SEEK was also required).

	CAP_WRITE old behaviour:
	- Allow pwrite(2).
	- Disallow write(2), writev(2) (if there is no CAP_SEEK).
	CAP_WRITE new behaviour:
	- Allow write(2), writev(2).
	- Disallow pwrite(2) (CAP_SEEK was also required).

	Added convinient defines:

	#define	CAP_PREAD		(CAP_SEEK | CAP_READ)
	#define	CAP_PWRITE		(CAP_SEEK | CAP_WRITE)
	#define	CAP_MMAP_R		(CAP_MMAP | CAP_SEEK | CAP_READ)
	#define	CAP_MMAP_W		(CAP_MMAP | CAP_SEEK | CAP_WRITE)
	#define	CAP_MMAP_X		(CAP_MMAP | CAP_SEEK | 0x0000000000000008ULL)
	#define	CAP_MMAP_RW		(CAP_MMAP_R | CAP_MMAP_W)
	#define	CAP_MMAP_RX		(CAP_MMAP_R | CAP_MMAP_X)
	#define	CAP_MMAP_WX		(CAP_MMAP_W | CAP_MMAP_X)
	#define	CAP_MMAP_RWX		(CAP_MMAP_R | CAP_MMAP_W | CAP_MMAP_X)
	#define	CAP_RECV		CAP_READ
	#define	CAP_SEND		CAP_WRITE

	#define	CAP_SOCK_CLIENT \
		(CAP_CONNECT | CAP_GETPEERNAME | CAP_GETSOCKNAME | CAP_GETSOCKOPT | \
		 CAP_PEELOFF | CAP_RECV | CAP_SEND | CAP_SETSOCKOPT | CAP_SHUTDOWN)
	#define	CAP_SOCK_SERVER \
		(CAP_ACCEPT | CAP_BIND | CAP_GETPEERNAME | CAP_GETSOCKNAME | \
		 CAP_GETSOCKOPT | CAP_LISTEN | CAP_PEELOFF | CAP_RECV | CAP_SEND | \
		 CAP_SETSOCKOPT | CAP_SHUTDOWN)

	Added defines for backward API compatibility:

	#define	CAP_MAPEXEC		CAP_MMAP_X
	#define	CAP_DELETE		CAP_UNLINKAT
	#define	CAP_MKDIR		CAP_MKDIRAT
	#define	CAP_RMDIR		CAP_UNLINKAT
	#define	CAP_MKFIFO		CAP_MKFIFOAT
	#define	CAP_MKNOD		CAP_MKNODAT
	#define	CAP_SOCK_ALL		(CAP_SOCK_CLIENT | CAP_SOCK_SERVER)

Sponsored by:	The FreeBSD Foundation
Reviewed by:	Christoph Mallon <christoph.mallon@gmx.de>
Many aspects discussed with:	rwatson, benl, jonathan
ABI compatibility discussed with:	kib
2013-03-02 00:53:12 +00:00
Pawel Jakub Dawidek
f4d0191b22 Reduce lock scope a little. 2013-03-01 21:57:02 +00:00
Pawel Jakub Dawidek
f0ad2ecb9c Style. 2013-02-17 11:56:36 +00:00
Pawel Jakub Dawidek
8e1d51ab40 - Require CAP_FSYNC capability right when opening a file with O_SYNC or O_FSYNC
flags.
- While here simplify check for locking flags.

Sponsored by:	The FreeBSD Foundation
2013-02-17 11:53:51 +00:00
Konstantin Belousov
2ca4998342 Stop translating the ERESTART error from the open(2) into EINTR.
Posix requires that open(2) is restartable for SA_RESTART.

For non-posix objects, in particular, devfs nodes, still disable
automatic restart of the opens. The open call to a driver could have
significant side effects for the hardware.

Noted and reviewed by:	jilles
Discussed with:	bde
MFC after:	2 weeks
2013-02-07 14:53:33 +00:00
Pawel Jakub Dawidek
4bbe7b0c20 Now that MPSAFE flag is gone, we can arrange code a bit better. 2013-01-31 22:20:05 +00:00
Pawel Jakub Dawidek
b108953c6f Remove leftover label after Giant removal from VFS. 2013-01-31 22:15:41 +00:00
Ed Schouten
d7259a57bd Remove unused `vfslocked' variable.
I have no idea what this `vfslocked' thing means. I wonder how it ended
up here.
2012-10-22 21:14:26 +00:00
Konstantin Belousov
5050aa86cf Remove the support for using non-mpsafe filesystem modules.
In particular, do not lock Giant conditionally when calling into the
filesystem module, remove the VFS_LOCK_GIANT() and related
macros. Stop handling buffers belonging to non-mpsafe filesystems.

The VFS_VERSION is bumped to indicate the interface change which does
not result in the interface signatures changes.

Conducted and reviewed by:	attilio
Tested by:	pho
2012-10-22 17:50:54 +00:00
Konstantin Belousov
36c6f3aaae Acquire the rangelock for truncate(2) as well.
Reported and reviewed by:	avg
Tested by:	pho
MFC after:	1 week
2012-10-15 18:15:18 +00:00
Pawel Jakub Dawidek
55711729f3 - Enforce CAP_MKFIFO on mkfifoat(2), not on mknodat(2). Without this change
mkfifoat(2) was not restricted.
- Introduce CAP_MKNOD and enforce it on mknodat(2).

Sponsored by:	FreeBSD Foundation
MFC after:	2 weeks
2012-10-01 05:43:24 +00:00
Pawel Jakub Dawidek
5c3e5c7f03 Require CAP_DELETE on directory descriptor for unlinkat(2).
Sponsored by:	FreeBSD Foundation
MFC after:	2 weeks
2012-09-25 21:00:36 +00:00
Pawel Jakub Dawidek
cffcbad2bf Require CAP_CREATE on directory descriptor for symlinkat(2).
Sponsored by:	FreeBSD Foundation
MFC after:	2 weeks
2012-09-25 20:59:12 +00:00
Pawel Jakub Dawidek
d2e166e654 Require CAP_CREATE on directory descriptor for linkat(2).
Sponsored by:	FreeBSD Foundation
MFC after:	2 weeks
2012-09-25 20:58:15 +00:00
Pawel Jakub Dawidek
1159429db8 O_EXEC flag is not part of the O_ACCMODE mask, check it separately.
If O_EXEC is provided don't require CAP_READ/CAP_WRITE, as O_EXEC
is mutually exclusive to O_RDONLY/O_WRONLY/O_RDWR.

Without this change CAP_FEXECVE capability right is not enforced.

Sponsored by:	FreeBSD Foundation
MFC after:	3 days
2012-09-25 20:48:49 +00:00
John Baldwin
e838f09cd0 Reorder the managament of advisory locks on open files so that the advisory
lock is obtained before the write count is increased during open() and the
lock is released after the write count is decreased during close().

The first change closes a race where an open() that will block with O_SHLOCK
or O_EXLOCK can increase the write count while it waits.  If the process
holding the current lock on the file then tries to call exec() on the file
it has locked, it can fail with ETXTBUSY even though the advisory lock is
preventing other threads from succesfully completeing a writable open().

The second change closes a race where a read-only open() with O_SHLOCK or
O_EXLOCK may return successfully while the write count is non-zero due to
another descriptor that had the advisory lock and was blocking the open()
still being in the process of closing.  If the process that completed the
open() then attempts to call exec() on the file it locked, it can fail with
ETXTBUSY even though the other process that held a write lock has closed
the file and released the lock.

