Home | History | Annotate | Download | only in union
History log of /src/sys/fs/union/union_vfsops.c
RevisionDateAuthorComments
 1.88  18-May-2024  thorpej Remove unnecessary include of <sys/malloc.h>.
 1.87  13-Feb-2023  hannken When mounting a union file system set its lower mount only on success.

Reported-by: syzbot+b81b69971581b4f4db00@syzkaller.appspotmail.com
 1.86  06-Feb-2023  hannken Set IMNT_MPSAFE only if all lower layers have it set.
 1.85  21-Nov-2022  hannken branches: 1.85.2;
When testing whiteout support on the underlying file system
union_mount() should not use a NULL componentname as not all
file systems can handle it.

Use static { LOOKUP, NOCRED } componentname instead.

Reported-by: syzbot+ecda308a1dd9652836d0@syzkaller.appspotmail.com
Reported-by: syzbot+9b687847ee5f43e94ca3@syzkaller.appspotmail.com
Reported-by: syzbot+9f9d1a841734f9f50de2@syzkaller.appspotmail.com
 1.84  04-Nov-2022  hannken Add a helper to set or clear lower mount and use it.
Always add a reference to the lower mount.

Ride 9.99.105
 1.83  12-Sep-2022  christos kmem_alloc -> kmem_zalloc, thanks Rin.
 1.82  11-Sep-2022  christos - avoid another credential leak on error from Chris J-D
(chris at accessvector dot net)
- KNF
- use kmem
 1.81  16-Mar-2020  pgoyette Use the module subsystem's ability to process SYSCTL_SETUP() entries to
automate installation of sysctl nodes.

Note that there are still a number of device and pseudo-device modules
that create entries tied to individual device units, rather than to the
module itself. These are not changed.
 1.80  17-Jan-2020  ad VFS_VGET(), VFS_ROOT(), VFS_FHTOVP(): give them a "int lktype" argument, to
allow us to get shared locks (or no lock) on the returned vnode. Matches
FreeBSD.
 1.79  20-Feb-2019  hannken branches: 1.79.4; 1.79.6;
Set "mnt_lower" before the first file system operation on the new file system.
 1.78  01-Apr-2017  riastradh branches: 1.78.14;
KASSERT(mutex_owned(vp->v_interlock)) in vnode iterator selector.
 1.77  06-Mar-2017  hannken Add field "mnt_lower" to "struct mount" to track the file system
a layered file system is mounted on.

Welcome to 7.99.65
 1.76  17-Feb-2017  hannken Add generic genfs_suspendctl() and use it for all file systems.
Layered file systems need work.
 1.75  23-Jul-2015  hannken branches: 1.75.2; 1.75.4;
union_unmount: use vfs_vnode_iterator to count attached vnodes.
 1.74  16-Feb-2015  hannken Change union to vcache. Use address of the union node as key.

It would be better to use (uppervp, lowervp) as key, but either
may be NULL and may change any time.
 1.73  18-Oct-2014  snj branches: 1.73.2;
src is too big these days to tolerate superfluous apostrophes. It's
"its", people!
 1.72  16-Apr-2014  maxv An (un)privileged user can easily make the kernel dereference a NULL
pointer.

The kernel allows 'data' to be NULL; it's the fs's responsibility to
ensure that it isn't NULL (if the fs actually needs data).

ok christos@
 1.71  23-Mar-2014  hannken branches: 1.71.2;
Change all vfsops to use C99 designated initializers.

No functional changes intended.
 1.70  25-Feb-2014  pooka Ensure that the top level sysctl nodes (kern, vfs, net, ...) exist before
the sysctl link sets are processed, and remove redundancy.

Shaves >13kB off of an amd64 GENERIC, not to mention >1k duplicate
lines of code.
 1.69  16-Feb-2014  hannken Change union_allocvp() to take an unlocked uppervp and to return the
union node unlocked. Another VI_XLOCK hack is gone.
 1.68  30-Apr-2012  rmind branches: 1.68.2; 1.68.4;
- Replace some malloc(9) uses with kmem(9).
- G/C M_IPMOPTS, M_IPMADDR and M_BWMETER.
 1.67  05-Dec-2011  hannken branches: 1.67.2; 1.67.6; 1.67.8;
The union file system is as stable as other layered file systems so
no longer print a warning to the console.

Gnats is waiting ...
 1.66  23-Nov-2011  hannken branches: 1.66.2;
Use hashinit() / hashdone() to create the union node hash list.

