before the MAC check so that we pass the flags field into the MAC
check properly initialized. This didn't affect any current MAC
modules since they didn't care what the flags argument was (as
they were primarily interested in the fact that it was a meta-data
write, not the contents of the write), but would be relevant to
future modules relying on that field.
Submitted by: Mike Halderman <mrh@spawar.navy.mil>
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
than having change_dir() release the vnode lock on success, hold the
lock so that we can use it later when invoking MAC checks and
VOP_ACCESS() in the chroot() code. Update the comment to reflect
this calling convention. Update callers to unlock the vnode
lock. Correct a typo regarding vnode naming in the MAC case that
crept in via the previous patch applied.
cases: we might multiply vrele() a vnode when certain classes of
failures occur. This appears to stem from earlier Giant/file
descriptor lock pushdown and restructuring.
Submitted by: maxim
pointer types, and remove a huge number of casts from code using it.
Change struct xfile xf_data to xun_data (ABI is still compatible).
If we need to add a #define for f_data and xf_data we can, but I don't
think it will be necessary. There are no operational changes in this
commit.
The leak in lseek was introduced in vfs_syscalls.c revision 1.218.
The leak in do_dup was introduced in kern_descrip.c revision 1.158.
Submitted by: iedowse
missed. This bug has been present since the vn_start_write() and
vn_finished_write() calls were first added in revision 1.159. When
the case is triggered, any attempts to create snapshots on the
filesystem will deadlock and also prevent further write activity
on that filesystem.
to conform to 1003.1-2001. Make it possible for applications to actually
tell whether or not asynchronous I/O is supported.
Since FreeBSD's aio implementation works on all descriptor types, don't
call down into file or vnode ops when [f]pathconf() is asked about
_PC_ASYNC_IO; this avoids the need for every file and vnode op to know about
it.
creation, deletion, and rename. There are one or two other stray
cases I'll catch in follow-up commits (such as unix domain socket
creation); this permits MAC policy modules to limit the ability to
perform these operations based on existing UNIX credential / vnode
attributes, extended attributes, and security labels. In the rename
case using MAC, we now have to lock the from directory and file
vnodes for the MAC check, but this is done only in the MAC case,
and the locks are immediately released so that the remainder of the
rename implementation remains the same. Because the create check
takes a vattr to know object type information, we now initialize
additional fields in the VATTR passed to VOP_SYMLINK() in the MAC
case.
Approved by: re
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
revision 1.218. This bug caused a "struct file" reference to be
leaked if VOP_ADVLOCK(), vn_start_write(), or mac_check_vnode_write()
failed during the open operation.
PR: kern/43739
Reported by: Arne Woerner <woerner@mediabase-gmbh.de>
point that instruments the creation of hard links. Policy implementations
to follow.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
wasn't doing. Rather than just lock and unlock the vnode around the call
to VOP_FSYNC(), implement rwatson's suggestion to lock the file vnode
in kern_link() before calling VOP_LINK(), since the other filesystems
also locked the file vnode right away in their link methods. Remove the
locking and and unlocking from the leaf filesystem link methods.
Reviewed by: rwatson, bde (except for the unionfs_link() changes)
Changed rename(2) to follow the letter of the POSIX spec. POSIX
requires rename() to have no effect if its args "resolve to the same
existing file". I think "file" can only reasonably be read as referring
to the inode, although the rationale and "resolve" seem to say that
sameness is at the level of (resolved) directory entries.
ext2fs_vnops.c, ufs_vnops.c:
Replaced code that gave the historical BSD behaviour of removing one
link name by checks that this code is now unreachable. This fixes
some races. All vnodes needed to be unlocked for the removal, and
locking at another level using something like IN_RENAME was not even
attempted, so it was possible for rename(x, y) to return with both x
and y removed even without any unlink(2) syscalls (one process can
remove x using rename(x, y) and another process can remove y using
rename(y, x)).
Prodded by: alfred
MFC after: 8 weeks
PR: 42617
a kernel-internal kern_*() version and a wrapper that is called via
the syscall vector table. For paths and structure pointers, the
internal version either takes a uio_seg parameter or requires the
caller to copyin() the data to kernel memory as appropiate. This
will permit emulation layers to use these syscalls without having
to copy out translated arguments to the stack gap.
Discussed on: -arch
Review/suggestions: bde, jhb, peter, marcel
for mac_check_vnode_{poll,read,stat,write}(). Pass in fp->f_cred
when calling these checks with a struct file available. Otherwise,
pass NOCRED. All currently MAC policies use active_cred, but
could now offer the cached credential semantic used for the base
system security model.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
mac_check_vnode_poll(), mac_check_vnode_read(), mac_check_vnode_write().