Reviewed by:	kib
MFC after:	1 month
2012-07-31 18:25:00 +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
John Baldwin
cd4ecf3cd2 Further refine the implementation of POSIX_FADV_NOREUSE.
First, extend the changes in r230782 to better handle the common case
of using NOREUSE with sequential reads.  A NOREUSE file descriptor
will now track the last implicit DONTNEED request it made as a result
of a NOREUSE read.  If a subsequent NOREUSE read is adjacent to the
previous range, it will apply the DONTNEED request to the entire range
of both the previous read and the current read.  The effect is that
each read of a file accessed sequentially will apply the DONTNEED
request to the entire range that has been read.  This allows NOREUSE
to properly handle misaligned reads by flushing each buffer to cache
once it has been completely read.

Second, apply the same changes made to read(2) by r230782 and this
change to writes.  This provides much better performance in the
sequential write case as it allows writes to still be clustered.  It
also provides much better performance for misaligned writes.  It does
mean that NOREUSE will be generally ineffective for non-sequential
writes as the current implementation relies on a future NOREUSE
write's implicit DONTNEED request to flush the dirty buffer from the
current write.

MFC after:	2 weeks
2012-06-19 18:42:24 +00:00
Pawel Jakub Dawidek
7080f124d2 Now that dupfdopen() doesn't depend on finstall() being called earlier,
indx will never be -1 on error, as none of dupfdopen(), finstall() and
kern_capwrap() modifies it on error, but what is more important none of
those functions install and leave file at indx descriptor on error.

Leave an assert to prove my words.

MFC after:	1 month
2012-06-13 21:38:07 +00:00
Pawel Jakub Dawidek
3812dcd3de Allocate descriptor number in dupfdopen() itself instead of depending on
the caller using finstall().
This saves us the filedesc lock/unlock cycle, fhold()/fdrop() cycle and closes
a race between finstall() and dupfdopen().

MFC after:	1 month
2012-06-13 21:32:35 +00:00
Pawel Jakub Dawidek
7f35af0110 - Remove nfp variable that is not really needed.
- Update comment.
- Style nits.

MFC after:	1 month
2012-06-13 21:22:35 +00:00
Pawel Jakub Dawidek
c64dd3bae1 Remove duplicated code.
MFC after:	1 month
2012-06-13 21:15:01 +00:00
Pawel Jakub Dawidek
81424ab705 Add missing {.
MFC after:	1 month
2012-06-13 21:13:18 +00:00
Pawel Jakub Dawidek
85c1550d63 Style.
MFC after:	1 month
2012-06-13 21:11:58 +00:00
Pawel Jakub Dawidek
baf946221d There is no need to set td->td_retval[0] to -1 on error.
Confirmed by:	jhb
MFC after:	1 month
2012-06-13 21:10:00 +00:00
Pawel Jakub Dawidek
f3cd980557 Style fixes and simplifications.
MFC after:	1 month
2012-06-11 16:08:03 +00:00
John Baldwin
7ac1b61aac Split the second half of vn_open_cred() (after a vnode has been found via
a lookup or created via VOP_CREATE()) into a new vn_open_vnode() function
and use this function in fhopen() instead of duplicating code from
vn_open_cred() directly.

Tested by:	pho
Reviewed by:	kib
MFC after:	2 weeks
2012-06-08 18:32:09 +00:00
Gleb Kurtsou
76dcec5d09 Add kern_fhstat(), adjust sys_fhstat() to use it.
Extend kern_getdirentries() to accept uio segflag and optionally return
buffer residue.

Sponsored by:	Google Summer of Code 2011
2012-05-24 08:00:26 +00:00
Jaakko Heinonen
dd952f80bc The value of flags matching VNOVAL can't be supported. Return EOPNOTSUPP
from setfflags() in this case. This fixes the return value of
chflags(path, -1).

Discussed with:	bde
MFC after:	2 weeks
2012-04-20 10:08:30 +00:00
Peter Holm
39e77c4c50 Perform the parameter validation before assigning it to a signed int
variable. This fixes the problem seen with readdir(3) fuzzing.

Submitted by:	bde
MFC after:	1 week
2012-03-09 21:31:12 +00:00
Peter Holm
ffae9d4d7c Free up allocated memory used by posix_fadvise(2). 2012-03-08 20:34:13 +00:00
John Baldwin
b47f624183 Add KTR_VFS traces to track modifications to a vnode's writecount. 2012-03-08 20:27:20 +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
Konstantin Belousov
c480f781ea Current implementations of sync(2) and syncer vnode fsync() VOP uses
mnt_noasync counter to temporary remove MNTK_ASYNC mount option, which
is needed to guarantee a synchronous completion of the initiated i/o
before syscall or VOP return.  Global removal of MNTK_ASYNC option is
harmful because not only i/o started from corresponding thread becomes
synchronous, but all i/o is synchronous on the filesystem which is
initiated during sync(2) or syncer activity.

Instead of removing MNTK_ASYNC from mnt_kern_flag, provide a local
thread flag to disable async i/o for current thread only. Use the
opportunity to move DOINGASYNC() macro into sys/vnode.h and
consistently use it through places which tested for MNTK_ASYNC.

Some testing demonstrated 60-70% improvements in run time for the
metadata-intensive operations on async-mounted UFS volumes, but still
with great deviation due to other reasons.

Reviewed by:	mckusick
Tested by:	scottl
MFC after:	2 weeks
2012-02-06 11:04:36 +00:00
Konstantin Belousov
3ab0160340 Avoid LOR between vfs_busy() lock and covered vnode lock on quotaon().
The vfs_busy() is after covered vnode lock in the global lock order, but
since quotaon() does recursive VFS call to open quota file, we usually
end up locking covered vnode after mp is busied in sys_quotactl().

Change the interface of VFS_QUOTACTL(), requiring that mp was unbusied
by fs code, and do not try to pick up vfs_busy() reference in ufs quotaon,
esp. if vfs_busy cannot succeed due to unmount being performed.

Reported and tested by:	pho
MFC after:	1 week
2012-01-08 23:06:53 +00:00
John Baldwin
f427c78b19 Fire a kevent if necessary after seeking on a regular file. This fixes a
case where a kevent would not fire on a regular file if an application read
to EOF and then seeked backwards into the file.

Reviewed by:	kib
MFC after:	2 weeks
2011-12-16 20:10:00 +00:00
Eitan Adler
3eb9ab5255 Document a large number of currently undocumented sysctls. While here
fix some style(9) issues and reduce redundancy.

PR:		kern/155491
PR:		kern/155490
PR:		kern/155489
Submitted by:	Galimov Albert <wtfcrap@mail.ru>
Approved by:	bde
Reviewed by:	jhb
MFC after:	1 week
2011-12-13 00:38:50 +00:00
Konstantin Belousov
561984be06 Fix a race between getvnode() dereferencing half-constructed file
and dupfdopen().

Reported and tested by:	pho
MFC after:	3 days
2011-11-24 20:34:06 +00:00
Ed Schouten
d3a993d46b Improve *access*() parameter name consistency.
The current code mixes the use of `flags' and `mode'. This is a bit
confusing, since the faccessat() function as a `flag' parameter to store
the AT_ flag.