Cleanup the hash lookup in union_allocvp().

Needs more work as there is still a possible deadlock between
union_allocvp() and vclean().
 1.65  21-Nov-2011  hannken Replace flag based union node locking with generic vnode lock, support
shared and nowait locks and protect un_uppervp and un_*sz with mutex.

Mark file system MPSAFE.
 1.64  28-Aug-2011  hannken branches: 1.64.2;
Print the warning message on mount once.

Should fix PR #42795 (patch to make mounting union filesystems less obnoxious)
 1.63  05-Jul-2010  pooka union doesn't use layerfs (avoids panic in kernel bootstrap when
union is compiled in but none of the layer-using file systems are).
 1.62  30-Jun-2010  hannken The directory vnode must be locked before we call VOP_WHITEOUT().

Should fix PR #23986 "problem mounting directories".
 1.61  08-Jan-2010  pooka branches: 1.61.2; 1.61.4;
The VATTR_NULL/VREF/VHOLD/HOLDRELE() macros lost their will to live
years ago when the kernel was modified to not alter ABI based on
DIAGNOSTIC, and now just call the respective function interfaces
(in lowercase). Plenty of mix'n match upper/lowercase has creeped
into the tree since then. Nuke the macros and convert all callsites
to lowercase.

no functional change
 1.60  29-Jun-2009  dholland Convert 67 namei call sites to use namei_simple, in these functions:

check_console, veriexecclose, veriexec_delete, veriexec_file_add,
emul_find_root, coff_load_shlib (sh3 version), coff_load_shlib,
compat_20_sys_statfs, compat_20_netbsd32_statfs,
ELFNAME2(netbsd32,probe_noteless), darwin_sys_statfs,
ibcs2_sys_statfs, ibcs2_sys_statvfs, linux_sys_uselib,
osf1_sys_statfs, sunos_sys_statfs, sunos32_sys_statfs,
ultrix_sys_statfs, do_sys_mount, fss_create_files (3 of 4),
adosfs_mount, cd9660_mount, coda_ioctl, coda_mount, ext2fs_mount,
ffs_mount, filecore_mount, hfs_mount, lfs_mount, msdosfs_mount,
ntfs_mount, sysvbfs_mount, udf_mount, union_mount, sys_chflags,
sys_lchflags, sys_chmod, sys_lchmod, sys_chown, sys_lchown,
sys___posix_chown, sys___posix_lchown, sys_link, do_sys_pstatvfs,
sys_quotactl, sys_revoke, sys_truncate, do_sys_utimes, sys_extattrctl,
sys_extattr_set_file, sys_extattr_set_link, sys_extattr_get_file,
sys_extattr_get_link, sys_extattr_delete_file,
sys_extattr_delete_link, sys_extattr_list_file, sys_extattr_list_link,
sys_setxattr, sys_lsetxattr, sys_getxattr, sys_lgetxattr,
sys_listxattr, sys_llistxattr, sys_removexattr, sys_lremovexattr

All have been scrutinized (several times, in fact) and compile-tested,
but not all have been explicitly tested in action.

XXX: While I haven't (intentionally) changed the use or nonuse of
XXX: TRYEMULROOT in any of these places, I'm not convinced all the
XXX: uses are correct; an audit might be desirable.
 1.59  04-Apr-2009  ad Turn up the volume on the warning message a bit and note that unionfs can
corrupt the underlying file system. This is an old problem but is now
much easier to trigger because VFS has gone fully multithreaded.
 1.58  05-Dec-2008  ad branches: 1.58.4;
PR kern/40110: null, overlay and umap modules loading -> panic (layerfs symbols not there)

Add a layerfs module.
 1.57  28-Jun-2008  rumble branches: 1.57.2; 1.57.4; 1.57.6;
Create sysctl entries during module initialisation and destroy them
appropriately.

Many of these file systems are now ready for modularisation.
 1.56  18-May-2008  ad branches: 1.56.2;
Until these get fixed or replaced:

WARNING: the foo file system is experimental and may be unstable
 1.55  13-May-2008  simonb mnt_data is a pointer, set it to NULL not 0 when we're finished with it.
 1.54  10-May-2008  rumble Convert file systems to dynamically attach with the new module interface.
Make VFS hooks dynamic while we're here and say farewell to VFS_ATTACH and
VFS_HOOKS_ATTACH linksets.

As a consequence, most of the file systems can now be loaded as new style
modules.

