zack.kirsch at isilon.com for a race between nfsrv_freeopen()
and nfsrv_getlockfile() in the experimental NFS server that
he found during testing. Although nfsrv_freeopen() holds a
sleep lock on the lock file structure when called with
cansleep != 0, nfsrv_getlockfile() could still search the
list, once it acquired the NFSLOCKSTATE() mutex. I believe
that acquiring the mutex in nfsrv_freeopen() fixes the race.
MFC after: 2 weeks
that it works correctly for ZFS file handles. It is possible to
have two ZFS file handles that differ only in the bytes in the
fid_reserved field of the generic "struct fid" and comparing the
bytes in fid_data didn't catch this case. This patch changes the
macro to compare all bytes of "struct fid".
Tested by: gull at gull.us
MFC after: 2 weeks
NFSv2,3 byte range locking is attempted. A fix that allows the
nlm_advlock() to work with both clients is in progress, but
may take a while. As such, I am doing this commit so that
the kernel doesn't panic in the meantime.
Submitted by: jh
MFC after: 2 weeks
directories for purposes of validating name cache entries. This
closes races where two updates to a file or directory within the same
second could result in stale entries in the name cache. While here,
remove the 'n_expiry' field as it is no longer used.
Reviewed by: rmacklem
MFC after: 1 week
upper layer. Until now, unionfs prevents to use that kind of
file system as upper layer. This time, I changed to allow
that kind of file system as upper layer. By this change, you
can use whiteout not supporting file system (e.g., especially
for tmpfs) as upper layer. It's very useful for combination of
tmpfs as upper layer and read only file system as lower layer.
By difinition, without whiteout support from the file system
backing the upper layer, there is no way that delete and rename
operations on lower layer objects can be done. EOPNOTSUPP is
returned for this kind of operations as generated by VOP_WHITEOUT()
along with any others which would make modifica tions to the
lower layer, such as chmod(1).
This change is suggested by ed.
Submitted by: ed
client to return an error when rabp is not set, so it
behaves the same way as the regular NFS client for this
case. It does not affect NFSv4, since nfs_getcacheblk()
only fails for "intr" mounts and NFSv4 can't use the
"intr" mount option.
MFC after: 2 weeks
of the lower level vnode is incremented to greater than 1 when
the upper level vnode's v_usecount is greater than one. This
is necessary for the NFS clients, so that they will do a silly
rename of the file instead of actually removing it when the
file is still in use. It is "racy", since the v_usecount is
incremented in many places in the kernel with
minimal synchronization, but an extraneous silly rename is
preferred to not doing a silly rename when it is required.
The only other file systems that currently check the value
of v_usecount in their VOP_REMOVE() functions are nwfs and
smbfs. These file systems choose to fail a remove when the
v_usecount is greater than 1 and I believe will function
more correctly with this patch, as well.
Tested by: to.my.trociny at gmail.com
Submitted by: to.my.trociny at gmail.com (earlier version)
Reviewed by: kib
MFC after: 2 weeks
nfsd_recalldelegation() function, since this function is called
by nfsd threads when they are handling NFSv2 or NFSv3 RPCs, where
no reference count would have been acquired.
MFC after: 2 weeks
the correct mutex when checking nfsv4root_lock. Although this
could be fixed by adding mutex lock/unlock calls, zack.kirsch at
isilon.com suggested a better fix that uses a non-blocking
acquisition of a reference count on nfsv4root_lock. This fix
allows the weird NFSLOCKSTATE(); NFSUNLOCKSTATE(); synchronization
to be deleted. This patch applies this fix.
Tested by: zack.kirsch at isilon.com
MFC after: 2 weeks
devfs_populate(). This is a prerequisite for the automatic removal of
empty directories which will be committed in the future.
Reviewed by: kib (previous version)
Right now unionfs only allows filesystems to be mounted on top of
another if it supports whiteouts. Even though I have sent a patch to
daichi@ to let unionfs work without it, we'd better also add support for
whiteouts to tmpfs.
This patch implements .vop_whiteout and makes necessary changes to
lookup() and readdir() to take them into account. We must also make sure
that when adding or removing a file, we honour the componentname's
DOWHITEOUT and ISWHITEOUT, to prevent duplicate filenames.
MFC after: 1 month
LK_CANRECURSE after a lock is created. Use them to implement macros that
otherwise manipulated the flags directly. Assert that the associated
lockmgr lock is exclusively locked by the current thread when manipulating
these flags to ensure the flag updates are safe. This last change required
some minor shuffling in a few filesystems to exclusively lock a brand new
vnode slightly earlier.
Reviewed by: kib
MFC after: 3 days
if the device file appears during or after the link creation.
User created symbolic links are now inserted at the head of the
directory entry list after the "." and ".." entries. A new directory
entry flag DE_COVERED indicates that an entry is covered by a symbolic
link.