Make this less confusing by using the same name as used in the POSIX
specification -- `amode'.
2011-11-19 06:35:15 +00:00
John Baldwin
7edec6214e - Split out a kern_posix_fadvise() from the posix_fadvise() system call so
it can be used by in-kernel consumers.
- Make kern_posix_fallocate() public.
- Use kern_posix_fadvise() and kern_posix_fallocate() to implement the
  freebsd32 wrappers for the two system calls.
2011-11-14 18:00:15 +00:00
John Baldwin
936c09ac0f Add the posix_fadvise(2) system call. It is somewhat similar to
madvise(2) except that it operates on a file descriptor instead of a
memory region.  It is currently only supported on regular files.

Just as with madvise(2), the advice given to posix_fadvise(2) can be
divided into two types.  The first type provide hints about data access
patterns and are used in the file read and write routines to modify the
I/O flags passed down to VOP_READ() and VOP_WRITE().  These modes are
thus filesystem independent.  Note that to ease implementation (and
since this API is only advisory anyway), only a single non-normal
range is allowed per file descriptor.

The second type of hints are used to hint to the OS that data will or
will not be used.  These hints are implemented via a new VOP_ADVISE().
A default implementation is provided which does nothing for the WILLNEED
request and attempts to move any clean pages to the cache page queue for
the DONTNEED request.  This latter case required two other changes.
First, a new V_CLEANONLY flag was added to vinvalbuf().  This requests
vinvalbuf() to only flush clean buffers for the vnode from the buffer
cache and to not remove any backing pages from the vnode.  This is
used to ensure clean pages are not wired into the buffer cache before
attempting to move them to the cache page queue.  The second change adds
a new vm_object_page_cache() method.  This method is somewhat similar to
vm_object_page_remove() except that instead of freeing each page in the
specified range, it attempts to move clean pages to the cache queue if
possible.

To preserve the ABI of struct file, the f_cdevpriv pointer is now reused
in a union to point to the currently active advice region if one is
present for regular files.

Reviewed by:	jilles, kib, arch@
Approved by:	re (kib)
MFC after:	1 month
2011-11-04 04:02:50 +00:00
Kip Macy
8451d0dd78 In order to maximize the re-usability of kernel code in user space this
patch modifies makesyscalls.sh to prefix all of the non-compatibility
calls (e.g. not linux_, freebsd32_) with sys_ and updates the kernel
entry points and all places in the code that use them. It also
fixes an additional name space collision between the kernel function
psignal and the libc function of the same name by renaming the kernel
psignal kern_psignal(). By introducing this change now we will ease future
MFCs that change syscalls.

Reviewed by:	rwatson
Approved by:	re (bz)
2011-09-16 13:58:51 +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
Robert Watson
fd9a5f73f6 When falloc() was broken into separate falloc_noinstall() and finstall(),
a bug was introduced in kern_openat() such that the error from the vnode
open operation was overwritten before it was passed as an argument to
dupfdopen().  This broke operations on /dev/{stdin,stdout,stderr}.  Fix
by preserving the original error number across finstall() so that it is
still available.

Approved by:	re (kib)
Reported by:	cognet
2011-08-13 16:03:40 +00:00
Jonathan Anderson
69d377fe1b Allow Capsicum capabilities to delegate constrained
access to file system subtrees to sandboxed processes.

- Use of absolute paths and '..' are limited in capability mode.
- Use of absolute paths and '..' are limited when looking up relative
  to a capability.
- When a name lookup is performed, identify what operation is to be
  performed (such as CAP_MKDIR) as well as check for CAP_LOOKUP.

With these constraints, openat() and friends are now safe in capability
mode, and can then be used by code such as the capability-mode runtime
linker.

Approved by: re (bz), mentor (rwatson)
Sponsored by: Google Inc
2011-08-13 09:21:16 +00:00
Jonathan Anderson
d6d2cfa24b Only call fdclose() on successfully-opened FDs.
Since kern_openat() now uses falloc_noinstall() and finstall() separately,
there are cases where we could get to cleanup code without ever creating
a file descriptor. In those cases, we should not call fdclose() on FD -1.

Approved by: re (kib), mentor (rwatson)
Sponsored by: Google Inc
2011-08-11 13:29:59 +00:00
Robert Watson
a9d2f8d84f Second-to-last commit implementing Capsicum capabilities in the FreeBSD
kernel for FreeBSD 9.0:

Add a new capability mask argument to fget(9) and friends, allowing system
call code to declare what capabilities are required when an integer file
descriptor is converted into an in-kernel struct file *.  With options
CAPABILITIES compiled into the kernel, this enforces capability
protection; without, this change is effectively a no-op.

Some cases require special handling, such as mmap(2), which must preserve
information about the maximum rights at the time of mapping in the memory
map so that they can later be enforced in mprotect(2) -- this is done by
narrowing the rights in the existing max_protection field used for similar
purposes with file permissions.

In namei(9), we assert that the code is not reached from within capability
mode, as we're not yet ready to enforce namespace capabilities there.
This will follow in a later commit.

Update two capability names: CAP_EVENT and CAP_KEVENT become
CAP_POST_KEVENT and CAP_POLL_KEVENT to more accurately indicate what they
represent.

Approved by:	re (bz)
Submitted by:	jonathan
Sponsored by:	Google Inc
2011-08-11 12:30:23 +00:00
Rick Macklem
694a586a43 Add a lock flags argument to the VFS_FHTOVP() file system
method, so that callers can indicate the minimum vnode
locking requirement. This will allow some file systems to choose
to return a LK_SHARED locked vnode when LK_SHARED is specified
for the flags argument. This patch only adds the flag. It
does not change any file system to use it and all callers
specify LK_EXCLUSIVE, so file system semantics are not changed.

Reviewed by:	kib
2011-05-22 01:07:54 +00:00
Matthew D Fleming
1ce4508f6d Allow VOP_ALLOCATE to be iterative, and have kern_posix_fallocate(9)
drive looping and potentially yielding.

Requested by:	kib
2011-04-19 16:36:24 +00:00
Matthew D Fleming
5d253e418f Fix a copy/paste whitespace error. 2011-04-18 16:40:47 +00:00
Matthew D Fleming
d91f88f7f3 Add the posix_fallocate(2) syscall. The default implementation in
vop_stdallocate() is filesystem agnostic and will run as slow as a
read/write loop in userspace; however, it serves to correctly
implement the functionality for filesystems that do not implement a
VOP_ALLOCATE.

Note that __FreeBSD_version was already bumped today to 900036 for any
ports which would like to use this function.

Also reserve space in the syscall table for posix_fadvise(2).

Reviewed by:	-arch (previous version)
2011-04-18 16:32:22 +00:00
Konstantin Belousov
1fe80828e7 After the r219999 is merged to stable/8, rename fallocf(9) to falloc(9)
and remove the falloc() version that lacks flag argument. This is done
to reduce the KPI bloat.

Requested by:	jhb
X-MFC-note:	do not
2011-04-01 13:28:34 +00:00
Konstantin Belousov
7332c129e0 Add support for executing the FreeBSD 1/i386 a.out binaries on amd64.
In particular:
- implement compat shims for old stat(2) variants and ogetdirentries(2);
- implement delivery of signals with ancient stack frame layout and
  corresponding sigreturn(2);
- implement old getpagesize(2);
- provide a user-mode trampoline and LDT call gate for lcall $7,$0;
- port a.out image activator and connect it to the build as a module
  on amd64.