Quick sanity check by ad@.
 1.53  29-Apr-2008  ad branches: 1.53.2;
PR kern/38057 ffs makes assuptions about devvp file system
PR kern/33406 softdeps get stuck in endless loop

Introduce VFS_FSYNC() and call it when syncing a block device, if it
has a mounted file system.
 1.52  27-Feb-2008  matt branches: 1.52.2; 1.52.4;
Convert to ansi definitions from old-style definitons.
 1.51  28-Jan-2008  dholland branches: 1.51.2; 1.51.6;
Fix some race conditions in rename.
Introduce a per-FS rename lock and new vfsops to manipulate it.
Get this lock while renaming. Also add another relookup() in do_sys_rename,
which is a hack to kludge around some of the worst deficiencies of
ufs_rename.
reviewed-by: pooka (and an earlier rev by ad)
posted on tech-kern with no objections.
 1.50  08-Dec-2007  pooka Remove cn_lwp from struct componentname. curlwp should be used
from on. The NDINIT() macro no longer takes the lwp parameter and
associates the credentials of the calling thread with the namei
structure.
 1.49  26-Nov-2007  pooka branches: 1.49.2;
Remove the "struct lwp *" argument from all VFS and VOP interfaces.
The general trend is to remove it from all kernel interfaces and
this is a start. In case the calling lwp is desired, curlwp should
be used.

quick consensus on tech-kern
 1.48  31-Jul-2007  pooka branches: 1.48.2; 1.48.4; 1.48.10; 1.48.12;
* nuke the nameidata parameter from VFS_MOUNT(). Nobody on tech-kern
knew what it was supposed to be used for and wrstuden gave a go-ahead
* while rototilling, convert file systems which went easily to
use VFS_PROTOS() instead of manually prototyping the methods
 1.47  26-Jul-2007  pooka Use eopnotsupp() instead of vfs_stdsuspendctl() and retire the latter.
 1.46  17-Jul-2007  pooka branches: 1.46.2;
Make set_statvfs_info() take a parameter for the vfs name instead
of always retrieving it from mp->mnt_op->vfs_name

christos ok
 1.45  12-Jul-2007  dsl Change the VFS_MOUNT() interface so that the 'data' buffer passed to the
fs code is a kernel buffer, pass though the length of the buffer as well.
Since the length of the userspace buffer isn'it (yet) passed through the mount
system call, add a field to the vfsops structure containing the default length.
Split sys_mount() for calls from compat code.
Ride one of the recent kernel version changes - old fs LKMs will load, but
sys_mount() will reject any attempt to use them.
 1.44  08-Apr-2007  hannken Remove now obsolete vn_start_write() and vn_finished_write() and
corresponding flags.

Revert softdep_trackbufs() to its state before vn_start_write() was added.

Remove from struct mount now unneeded flags IMNT_SUSPEND* and
members mnt_writeopcountupper, mnt_writeopcountlower and mnt_leaf.

Welcome to 4.99.17
 1.43  04-Feb-2007  chs branches: 1.43.2; 1.43.6; 1.43.8;
more fixes for the new vnode locking scheme:
- don't use SAVESTART in calls to relookup() from unionfs,
just vref() the desired vnode when we need to.
- fix locking and refcounting in the unionfs EEXIST error cases.
- release any vnode locks before calling VFS_ROOT(), vfs_busy() is enough.
this allows us to simplify union_root() and fix PR 3006.
- union_lock() doesn't handle shared lock requests correctly,
so convert them to exclusive instead. fixes PR 34775.
- in relookup(), avoid reusing "dp" for different purposes,
the error handling wasn't right. (actually just get rid of dp.)
also, change relookup() to ignore LOCKLEAF and always return the
vnode locked since the callers already expect this.
 1.42  19-Jan-2007  hannken New file system suspension API to replace vn_start_write and vn_finished_write.
The suspension helpers are now put into file system specific operations.
This means every file system not supporting these helpers cannot be suspended
and therefore snapshots are no longer possible.

Implemented for file systems of type ffs.

The new API is enabled on a kernel option NEWVNGATE. This option is
not enabled by default in any kernel config.

Presented and discussed on tech-kern with much input from
Bill Studenmund <wrstuden@netbsd.org> and YAMAMOTO Takashi <yamt@netbsd.org>.