This improves the consistency with other existing vnode checks, and
allows policies to avoid implementing switch statements to determine
what operations they do and do not want to authorize.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
fo_read() and fo_write(): explicitly use the cred argument to fo_poll()
as "active_cred" using the passed file descriptor's f_cred reference
to provide access to the file credential. Add an active_cred
argument to fo_stat() so that implementers have access to the active
credential as well as the file credential. Generally modify callers
of fo_stat() to pass in td->td_ucred rather than fp->f_cred, which
was redundantly provided via the fp argument. This set of modifications
also permits threads to perform these operations on behalf of another
thread without modifying their credential.
Trickle this change down into fo_stat/poll() implementations:
- badfo_poll(), badfo_stat(): modify/add arguments.
- kqueue_poll(), kqueue_stat(): modify arguments.
- pipe_poll(), pipe_stat(): modify/add arguments, pass active_cred to
MAC checks rather than td->td_ucred.
- soo_poll(), soo_stat(): modify/add arguments, pass fp->f_cred rather
than cred to pru_sopoll() to maintain current semantics.
- sopoll(): moidfy arguments.
- vn_poll(), vn_statfile(): modify/add arguments, pass new arguments
to vn_stat(). Pass active_cred to MAC and fp->f_cred to VOP_POLL()
to maintian current semantics.
- vn_close(): rename cred to file_cred to reflect reality while I'm here.
- vn_stat(): Add active_cred and file_cred arguments to vn_stat()
and consumers so that this distinction is maintained at the VFS
as well as 'struct file' layer. Pass active_cred instead of
td->td_ucred to MAC and to VOP_GETATTR() to maintain current semantics.
- fifofs: modify the creation of a "filetemp" so that the file
credential is properly initialized and can be used in the socket
code if desired. Pass ap->a_td->td_ucred as the active
credential to soo_poll(). If we teach the vnop interface about
the distinction between file and active credentials, we would use
the active credential here.
Note that current inconsistent passing of active_cred vs. file_cred to
VOP's is maintained. It's not clear why GETATTR would be authorized
using active_cred while POLL would be authorized using file_cred at
the file system level.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
- v_vflag is protected by the vnode lock and is used when synchronization
with VOP calls is needed.
- v_iflag is protected by interlock and is used for dealing with vnode
management issues. These flags include X/O LOCK, FREE, DOOMED, etc.
- All accesses to v_iflag and v_vflag have either been locked or marked with
mp_fixme's.
- Many ASSERT_VOP_LOCKED calls have been added where the locking was not
clear.
- Many functions in vfs_subr.c were restructured to provide for stronger
locking.
Idea stolen from: BSD/OS
kernel access control.
Invoke appropriate MAC framework entry points to authorize readdir()
operations in the native ABI.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
kernel access control.
Instrument chdir() and chroot()-related system calls to invoke
appropriate MAC entry points to authorize the two operations.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
kernel access control.
Implement MAC framework access control entry points relating to
operations on mountpoints. Currently, this consists only of
access control on mountpoint listing using the various statfs()
variations. In the future, it might also be desirable to
implement checks on mount() and unmount().
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
open() of fhopen(). Currently this has no actual affect due to the
treatment of VAPPEND in vaccess() and vaccess_acl() as a subset of
VWRITE, but when MAC comes in, MAC will distinguish the two. Note:
if any file systems are cutting their own permission models, they
may wish to now take this into account.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
support creation times such as UFS2) to the value of the
modification time if the value of the modification time is older
than the current creation time. See utimes(2) for further details.
Sponsored by: DARPA & NAI Labs.
filedesc is already locked rather than having chroot() unlock the
filedesc so chroot_refuse_vdir_fds() can immediately relock it.
- Reorder chroot() a bitso that we do the namei lookup before checking
the process's struct filedesc. This closes at least one potential race
and allows us to only acquire the filedsec lock once in chroot().
- Push down Giant slightly into chroot().
The file vfs_conf.c which was dealing with root mounting has
been repo-copied into vfs_mount.c to preserve history.
This makes nmount related development easier, and help reducing
the size of vfs_syscalls.c, which is still an enormous file.
Reviewed by: rwatson
Repo-copy by: peter
direct calls for the two places where the kernel calls into soft
updates code. Set up the hooks in softdep_initialize() and NULL
them out in softdep_uninitialize(). This change allows soft updates
to function correctly when ufs is loaded as a module.
Reviewed by: mckusick
vnode in the case that the target exists and is the same vnode as
the parent (i.e. "mkdir ."). The namei() call does not leave the
vnode locked in this case even though you might expect it to.
This bug was mostly harmless in practice because unlocking an already
unlocked vnode currently does not trigger any panics or warnings.
Reviewed by: jeff
64-bit architectures that was introduced in the UFS2 code
merge two days ago. The stat structure change that caused
the problem was the addition of the file create time.
Submitted by: Bruce Evans <bde@zeta.org.au>
Sponsored by: DARPA & NAI Labs.