The changes are hidden under COMPAT_43.

MFC after:   1 month
2011-04-01 11:16:29 +00:00
Konstantin Belousov
246d35ec91 Add O_CLOEXEC flag to open(2) and fhopen(2).
The new function fallocf(9), that is renamed falloc(9) with added
flag argument, is provided to facilitate the merge to stable branch.

Reviewed by:	jhb
MFC after:	1 week
2011-03-25 14:00:36 +00:00
Rui Paulo
79856499bd Add an extra comment to the SDT probes definition. This allows us to get
use '-' in probe names, matching the probe names in Solaris.[1]

Add userland SDT probes definitions to sys/sdt.h.

Sponsored by:	The FreeBSD Foundation
Discussed with:	rwaston [1]
2010-08-22 11:18:57 +00:00
Konstantin Belousov
aa81ae08e9 In revoke(), verify that VCHR vnode indeed belongs to devfs.
Found and tested by:	pho
MFC after:	1 week
2010-07-06 18:20:49 +00:00
Konstantin Belousov
d5ff273563 Handle a case in kern_openat() when vn_open() change file type from
DTYPE_VNODE.

Only acquire locks for O_EXLOCK/O_SHLOCK if file type is still vnode,
since we allow for fcntl(2) to process with advisory locks for
DTYPE_VNODE only. Another reason is that all fo_close() routines need to
check and release locks otherwise.

For O_TRUNC, call fo_truncate() instead of truncating the vnode.

Discussed with:	rwatson
MFC after:	2 week
2010-04-13 08:52:20 +00:00
Konstantin Belousov
5478ba7358 Remove XXX comment. Add another comment, describing why f_vnode assignment
is useful.

MFC after:	3 days
2010-04-13 08:45:55 +00:00
Ed Schouten
510ea843ba Rename st_*timespec fields to st_*tim for POSIX 2008 compliance.
A nice thing about POSIX 2008 is that it finally standardizes a way to
obtain file access/modification/change times in sub-second precision,
namely using struct timespec, which we already have for a very long
time. Unfortunately POSIX uses different names.

This commit adds compatibility macros, so existing code should still
build properly. Also change all source code in the kernel to work
without any of the compatibility macros. This makes it all a less
ambiguous.

I am also renaming st_birthtime to st_birthtim, even though it was a
local extension anyway. It seems Cygwin also has a st_birthtim.
2010-03-28 13:13:22 +00:00
Ed Schouten
0fef797f4a Actually make O_DIRECTORY work.
According to POSIX open() must return ENOTDIR when the path name does
not refer to a path name. Change vn_open() to respect this flag. This
also simplifies the Linuxolator a bit.
2010-03-21 20:43:23 +00:00
John Baldwin
9e0cda0391 Fix a comment nit.
Submitted by:	Alexander Best
2010-03-11 13:16:06 +00:00
John Baldwin
ab99e589dd Allow lseek(SEEK_END) to work on disk devices by using the DIOCGMEDIASIZE
to determine the media size.

Submitted by:	nox
MFC after:	1 week
2010-03-03 16:18:04 +00:00
Robert Watson
6c77113c9f Remove stale comment about socket buffer accounting from access(2) code.
It is the case, however, that the uidinfo of the temporary credential
set up for access(2) is not properly updated when its effective uid is
changed.

MFC after:	3 days
2010-02-27 19:57:40 +00:00
Kirk McKusick
e268f54cb4 Background:
When renaming a directory it passes through several intermediate
states. First its new name will be created causing it to have two
names (from possibly different parents). Next, if it has different
parents, its value of ".." will be changed from pointing to the old
parent to pointing to the new parent. Concurrently, its old name
will be removed bringing it back into a consistent state. When fsck
encounters an extra name for a directory, it offers to remove the
"extraneous hard link"; when it finds that the names have been
changed but the update to ".." has not happened, it offers to rewrite
".." to point at the correct parent. Both of these changes were
considered unexpected so would cause fsck in preen mode or fsck in
background mode to fail with the need to run fsck manually to fix
these problems. Fsck running in preen mode or background mode now
corrects these expected inconsistencies that arise during directory
rename. The functionality added with this update is used by fsck
running in background mode to make these fixes.

Solution:

This update adds three new fsck sysctl commands to support background
fsck in correcting expected inconsistencies that arise from incomplete
directory rename operations. They are:

setcwd(dirinode) - set the current directory to dirinode in the
    filesystem associated with the snapshot.
setdotdot(oldvalue, newvalue) - Verify that the inode number for ".."
    in the current directory is oldvalue then change it to newvalue.
unlink(nameptr, oldvalue) - Verify that the inode number associated
    with nameptr in the current directory is oldvalue then unlink it.

As with all other fsck sysctls, these new ones may only be used by
processes with appropriate priviledge.

Reported by:    	jeff
Security issues:	rwatson
2010-01-11 20:44:05 +00:00
Edward Tomasz Napierala
9d7031a6d6 Don't add VAPPEND if the file is not being opened for writing. Note that this
only affects cases where open(2) is being used improperly - i.e. when the user
specifies O_APPEND without O_WRONLY or O_RDWR.

Reviewed by:	rwatson
2009-12-08 20:47:10 +00:00
Konstantin Belousov
db17314ea4 In fhopen, vfs_ref() the mount point while vnode is unlocked, to prevent
vn_start_write(NULL, &mp) from operating on potentially freed or reused
struct mount *.

Remove unmatched vfs_rel() in cleanup.

Noted and reviewed by:	tegge
Tested by:	pho
MFC after:	3 days
2009-09-06 11:44:46 +00:00
Konstantin Belousov
4f4946d337 Honor the vfs.timestamp_precision sysctl settings for utimes(path, NULL)
and similar calls.

Obtained from:	Petr Salinger, Debian GNU/kFreeBSD, Debian bug #489894
MFC after:	3 days
2009-08-26 14:32:37 +00:00
John Baldwin
87eca70e0c Fix some LORs between vnode locks and filedescriptor table locks.
- Don't grab the filedesc lock just to read fd_cmask.
- Drop vnode locks earlier when mounting the root filesystem and before
  sanitizing stdin/out/err file descriptors during execve().

Submitted by:	kib
Approved by:	re (rwatson)
MFC after:	1 week
2009-07-31 13:40:06 +00:00
Robert Watson
b146fc1bf0 Rework vnode argument auditing to follow the same structure, in order
to avoid exposing ARG_ macros/flag values outside of the audit code in
order to name which one of two possible vnodes will be audited for a
system call.

Approved by:	re (kib)
Obtained from:	TrustedBSD Project
MFC after:	1 month
2009-07-28 21:52:24 +00:00
Edward Tomasz Napierala
c38898116a There is an optimization in chmod(1), that makes it not to call chmod(2)
if the new file mode is the same as it was before; however, this
optimization must be disabled for filesystems that support NFSv4 ACLs.
Chmod uses pathconf(2) to determine whether this is the case - however,
pathconf(2) always follows symbolic links, while the 'chmod -h' doesn't.

This change adds lpathconf(3) to make it possible to solve that problem
in a clean way.

Reviewed by:	rwatson (earlier version)
Approved by:	re (kib)
2009-07-08 15:23:18 +00:00
Robert Watson
03f7b00438 For access(2) and eaccess(2), audit the requested access mode.
Approved by:	re (audit argument blanket)
MFC after:	3 days
2009-07-01 22:47:45 +00:00
Robert Watson
422d786676 Audit the file descriptor number passed to lseek(2).
Approved by:	re (kib)
MFC after:	3 days
2009-07-01 15:37:23 +00:00
Robert Watson
c5957d6bba Fix link(2) auditing: use the second audit record path for the new object
name.