Welcome to 4.99.9 (new vfs op vfs_suspendctl).
 1.41  09-Dec-2006  chs a smorgasbord of improvements to vnode locking and path lookup:
- LOCKPARENT is no longer relevant for lookup(), relookup() or VOP_LOOKUP().
these now always return the parent vnode locked. namei() works as before.
lookup() and various other paths no longer acquire vnode locks in the
wrong order via vrele(). fixes PR 32535.
as a nice side effect, path lookup is also up to 25% faster.
- the above allows us to get rid of PDIRUNLOCK.
- also get rid of WANTPARENT (just use LOCKPARENT and unlock it).
- remove an assumption in layer_node_find() that all file systems implement
a recursive VOP_LOCK() (unionfs doesn't).
- require that all file systems supply vfs_vptofh and vfs_fhtovp routines.
fill in eopnotsupp() for file systems that don't support being exported
and remove the checks for NULL. (layerfs calls these without checking.)
- in union_lookup1(), don't change refcounts in the ISDOTDOT case, just
adjust which vnode is locked. fixes PR 33374.
- apply fixes for ufs_rename() from ufs_vnops.c rev. 1.61 to ext2fs_rename().
 1.40  16-Nov-2006  christos branches: 1.40.2;
__unused removal on arguments; approved by core.
 1.39  20-Oct-2006  reinoud Replace the LIST structure mp->mnt_vnodelist to a TAILQ structure since all
vnodes were synced and processed backwards. This meant that the last
accessed node was processed first and the earlierst last.

An extra benefit is the removal of the ugly hack from the Berkly days on
LFS.

In the proces, i've also replaced the various variations hand written loops
by the TAILQ_FOREACH() macro's.
 1.38  12-Oct-2006  christos - sprinkle __unused on function decls.
- fix a couple of unused bugs
- no more -Wno-unused for i386
 1.37  03-Sep-2006  christos branches: 1.37.2; 1.37.4;
add missing initializers
 1.36  23-Jul-2006  ad Use the LWP cached credentials where sane.
 1.35  14-May-2006  elad integrate kauth.
 1.34  14-Apr-2006  christos Coverity CID 715: Remove dead code.
 1.33  20-Mar-2006  christos PR/32986: Kouichirou Hiratsuka: Don't proceed with unmounting the filesystem
if vflush failed. Thank to Jeff Ito for adopting a similar fix from FreeBSD.
 1.32  05-Jan-2006  wrstuden branches: 1.32.2; 1.32.4; 1.32.6; 1.32.8; 1.32.10;
Change union_unmount() to not play with the fs root vnode explicitly.
Let it get recycled along with all of the others. This is important
as if the root vnode has already been reclaimed, then we get a panic
when we try to vget it.

This addresses PR: kern/31382
 1.31  11-Dec-2005  christos branches: 1.31.2;
merge ktrace-lwp.
 1.30  23-Sep-2005  jmmv Apply the NFS exports list rototill patch:

- Remove all NFS related stuff from file system specific code.
- Drop the vfs_checkexp hook and generalize it in the new nfs_check_export
function, thus removing redundancy from all file systems.
- Move all NFS export-related stuff from kern/vfs_subr.c to the new
file sys/nfs/nfs_export.c. The former was becoming large and its code
is always compiled, regardless of the build options. Using the latter,
the code is only compiled in when NFSSERVER is enabled. While doing this,
also make some functions in nfs_subs.c conditional to NFSSERVER.
- Add a new command in nfssvc(2), called NFSSVC_SETEXPORTSLIST, that takes a
path and a set of export entries. At the moment it can only clear the
exports list or append entries, one by one, but it is done in a way that
allows setting the whole set of entries atomically in the future (see the
comment in mountd_set_exports_list or in doc/TODO).
- Change mountd(8) to use the nfssvc(2) system call instead of mount(2) so
that it becomes file system agnostic. In fact, all this whole thing was
done to remove a 'XXX' block from this utility!
- Change the mount*, newfs and fsck* userland utilities to not deal with NFS
exports initialization; done internally by the kernel when initializing
the NFS support for each file system.
- Implement an interface for VFS (called VFS hooks) so that several kernel
subsystems can run arbitrary code upon receipt of specific VFS events.
At the moment, this only provides support for unmount and is used to
destroy NFS exports lists from the file systems being unmounted, though it
has room for extension.

Thanks go to yamt@, chs@, thorpej@, wrstuden@ and others for their comments
and advice in the development of this patch.
 1.29  30-Aug-2005  xtraeme Remove __P()
 1.28  24-Aug-2005  nakayama statvfs(2) returns bogus result from union mounted file systems with
`-r' option, since it uses uninitialized buffer in the case of no
lower-layer file system.