PR: kern/114057
Reviewed by: kib
Idea from: kib
Discussed on: freebsd-current (mostly silence)
1. Use unsigned rather than signed lengths
2. Bound messages to/from Venus to VC_MAXMSGSIZE
3. Bound messages to/from general user processes to VC_MAXDATASIZE
4. Update comment regarding data limits for pioctl
Without (1) and (3), it may be possible for unprivileged user processes to
read sensitive portions of kernel memory. This issue is only present if
the Coda kernel module is loaded and venus (the userspace Coda daemon) is
running and has /coda mounted.
As Coda is considered experimental and production use is warned against in
the coda(4) man page, and because Coda must be explicitly configured for a
configuration to be vulnerable, we won't be issuing a security advisory.
However, if you are using Coda, then you are advised to apply these fixes.
Reported by: Dan J. Rosenberg <drosenberg at vsecurity.com>
Obtained from: NetBSD (Christos Zoulas)
Security: Kernel memory disclosure; no advisory as feature experimental
MFC after: 3 days
cdev will never be destroyed. Propagate the flag to devfs vnodes as
VV_ETERNVALDEV. Use the flags to avoid acquiring devmtx and taking a
thread reference on such nodes.
In collaboration with: pho
MFC after: 1 month
which I mistakenly thought was correct w.r.t. style(9), back
to int and add the checks for != 0. This is just a stylistic
modification.
MFC after: 1 week
module that can be used by both the regular and experimental nfs
clients. This fixes the problem reported by jh@ where /dev/nfslock
would be registered twice when both nfs clients were used.
I also defined the size of the lm_fh field to be the correct value,
as it should be the maximum size of an NFSv3 file handle.
Reviewed by: jh
MFC after: 2 weeks
MPSAFE flag to cn_flags so that it doesn't panic. The panics weren't
seen since nfsdumpstate(8) is broken for the "-l" case, so this
was never done. I'll do a separate commit to fix nfsdumpstate(8).
Submitted by: zack.kirsch at isilon.com
MFC after: 2 weeks
NFSv4 client, so that attributes are not acquired from the server
when a delegation for the file is held. This can reduce the number
of Getattr Ops significantly.
MFC after: 2 weeks
count on nfsv4rootfs_lock when dumping state, since these functions
are not called by nfsd threads. Without this reference count, it
is possible for an nfsd thread to acquire an exclusive lock on
nfsv4rootfs_lock while the dump is in progress and then change the
lists, potentially causing a crash.
Reported by: zack.kirsch at isilon.com
MFC after: 2 weeks
implementation in 8.0 and later as its flags field does not hold dynamic
state such as waiters flags, but is only modified in lockinit() aside
from VN_LOCK_*().
Discussed with: attilio
changed to defer the setting of VN_LOCK_ASHARE() (which clears LK_NOSHARE
in the vnode lock's flags) until after they had determined if the vnode was
a FIFO. This occurs after the vnode has been inserted a VFS hash or some
similar table, so it is possible for another thread to find this vnode via
vget() on an i-node number and block on the vnode lock. If the lockmgr
interlock (vnode interlock for vnode locks) is not held when clearing the
LK_NOSHARE flag, then the lk_flags field can be clobbered. As a result
the thread blocked on the vnode lock may never get woken up. Fix this by
holding the vnode interlock while modifying the lock flags in this case.
MFC after: 3 days
to avoid sending multiple ACCESS/GETATTR RPCs during a single open()
between VOP_LOOKUP() and VOP_OPEN(). Now we always send the RPC in
VOP_LOOKUP() and not VOP_OPEN() in the cases that multiple RPCs could be
sent.
MFC after: 2 weeks
Move attribute cache flushes from VOP_OPEN() to VOP_LOOKUP() to provide
more graceful recovery for stale filehandles and eliminate the need for
conditionally clearing the attribute cache in the !NMODIFIED case in
VOP_OPEN().
Reviewed by: rmacklem
MFC after: 2 weeks
released a reference count on nfsv4rootfs_lock erroneously when
administrative revocation of state was done.
Submitted by: zack.kirsch at isilon.com
MFC after: 2 weeks
predate the issue of a delegation are not cached once the delegation
is held. This is necessary, since cached attributes remain valid
while the delegation is held.
MFC after: 2 weeks
server so that the modules will load when kernels are built with
none of the NFS* configuration options specified. I believe this
resolves the problems reported by PR kern/144458 and the email on
freebsd-stable@ posted by Dmitry Pryanishnikov on June 13.
Tested by: kib
PR: kern/144458
Reviewed by: kib
MFC after: 1 week
DIAGNOSTIC and #ifndef DIAGNOSTIC for debug assertions, prefer
KASSERT(). Also change one #ifdef DIAGNOSTIC in the new nfs server.
Submitted by: Mikolaj Golub <to.my.trociny gmail com>
MFC after: 2 weeks
via %s
Most of the cases looked harmless, but this is done for the sake of
correctness. In one case it even allowed to drop an intermediate buffer.
Found by: clang
MFC after: 2 week
directory entry. Use the new function in devfs_fqpn(), devfs_lookupx()
and devfs_vptocnp() instead of manually resolving the parent entry.
Reviewed by: kib