Approved by:	re (kib)
MFC after:	3 days
2009-07-01 13:22:08 +00:00
Robert Watson
14961ba789 Replace AUDIT_ARG() with variable argument macros with a set more more
specific macros for each audit argument type.  This makes it easier to
follow call-graphs, especially for automated analysis tools (such as
fxr).

In MFC, we should leave the existing AUDIT_ARG() macros as they may be
used by third-party kernel modules.

Suggested by:	brooks
Approved by:	re (kib)
Obtained from:	TrustedBSD Project
MFC after:	1 week
2009-06-27 13:58:44 +00:00
Bjoern A. Zeeb
aed2a06174 Remove the static from int hardlink_check_uid.
There is an external use in the opensolaris code.

I am not sure how this ever worked but I have seen two reports of:
	link_elf: symbol hardlink_check_uid undefined
lately.

Reported by:	Scott Ullrich (sullrich gmail.com), pfsense
Reported by:	Mister Olli (mister.olli googlemail.com)
2009-06-13 13:09:20 +00:00
Paul Saab
27bfb741a0 Simply shared vnode locking and extend it to also include fsync.
Also, in vop_write, no longer assert for exclusive locks on the
vnode.

Reviewed by:	jhb, kmacy, jeffr
2009-06-08 21:23:54 +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
Jamie Gritton
0304c73163 Add hierarchical jails. A jail may further virtualize its environment
by creating a child jail, which is visible to that jail and to any
parent jails.  Child jails may be restricted more than their parents,
but never less.  Jail names reflect this hierarchy, being MIB-style
dot-separated strings.

Every thread now points to a jail, the default being prison0, which
contains information about the physical system.  Prison0's root
directory is the same as rootvnode; its hostname is the same as the
global hostname, and its securelevel replaces the global securelevel.
Note that the variable "securelevel" has actually gone away, which
should not cause any problems for code that properly uses
securelevel_gt() and securelevel_ge().

Some jail-related permissions that were kept in global variables and
set via sysctls are now per-jail settings.  The sysctls still exist for
backward compatibility, used only by the now-deprecated jail(2) system
call.

Approved by:	bz (mentor)
2009-05-27 14:11:23 +00:00
Jeff Roberson
bf422e5f27 - Implement a lockless file descriptor lookup algorithm in
fget_unlocked().
 - Save old file descriptor tables created on expansion until
   the entire descriptor table is freed so that pointers may be
   followed without regard for expanders.
 - Mark the file zone as NOFREE so we may attempt to reference
   potentially freed files.
 - Convert several fget_locked() users to fget_unlocked().  This
   requires us to manage reference counts explicitly but reduces
   locking overhead in the common case.
2009-05-14 03:24:22 +00:00
Konstantin Belousov
3b616faed5 Prevent overflow of uio_resid.
Noted by:	jhb
MFC after:	3 days
2009-05-11 19:58:03 +00:00
Attilio Rao
dfd233edd5 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
Robert Watson
885868cd8f Remove VOP_LEASE and supporting functions. This hasn't been used since
the removal of NQNFS, but was left in in case it was required for NFSv4.
Since our new NFSv4 client and server can't use it for their
requirements, GC the old mechanism, as well as other unused lease-
related code and interfaces.

Due to its impact on kernel programming and binary interfaces, this
change should not be MFC'd.

Proposed by:    jeff
Reviewed by:    jeff
Discussed with: rmacklem, zach loafman @ isilon
2009-04-10 10:52:19 +00:00
Ed Schouten
0eee862a54 Don't make Linux stat() open character devices to resolve its name.
The existing code calls kern_open() to resolve the vnode of a pathname
right after a stat(). This is not correct, because it causes random
character devices to be opened in /dev. This means ls'ing a tape
streamer will cause it to rewind, for example. Changes I have made:

- Add kern_statat_vnhook() to allow binary emulators to `post-process'
  struct stat, using the proper vnode.

- Remove unneeded printf's from stat() and statfs().

- Make the Linuxolator use kern_statat_vnhook(), replacing
  translate_path_major_minor_at().

- Let translate_fd_major_minor() use vp->v_rdev instead of
  vp->v_un.vu_cdev.

Result:

	crw-rw-rw- 1 root root   0, 14 Feb 20 13:54 /dev/ptmx
	crw--w---- 1 root adm  136,  0 Feb 20 14:03 /dev/pts/0
	crw--w---- 1 root adm  136,  1 Feb 20 14:02 /dev/pts/1
	crw--w---- 1 ed   tty  136,  2 Feb 20 14:03 /dev/pts/2

Before this commit, ptmx also had a major number of 136, because it
silently allocated and deallocated a pseudo-terminal. Device nodes that
cannot be opened now have proper major/minor-numbers.

Reviewed by:	kib, netchild, rdivacky (thanks!)
2009-02-20 13:05:29 +00:00
John Baldwin
ea77ff0a15 Use shared vnode locks when invoking VOP_READDIR().
MFC after:	1 month
2009-02-13 18:18:14 +00:00
Edward Tomasz Napierala
27dd8057d3 In some situations, mnt_lockref could go negative due to vfs_unbusy() being
called without calling vfs_busy() first.  This made umount(8) hang waiting
for mnt_lockref to become zero, which would never happen.

Reviewed by:	kib
Approved by:	rwatson (mentor)
Reported by:	pho
Found with:	stress2
Sponsored by:	FreeBSD Foundation
2009-02-05 08:46:18 +00:00
John Baldwin
efc65197a1 Use shared vnode locks for fchdir().
Submitted by:	ups
2009-01-23 22:13:30 +00:00
Peter Holm
ab62a2d023 Prevent overflow of uio_resid.
Approved by:	kib
2008-12-27 10:13:43 +00:00
Konstantin Belousov
548066ea66 The quotactl, statfs and fstatfs syscall implementations may dereference
NULL pointer to struct mount if the looked up vnode is reclaimed. Also,
these syscalls only mnt_ref() the mp, still allowing it to be unmounted;
only struct mount memory is kept from being reused.

Lock the vnode when doing name lookup, then reference its mount point,
unlock the vnode and vfs_busy the mountpoint. This sequence shall take
care of both races.

Reported and tested by:	pho
Discussed with:	attilio
MFC after:	1 month
2008-12-18 12:01:19 +00:00
Konstantin Belousov
6179164448 In the nfsrv_fhtovp(), after the vfs_getvfs() function found the pointer
to the fs, but before a vnode on the fs is locked, unmount may free fs
structures, causing access to destroyed data and freed memory.

Introduce a vfs_busymp() function that looks up and busies found
fs while mountlist_mtx is held. Use it in nfsrv_fhtovp() and in the
implementation of the handle syscalls.

Two other uses of the vfs_getvfs() in the vfs_subr.c, namely in
sysctl_vfs_ctl and vfs_getnewfsid seems to be ok. In particular,
sysctl_vfs_ctl is protected by Giant by being a non-sleeping sysctl
handler, that prevents Giant-locked unmount code to interfere with it.