So, add M_ZERO to malloc(9) flags to initialize the buffer.
 1.27  29-May-2005  christos branches: 1.27.2;
- rename variables to avoid shadowing.
- add a few const.
 1.26  29-Mar-2005  thorpej - Define a VFS_ATTACH() macro that places a reference to a vfsops structure
into the "vfsops" link set.
- Use VFS_ATTACH() where vfsops are declared for individual file systems.
- In vfsinit(), traverse the "vfsops" link set, rather than vfs_list_initial[].
 1.25  26-Feb-2005  perry branches: 1.25.2;
nuke trailing whitespace
 1.24  02-Jan-2005  thorpej branches: 1.24.2; 1.24.4;
Add the system call and VFS infrastructure for file system extended
attributes.

From FreeBSD.
 1.23  01-Jul-2004  hannken Keep a pointer to the leaf mount. Needed for write gating where a
file system gets suspended and has layered mounts above it.

Welcome to 2.0G

Reviewed by: Bill Studenmund <wrstuden@netbsd.org>
 1.22  31-May-2004  wrstuden Revert last two changes. Since union vnode private data do not follow
layerfs guidelines, whenever layerfs_snapshot() does something, it
won't be correct for unionfs.
 1.21  30-May-2004  tron Include "miscfs/genfs/layer_extern.h" to get prototype for
layerfs_snapshot().
 1.20  29-May-2004  wrstuden unionfs can use layerfs_snapshot() too.
 1.19  25-May-2004  hannken Add ffs internal snapshots. Written by Marshall Kirk McKusick for FreeBSD.

- Not enabled by default. Needs kernel option FFS_SNAPSHOT.
- Change parameters of ffs_blkfree.
- Let the copy-on-write functions return an error so spec_strategy
may fail if the copy-on-write fails.
- Change genfs_*lock*() to use vp->v_vnlock instead of &vp->v_lock.
- Add flag B_METAONLY to VOP_BALLOC to return indirect block buffer.
- Add a function ffs_checkfreefile needed for snapshot creation.
- Add special handling of snapshot files:
Snapshots may not be opened for writing and the attributes are read-only.
Use the mtime as the time this snapshot was taken.
Deny mtime updates for snapshot files.
- Add function transferlockers to transfer any waiting processes from
one lock to another.
- Add vfsop VFS_SNAPSHOT to take a snapshot and make it accessible through
a vnode.
- Add snapshot support to ls, fsck_ffs and dump.

Welcome to 2.0F.

Approved by: Jason R. Thorpe <thorpej@netbsd.org>
 1.18  25-May-2004  atatat Sysctl descriptions under vfs subtree
 1.17  24-May-2004  christos Can't do the trick with using sbp as temporary storage; allocate memory
instead.
 1.16  22-May-2004  christos declare the correct variable; thanks Juan RP.
 1.15  22-May-2004  christos simplify stats taking and avoid the extra copy on the stack.
 1.14  12-May-2004  jrf caddr_t -> void * and removal of some more casts.
 1.13  27-Apr-2004  jrf First pass for some caddr_t removal and changes to get rid of it where we
no longer use and/or need it

- removed casts from unionfs, deadfs and fdesc
(there are more to hunt down still)
- changed vfs_quotactl args argumet from caddr_t to void *
- changed vfs_quotactl structures/callers to reflect the api change

Compiled fine and ran for about a day. Approved/reviewed by
christos@netbsd.org and gimpy@netbsd.org.
 1.12  21-Apr-2004  christos Replace the statfs() family of system calls with statvfs().
Retain binary compatibility.
 1.11  24-Mar-2004  atatat branches: 1.11.2;
Tango on sysctl_createv() and flags. The flags have all been renamed,
and sysctl_createv() now uses more arguments.
 1.10  04-Dec-2003  atatat Dynamic sysctl.

Gone are the old kern_sysctl(), cpu_sysctl(), hw_sysctl(),
vfs_sysctl(), etc, routines, along with sysctl_int() et al. Now all
nodes are registered with the tree, and nodes can be added (or
removed) easily, and I/O to and from the tree is handled generically.

Since the nodes are registered with the tree, the mapping from name to
number (and back again) can now be discovered, instead of having to be
hard coded. Adding new nodes to the tree is likewise much simpler --
the new infrastructure handles almost all the work for simple types,
and just about anything else can be done with a small helper function.