Noted by:	tegge
Reviewed by:	dfr
Tested by:	pho
MFC after:	1 month
2008-11-29 13:34:59 +00:00
Craig Rodrigues
e506f34b24 Merge latest DTrace changes from Perforce.
Approved by:	jb
2008-11-05 19:40:36 +00:00
John Baldwin
927edcc9ba Use shared vnode locks for auditing vnode arguments as auditing only
does a VOP_GETATTR() which does not require an exclusive lock.

Reviewed by:	csjp, rwatson
2008-11-04 22:31:04 +00:00
John Baldwin
21fc02d271 Use shared vnode locks instead of exclusive vnode locks for the access(),
chdir(), chroot(), eaccess(), fpathconf(), fstat(), fstatfs(), lseek()
(when figuring out the current size of the file in the SEEK_END case),
pathconf(), readlink(), and statfs() system calls.

Submitted by:	ups (mostly)
Tested by:	pho
MFC after:	1 month
2008-11-03 20:31:00 +00:00
Attilio Rao
83b3bdbc8a Improve VFS locking:
- Implement real draining for vfs consumers by not relying on the
  mnt_lock and using instead a refcount in order to keep track of lock
  requesters.
- Due to the change above, remove the mnt_lock lockmgr because it is now
  useless.
- Due to the change above, vfs_busy() is no more linked to a lockmgr.
  Change so its KPI by removing the interlock argument and defining 2 new
  flags for it: MBF_NOWAIT which basically replaces the LK_NOWAIT of the
  old version (which was unlinked from the lockmgr alredy) and
  MBF_MNTLSTLOCK which provides the ability to drop the mountlist_mtx
  once the mnt interlock is held (ability still desired by most consumers).
- The stub used into vfs_mount_destroy(), that allows to override the
  mnt_ref if running for more than 3 seconds, make it totally useless.
  Remove it as it was thought to work into older versions.
  If a problem of "refcount held never going away" should appear, we will
  need to fix properly instead than trust on such hackish solution.
- Fix a bug where returning (with an error) from dounmount() was still
  leaving the MNTK_MWAIT flag on even if it the waiters were actually
  woken up. Just a place in vfs_mount_destroy() is left because it is
  going to recycle the structure in any case, so it doesn't matter.
- Remove the markercnt refcount as it is useless.

This patch modifies VFS ABI and breaks KPI for vfs_busy() so manpages and
__FreeBSD_version will be modified accordingly.

Discussed with:	kib
Tested by:	pho
2008-11-02 10:15:42 +00:00
Edward Tomasz Napierala
15bc6b2bd8 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
John Baldwin
6239752624 Whitespace fix. 2008-10-23 21:50:16 +00:00
Dag-Erling Smørgrav
1ede983cc9 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
John Baldwin
63f8fe9e8b Split the copyout of *base at the end of getdirentries() out leaving the
rest in kern_getdirentries().  Use kern_getdirentries() to implement
freebsd32_getdirentries().  This fixes a bug where calls to getdirentries()
in 32-bit binaries would trash the 4 bytes after the 'long base' in
userland.

Submitted by:	ups
MFC after:	1 week
2008-10-22 21:55:48 +00:00
Pawel Jakub Dawidek
2765482b7f When setting error to EINVAL in 'fvp == tdvp' case, jump to out label,
because if not, the error will be later overwritten by
mac_vnode_check_rename_to() call.

Reviewed by:	rwatson
2008-09-01 10:11:39 +00:00
Attilio Rao
59d4932531 Decontextualize vfs_busy(), vfs_unbusy() and vfs_mount_alloc() functions.
Manpages are updated accordingly.

Tested by:	Diego Sardina <siarodx at gmail dot com>
2008-08-31 14:26:08 +00:00
Attilio Rao
0359a12ead 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
Robert Watson
3319d71265 If S_IFIFO is passed to mknod(2), invoke kern_mkfifoat(9) to create a
FIFO, as required by SUSv3.  No specific privilege check is performed
in this case, as FIFOs may be created by unprivileged processes
(subject to the normal file system name space restrictions that may be
in place).

Unlike the Apple implementation, we reject requests to create a FIFO
using mknod(2) if there is a non-zero dev argument to the system call,
which is permitted by the Open Group specification ("... undefined
...").  We might want to revise this if we find it causes
compatibility problems for applications in practice.

PR:		kern/74242, kern/68459
Obtained from:	Apple, Inc.
MFC after:	3 weeks
2008-06-22 21:51:32 +00:00
Don Lewis
8a3724388b vfs_syscalls.c 1.452 mistakenly swapped the behavior of chown() and lchown(). 2008-04-07 00:29:32 +00:00
Konstantin Belousov
e4193f25cb Implement the
openat(2), faccessat(2), fchmodat(2), fchownat(2), fstatat(2),
	futimesat(2), linkat(2), mkdirat(2), mkfifoat(2), mknodat(2),
	readlinkat(2), renameat(2), symlinkat(2)
syscalls.

Based on the submission by rdivacky,
	sponsored by Google Summer of Code 2007
Reviewed by:	rwatson, rdivacky
Tested by:	pho
2008-03-31 12:04:20 +00:00
Konstantin Belousov
e314f69fff Add the support for the O_EXEC open(2) mode, as specified by the
POSIX Extended API Set Part 2 extension specification.

Reviewed by:	rwatson, rdivacky
Tested by:	pho
2008-03-31 11:57:18 +00:00
Dag-Erling Smørgrav
60e15db992 This patch adds a new ktrace(2) record type, KTR_STRUCT, whose payload
consists of the null-terminated name and the contents of any structure
you wish to record.  A new ktrstruct() function constructs and emits a
KTR_STRUCT record.  It is accompanied by convenience macros for struct
stat and struct sockaddr.

In kdump(1), KTR_STRUCT records are handled by a dispatcher function
that runs stringent sanity checks on its contents before handing it
over to individual decoding funtions for each type of structure.
Currently supported structures are struct stat and struct sockaddr for
the AF_INET, AF_INET6 and AF_UNIX families; support for AF_APPLETALK
and AF_IPX is present but disabled, as I am unable to test it properly.

Since 's' was already taken, the letter 't' is used by ktrace(1) to
enable KTR_STRUCT trace points, and in kdump(1) to enable their
decoding.

Derived from patches by Andrew Li <andrew2.li@citi.com>.

PR:		kern/117836
MFC after:	3 weeks
2008-02-23 01:01:49 +00:00
Ruslan Ermilov
5f56182b6f Change readlink(2)'s return type and type of the last argument
to match POSIX.

Prodded by:	Alexey Lyashkov
2008-02-12 20:09:04 +00:00
Attilio Rao
22db15c06f 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 Rao
cb05b60a89 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
John Baldwin
e46502943a Make ftruncate a 'struct file' operation rather than a vnode operation.
This makes it possible to support ftruncate() on non-vnode file types in
the future.
- 'struct fileops' grows a 'fo_truncate' method to handle an ftruncate() on
  a given file descriptor.
- ftruncate() moves to kern/sys_generic.c and now just fetches a file
  object and invokes fo_truncate().
- The vnode-specific portions of ftruncate() move to vn_truncate() in
  vfs_vnops.c which implements fo_truncate() for vnode file types.
- Non-vnode file types return EINVAL in their fo_truncate() method.

Submitted by:	rwatson
2008-01-07 20:05:19 +00:00
Jeff Roberson
397c19d175 Remove explicit locking of struct file.
- Introduce a finit() which is used to initailize the fields of struct file
   in such a way that the ops vector is only valid after the data, type,
   and flags are valid.
 - Protect f_flag and f_count with atomic operations.
 - Remove the global list of all files and associated accounting.
 - Rewrite the unp garbage collection such that it no longer requires
   the global list of all files and instead uses a list of all unp sockets.
 - Mark sockets in the accept queue so we don't incorrectly gc them.

Tested by:	kris, pho
2007-12-30 01:42:15 +00:00
Robert Watson
30d239bc4c 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
Robert Watson
45e0f3d63d Rename mac_check_vnode_delete() MAC Framework and MAC Policy entry
point to mac_check_vnode_unlink(), reflecting UNIX naming conventions.

This is the first of several commits to synchronize the MAC Framework
in FreeBSD 7.0 with the MAC Framework as it will appear in Mac OS X
Leopard.

Reveiwed by:    csjp, Samy Bahra <sbahra at gwu dot edu>
Submitted by:   Jacques Vidrine <nectar at apple dot com>
Obtained from:  Apple Computer, Inc.
Sponsored by:   SPARTA, SPAWAR
Approved by:    re (bmah)
2007-09-10 00:00:18 +00:00
John Baldwin
cc479dda4a Rework the routines to convert a 5.x+ statfs structure (with fixed-size
64-bit counters) to a 4.x statfs structure (with long-sized counters).
- For block counters, we scale up the block size sufficiently large so
  that the resulting block counts fit into a the long-sized (long for the
  ABI, so 32-bit in freebsd32) counters.  In 4.x the NFS client's statfs
  VOP did this already.  This can lie about the block size to 4.x binaries,
  but it presents a more accurate picture of the ratios of free and
  available space.
- For non-block counters, fix the freebsd32 stats converter to cap the
  values at INT32_MAX rather than losing the upper 32-bits to match the
  behavior of the 4.x statfs conversion routine in vfs_syscalls.c

Approved by:	re (kensmith)
2007-08-28 20:28:12 +00:00
Peter Wemm
c2815ad564 Add freebsd6_ wrappers for mmap/lseek/pread/pwrite/truncate/ftruncate
Approved by: re (kensmith)
2007-07-04 22:57:21 +00:00
Robert Watson
32f9753cfb Eliminate now-unused SUSER_ALLOWJAIL arguments to priv_check_cred(); in
some cases, move to priv_check() if it was an operation on a thread and
no other flags were present.

Eliminate caller-side jail exception checking (also now-unused); jail
privilege exception code now goes solely in kern_jail.c.

We can't yet eliminate suser() due to some cases in the KAME code where
a privilege check is performed and then used in many different deferred
paths.  Do, however, move those prototypes to priv.h.

Reviewed by:	csjp
Obtained from:	TrustedBSD Project
2007-06-12 00:12:01 +00:00
Konstantin Belousov
9e223287c0 Revert UF_OPENING workaround for CURRENT.
Change the VOP_OPEN(), vn_open() vnode operation and d_fdopen() cdev operation
argument from being file descriptor index into the pointer to struct file.

Proposed and reviewed by:	jhb
Reviewed by:	daichi (unionfs)
Approved by:	re (kensmith)
2007-05-31 11:51:53 +00:00
Konstantin Belousov
5c76452f8f Mark the filedescriptor table entries with VOP_OPEN being performed for them
as UF_OPENING. Disable closing of that entries. This should fix the crashes
caused by devfs_open() (and fifo_open()) dereferencing struct file * by
index, while the filedescriptor is closed by parallel thread.

Idea by:	tegge
Reviewed by:	tegge (previous version of patch)
Tested by:	Peter Holm
Approved by:	re (kensmith)
MFC after:	3 weeks
2007-05-04 14:23:29 +00:00
Pawel Jakub Dawidek
f6521d1c31 Implement SEEK_DATA and SEEK_HOLE extensions to lseek(2) as found in
OpenSolaris. For more information please refer to:

	http://blogs.sun.com/bonwick/entry/seek_hole_and_seek_data
2007-04-05 21:10:53 +00:00
Robert Watson
5e3f7694b1 Replace custom file descriptor array sleep lock constructed using a mutex
and flags with an sxlock.  This leads to a significant and measurable
performance improvement as a result of access to shared locking for
frequent lookup operations, reduced general overhead, and reduced overhead
in the event of contention.  All of these are imported for threaded
applications where simultaneous access to a shared file descriptor array
occurs frequently.  Kris has reported 2x-4x transaction rate improvements
on 8-core MySQL benchmarks; smaller improvements can be expected for many
workloads as a result of reduced overhead.

- Generally eliminate the distinction between "fast" and regular
  acquisisition of the filedesc lock; the plan is that they will now all
  be fast.  Change all locking instances to either shared or exclusive
  locks.

- Correct a bug (pointed out by kib) in fdfree() where previously msleep()
  was called without the mutex held; sx_sleep() is now always called with
  the sxlock held exclusively.

- Universally hold the struct file lock over changes to struct file,
  rather than the filedesc lock or no lock.  Always update the f_ops
  field last. A further memory barrier is required here in the future
  (discussed with jhb).

- Improve locking and reference management in linux_at(), which fails to
  properly acquire vnode references before using vnode pointers.  Annotate
  improper use of vn_fullpath(), which will be replaced at a future date.

In fcntl(), we conservatively acquire an exclusive lock, even though in
some cases a shared lock may be sufficient, which should be revisited.
The dropping of the filedesc lock in fdgrowtable() is no longer required
as the sxlock can be held over the sleep operation; we should consider
removing that (pointed out by attilio).

Tested by:	kris
Discussed with:	jhb, kris, attilio, jeff
2007-04-04 09:11:34 +00:00
John Baldwin
ebb3c22c16 Don't go to a whole lot of extra work to handle the race where the new
file descriptor is closed out from under us in kern_open().  This race
is already handled and the file will be closed when kern_open() does an
fdrop just before returning.
2007-04-02 13:40:38 +00:00
John Baldwin
ecd8246189 If vn_open() fails during kern_open(), don't fdrop() the new file object
until after the call to fdclose().  This closes an obscure race that
could result in the later call to fdclose() actually closing a different
file descriptor if another thread close()'s the file descriptor being
opened before fdrop() is called, so the fdrop() in kern_open() frees the
file object, then the second thread (or a third) creates a new file
descriptor which reuses both the same index and the same file pointer
thus tricking fdclose() in the first thread into thinking that the
original file was still open.

MFC after:	1 week
2007-03-21 19:32:08 +00:00
Konstantin Belousov
71d49316cc Busy filesystem around call of VFS_QUOTACTL() vfs op.
Tested by:	Peter Holm
Reviewed by:	tegge
Approved by:	re (kensmith)
2007-03-14 08:45:55 +00:00
Robert Watson
873fbcd776 Further system call comment cleanup:
- Remove also "MP SAFE" after prior "MPSAFE" pass. (suggested by bde)
- Remove extra blank lines in some cases.
- Add extra blank lines in some cases.
- Remove no-op comments consisting solely of the function name, the word
  "syscall", or the system call name.
- Add punctuation.
- Re-wrap some comments.
2007-03-05 13:10:58 +00:00
Konstantin Belousov
9b2f1a0740 Remove union_dircheckp hook, it is not needed by new unionfs code anymore.
As consequence, getdirentries() no longer needs to drop/reacquire
directory vnode lock, that would allow it to be reclaimed in between.