All existing nodes are where they were before (numerically speaking),
so all existing consumers of sysctl information should notice no
difference.

PS - I'm sorry, but there's a distinct lack of documentation at the
moment. I'm working on sysctl(3/8/9) right now, and I promise to
watch out for buses.
 1.9  07-Aug-2003  agc Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.
 1.8  29-Jun-2003  fvdl branches: 1.8.2;
Back out the lwp/ktrace changes. They contained a lot of colateral damage,
and need to be examined and discussed more.
 1.7  29-Jun-2003  thorpej Undo part of the ktrace/lwp changes. In particular:
* Remove the "lwp *" argument that was added to vget(). Turns out
that nothing actually used it!
* Remove the "lwp *" arguments that were added to VFS_ROOT(), VFS_VGET(),
and VFS_FHTOVP(); all they did was pass it to vget() (which, as noted
above, didn't use it).
* Remove all of the "lwp *" arguments to internal functions that were added
just to appease the above.
 1.6  29-Jun-2003  thorpej Fix problems with Darren's ktrace/lwp changes.
 1.5  29-Jun-2003  darrenr More changes for providing lwpid for ktrace (sparc GENERIC built)
 1.4  16-Apr-2003  christos PR/1796: John Kohl: statfs misbehaves under chrooted environments.

- Under chroot it displays only the visible filesystems with appropriate paths.
- The statfs f_mntonname gets adjusted to contain the real path from root.
- While was there, fixed a bug in ext2fs, locking problems with vfs_getfsstat(),
and factored out some of the vfsop statfs() code to copy_statfs_info(). This
fixes the problem where some filesystems forgot to set fsid.
- Made coda look more like a normal fs.
 1.3  17-Mar-2003  jdolecek add comment for one NULL union_vfsops member
 1.2  17-Mar-2003  jdolecek make it possible for UNION fs to be loaded via LKM - instead of
having some #ifdef UNION code in vfs_vnops.c, introduce variable
'vn_union_readdir_hook' which is set to address of appropriate
vn_readdir() hook by union filesystem when it's loaded & mounted
 1.1  16-Mar-2003  jdolecek move union filesystem code from sys/miscfs/union to sys/fs/union
 1.8.2.9  10-Nov-2005  skrll Sync with HEAD. Here we go again...
 1.8.2.8  01-Apr-2005  skrll Sync with HEAD.
 1.8.2.7  04-Mar-2005  skrll Sync with HEAD.

Hi Perry!
 1.8.2.6  17-Jan-2005  skrll Sync with HEAD.
 1.8.2.5  21-Sep-2004  skrll Fix the sync with head I botched.
 1.8.2.4  18-Sep-2004  skrll Sync with HEAD.
 1.8.2.3  24-Aug-2004  skrll Undo part of the ktrace/lwp changes. In particular:
* Remove the "lwp *" argument that was added to vget(). Turns out
that nothing actually used it!
* Remove the "lwp *" arguments that were added to VFS_ROOT(), VFS_VGET(),
and VFS_FHTOVP(); all they did was pass it to vget() (which, as noted
above, didn't use it).
* Remove all of the "lwp *" arguments to internal functions that were added
just to appease the above.
 1.8.2.2  03-Aug-2004  skrll Sync with HEAD
 1.8.2.1  03-Jul-2003  wrstuden LWP-ify union fs.

Note: These changes suffer from the same cnp->cn_lwp issue noted for
ufs. They will need to get fixed at the same time as ufs. The fix is to
add struct lwp * as a parameter to some VOPs.