Reported and tested by:	Peter Holm
Approved by:		rodrigc (unionfs)
MFC after:		1 week
2007-02-19 10:56:09 +00:00
Pawel Jakub Dawidek
10bcafe9ab Move vnode-to-file-handle translation from vfs_vptofh to vop_vptofh method.
This way we may support multiple structures in v_data vnode field within
one file system without using black magic.

Vnode-to-file-handle should be VOP in the first place, but was made VFS
operation to keep interface as compatible as possible with SUN's VFS.
BTW. Now Solaris also implements vnode-to-file-handle as VOP operation.

VFS_VPTOFH() was left for API backward compatibility, but is marked for
removal before 8.0-RELEASE.

Approved by:	mckusick
Discussed with:	many (on IRC)
Tested with:	ufs, msdosfs, cd9660, nullfs and zfs
2007-02-15 22:08:35 +00:00
Robert Watson
168d0553a3 Following a repo-copy of vfs_syscalls.c to vfs_extattr.c, remove
non-extattr functions from vfs_extattr.c, and extattr functions from
vfs_syscalls.c.

Change copyright/license on vfs_extattr.c to my copyright/license on
the extended attribute implementation (from extattr.h).

Clean up includes a bit.

Obtained from:	TrustedBSD Project
2006-12-23 00:10:36 +00:00
Robert Watson
acd3428b7d Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
specific privilege names to a broad range of privileges.  These may
require some future tweaking.

Sponsored by:           nCircle Network Security, Inc.
Obtained from:          TrustedBSD Project
Discussed on:           arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
                        Alex Lyashkov <umka at sevcity dot net>,
                        Skip Ford <skip dot ford at verizon dot net>,
                        Antoine Brodin <antoine dot brodin at laposte dot net>
2006-11-06 13:42:10 +00:00
Konstantin Belousov
9a969e626c The attempt to rename "." with MAC framework compiled in would cause attempt
to twice unlock the vnode. Check that ni_vp and ni_dvp are different before
doing second unlock.

Reviewed by:	rwatson
Approved by:	pjd (mentor)
MFC after:	1 week
2006-10-26 13:20:28 +00:00
Robert Watson
aed5570872 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
Tor Egge
a1e363f256 Add mnt_noasync counter to better handle interleaved calls to nmount(),
sync() and sync_fsync() without losing MNT_ASYNC.  Add MNTK_ASYNC flag
which is set only when MNT_ASYNC is set and mnt_noasync is zero, and
check that flag instead of MNT_ASYNC before initiating async io.
2006-09-26 04:15:59 +00:00
Tor Egge
5da56ddb21 Use mount interlock to protect all changes to mnt_flag and mnt_kern_flag.
This eliminates a race where MNT_UPDATE flag could be lost when nmount()
raced against sync(), sync_fsync() or quotactl().
2006-09-26 04:12:49 +00:00
Pawel Jakub Dawidek
783deec19e There is no need to set 'sp' to NULL anymore. 2006-09-20 07:27:05 +00:00
Tor Egge
4e59868e08 Copy stat information from mount structure before it can change identity. 2006-09-20 00:32:07 +00:00
Robert Watson
5702e0965e Declare security and security.bsd sysctl hierarchies in sysctl.h along
with other commonly used sysctl name spaces, rather than declaring them
all over the place.

MFC after:	1 month
Sponsored by:	nCircle Network Security, Inc.
2006-09-17 20:00:36 +00:00
John Baldwin
9802d04ce0 Fix some bugs in the previous revision (1.419). Don't perform extra
vfs_rel() on the mountpoint if the MAC checks fail in kern_statfs() and
kern_fstatfs().  Similarly, don't perform an extra vfs_rel() if we get
a doomed vnode in kern_fstatfs(), and handle the case of mp being NULL
(for some doomed vnodes) by conditionalizing the vfs_rel() in
kern_fstatfs() on mp != NULL.

CID:		1517
Found by:	Coverity Prevent (tm) (kern_fstatfs())
Pointy hat to:	jhb
2006-08-02 15:27:48 +00:00
John Baldwin
ea175645b4 Hold the reference on the mountpoint slightly longer in kern_statfs() and
kern_fstatfs() so that it is still held when prison_enforce_statfs() is
called (since that function likes to poke and prod at the mountpoint
structure).

MFC after:	3 days
2006-07-27 20:00:27 +00:00
John Baldwin
2f198e899a Call change_dir() instead of duplicating the code in fchdir(). 2006-07-19 18:30:33 +00:00
John Baldwin
be5747d5b5 - Add conditional VFS Giant locking to getdents_common() (linux ABIs),
ibcs2_getdents(), ibcs2_read(), ogetdirentries(), svr4_sys_getdents(),
  and svr4_sys_getdents64() similar to that in getdirentries().
- Mark ibcs2_getdents(), ibcs2_read(), linux_getdents(), linux_getdents64(),
  linux_readdir(), ogetdirentries(), svr4_sys_getdents(), and
  svr4_sys_getdents64() MPSAFE.
2006-07-11 20:52:08 +00:00
Wayne Salamon
65ee602e0c Audit the remaining parameters to the extattr system calls. Generate
the audit records for those calls.

Obtained from: TrustedBSD Project
Approved by: rwatson (mentor)
2006-07-06 19:33:38 +00:00
Robert Watson
6e79e6f805 Audit command, uid arguments for quotactl().
Audit the mode argument to mkfifo().
Audit the target path passed to symlink().

Submitted by:	wsalamon
Obtained from:	TrustedBSD Project
2006-06-05 13:34:23 +00:00
Jeff Roberson
3bbd6d8ae6 - Release the references acquired by VOP_GETWRITEMOUNT and vfs_getvfs().
Discussed with:	tegge
Tested by:	kris
Sponsored by:	Isilon Systems, Inc.
2006-03-31 03:54:20 +00:00
John Baldwin
861dab08e7 Change vn_open() to honor the MPSAFE flag in the passed in nameidata object
and use that instead of testing fdidx against -1 to determine if it should
release Giant if Giant was locked due to the requested file residing on a
non-MPSAFE VFS.

Discussed with:	jeff
2006-03-28 21:22:08 +00:00
Jeff Roberson
77c79550af - Remove explicit calls to lock and unlock Giant and replace them with
VFS_LOCK_GIANT/VFS_UNLOCK_GIANT calls.  This completely removes Giant
   acquisition in the syscall path for ffs.

Bug fix to kern_fhstatfs from:	Todd Miller <Todd.Miller@sparta.com>
Sponsored by:	Isilon Systems, Inc.
2006-03-21 23:58:37 +00:00
Paul Saab
6308f39da8 use strlcpy in cvtstatfs and copy_statfs instead of bcopy to ensure
the copied strings are properly terminated.

bzero the statfs32 struct in copy_statfs.
2006-03-04 00:09:09 +00:00
Paul Saab
6815739e00 Don't truncate f_mntfromname & f_mntonname to 16 characters when
translating statfs into ostatfs.  This allows 4.x binaries making
statfs calls to work on 6.x.
2006-03-03 07:20:54 +00:00
Jeff Roberson
8febcfb92f - Use vfs_ref/rel to protect a mountpoint from going away while VFS_STATFS
is being called.  Be sure to grab the ref before we unlock the vnode to
   prevent the mount from disappearing.

Tested by:	kris
2006-02-23 05:18:07 +00:00