Note also that most of the cn_lwp references used to be cn_proc references,
so if cnp->cn_lwp is bad to use, unionfs's been naughty for quite some
time.
 1.11.2.2  06-Jan-2006  riz Pull up following revision(s) (requested by wrstuden in ticket #10213):
sys/fs/union/union_vfsops.c: revision 1.32 via patch
Change union_unmount() to not play with the fs root vnode explicitly.
Let it get recycled along with all of the others. This is important
as if the root vnode has already been reclaimed, then we get a panic
when we try to vget it.
This addresses PR: kern/31382
 1.11.2.1  29-May-2004  tron branches: 1.11.2.1.2; 1.11.2.1.4;
Pull up revision 1.18 (requested by atatat in ticket #393):
Sysctl descriptions under vfs subtree
 1.11.2.1.4.1  06-Jan-2006  riz Pull up following revision(s) (requested by wrstuden in ticket #10213):
sys/fs/union/union_vfsops.c: revision 1.32 via patch
Change union_unmount() to not play with the fs root vnode explicitly.
Let it get recycled along with all of the others. This is important
as if the root vnode has already been reclaimed, then we get a panic
when we try to vget it.
This addresses PR: kern/31382
 1.11.2.1.2.1  06-Jan-2006  riz Pull up following revision(s) (requested by wrstuden in ticket #10213):
sys/fs/union/union_vfsops.c: revision 1.32 via patch
Change union_unmount() to not play with the fs root vnode explicitly.
Let it get recycled along with all of the others. This is important
as if the root vnode has already been reclaimed, then we get a panic
when we try to vget it.
This addresses PR: kern/31382
 1.24.4.1  19-Mar-2005  yamt sync with head. xen and whitespace. xen part is not finished.
 1.24.2.1  29-Apr-2005  kent sync with -current
 1.25.2.2  08-Jan-2006  riz Pull up following revision(s) (requested by wrstuden in ticket #1091):
sys/fs/union/union_vfsops.c: revision 1.32
Change union_unmount() to not play with the fs root vnode explicitly.
Let it get recycled along with all of the others. This is important
as if the root vnode has already been reclaimed, then we get a panic
when we try to vget it.
This addresses PR: kern/31382
 1.25.2.1  28-Aug-2005  tron branches: 1.25.2.1.2;
Pull up following revision(s) (requested by nakayama in ticket #708):
sys/fs/union/union_vfsops.c: revision 1.28
statvfs(2) returns bogus result from union mounted file systems with
`-r' option, since it uses uninitialized buffer in the case of no
lower-layer file system.
So, add M_ZERO to malloc(9) flags to initialize the buffer.
 1.25.2.1.2.1  08-Jan-2006  riz Pull up following revision(s) (requested by wrstuden in ticket #1091):
sys/fs/union/union_vfsops.c: revision 1.32
Change union_unmount() to not play with the fs root vnode explicitly.
Let it get recycled along with all of the others. This is important
as if the root vnode has already been reclaimed, then we get a panic
when we try to vget it.
This addresses PR: kern/31382
 1.27.2.8  17-Mar-2008  yamt sync with head.
 1.27.2.7  04-Feb-2008  yamt sync with head.
 1.27.2.6  21-Jan-2008  yamt sync with head
 1.27.2.5  07-Dec-2007  yamt sync with head
 1.27.2.4  03-Sep-2007  yamt sync with head.
 1.27.2.3  26-Feb-2007  yamt sync with head.
 1.27.2.2  30-Dec-2006  yamt sync with head.
 1.27.2.1  21-Jun-2006  yamt sync with head.
 1.31.2.1  15-Jan-2006  yamt sync with head.
 1.32.10.2  24-May-2006  tron Merge 2006-05-24 NetBSD-current into the "peter-altq" branch.
 1.32.10.1  28-Mar-2006  tron Merge 2006-03-28 NetBSD-current into the "peter-altq" branch.
 1.32.8.3  06-May-2006  christos - Move kauth_cred_t declaration to <sys/types.h>
- Cleanup struct ucred; forward declarations that are unused.
- Don't include <sys/kauth.h> in any header, but include it in the c files
that need it.

Approved by core.
 1.32.8.2  19-Apr-2006  elad sync with head.
 1.32.8.1  08-Mar-2006  elad Adapt to kernel authorization KPI.
 1.32.6.4  14-Sep-2006  yamt sync with head.
 1.32.6.3  11-Aug-2006  yamt sync with head
 1.32.6.2  24-May-2006  yamt sync with head.
 1.32.6.1  01-Apr-2006  yamt sync with head.
 1.32.4.2  01-Jun-2006  kardel Sync with head.
 1.32.4.1  22-Apr-2006  simonb Sync with head.
 1.32.2.1  09-Sep-2006  rpaulo sync with head
 1.37.4.2  10-Dec-2006  yamt sync with head.
 1.37.4.1  22-Oct-2006  yamt sync with head
 1.37.2.4  09-Feb-2007  ad Sync with HEAD.
 1.37.2.3  01-Feb-2007  ad Sync with head.
 1.37.2.2  12-Jan-2007  ad Sync with head.
 1.37.2.1  18-Nov-2006  ad Sync with head.
 1.40.2.1  17-Feb-2007  tron Apply patch (requested by chs in ticket #422):
- Fix various deadlock problems with nullfs and unionfs.
- Speed up path lookups by upto 25%.
 1.43.8.1  11-Jul-2007  mjf Sync with head.
 1.43.6.3  20-Aug-2007  ad Sync with HEAD.
 1.43.6.2  15-Jul-2007  ad Sync with head.
 1.43.6.1  10-Apr-2007  ad Sync with head.
 1.43.2.1  15-Apr-2007  yamt sync with head.
 1.46.2.1  15-Aug-2007  skrll Sync with HEAD.
 1.48.12.2  31-Jul-2007  pooka * nuke the nameidata parameter from VFS_MOUNT(). Nobody on tech-kern
knew what it was supposed to be used for and wrstuden gave a go-ahead
* while rototilling, convert file systems which went easily to
use VFS_PROTOS() instead of manually prototyping the methods
 1.48.12.1  31-Jul-2007  pooka file union_vfsops.c was added on branch matt-mips64 on 2007-07-31 21:14:20 +0000
 1.48.10.3  18-Feb-2008  mjf Sync with HEAD.
 1.48.10.2  27-Dec-2007  mjf Sync with HEAD.
 1.48.10.1  08-Dec-2007  mjf Sync with HEAD.
 1.48.4.2  23-Mar-2008  matt sync with HEAD
 1.48.4.1  09-Jan-2008  matt sync with HEAD
 1.48.2.2  09-Dec-2007  jmcneill Sync with HEAD.
 1.48.2.1  27-Nov-2007  joerg Sync with HEAD. amd64 Xen support needs testing.
 1.49.2.1  26-Dec-2007  ad Sync with head.
 1.51.6.4  17-Jan-2009  mjf Sync with HEAD.
 1.51.6.3  29-Jun-2008  mjf Sync with HEAD.
 1.51.6.2  02-Jun-2008  mjf Sync with HEAD.
 1.51.6.1  03-Apr-2008  mjf Sync with HEAD.
 1.51.2.1  24-Mar-2008  keiichi sync with head.
 1.52.4.5  11-Aug-2010  yamt sync with head.
 1.52.4.4  11-Mar-2010  yamt sync with head
 1.52.4.3  18-Jul-2009  yamt sync with head.
 1.52.4.2  04-May-2009  yamt sync with head.
 1.52.4.1  16-May-2008  yamt sync with head.
 1.52.2.2  04-Jun-2008  yamt sync with head
 1.52.2.1  18-May-2008  yamt sync with head.
 1.53.2.2  18-Sep-2008  wrstuden Sync with wrstuden-revivesa-base-2.
 1.53.2.1  23-Jun-2008  wrstuden Sync w/ -current. 34 merge conflicts to follow.
 1.56.2.1  03-Jul-2008  simonb Sync with head.
 1.57.6.3  25-Apr-2014  sborrill Pull up the following revisions(s) (requested by maxv in ticket #1901):
sys/kern/vfs_syscalls.c: revision 1.478, 1.480 via patch
sys/coda/coda_vfsops.c: revision 1.81
sys/fs/adosfs/advfsops.c: revision 1.70
sys/fs/cd9660/cd9660_vfsops.c: revision 1.84
sys/fs/efs/efs_vfsops.c: revision 1.25
sys/fs/filecorefs/filecore_vfsops.c: revision 1.76
sys/fs/hfs/hfs_vfsops.c: revision 1.31
sys/fs/msdosfs/msdosfs_vfsops.c: revision 1.107
sys/fs/ntfs/ntfs_vfsops.c: revision 1.94
sys/fs/ptyfs/ptyfs_vfsops.c: revision 1.50 via patch
sys/fs/puffs/puffs_vfsops.c: revision 1.110 via patch
sys/fs/smbfs/smbfs_vfsops.c: revision 1.100
sys/fs/sysvbfs/sysvbfs_vfsops.c: revision 1.43
sys/fs/tmpfs/tmpfs_vfsops.c: revision 1.59 via patch
sys/fs/udf/udf_vfsops.c: revision 1.67
sys/fs/union/union_vfsops.c: revision 1.72
sys/fs/unionfs/unionfs_vfsops.c: revision 1.13
sys/kern/vfs_syscalls.c: revision 1.479
sys/miscfs/nullfs/null_vfsops.c: revision 1.88 via patch
sys/miscfs/overlay/overlay_vfsops.c: revision 1.61
sys/miscfs/procfs/procfs_vfsops.c: revision 1.91
sys/miscfs/umapfs/umap_vfsops.c: revision 1.92
sys/nfs/nfs_vfsops.c: revision 1.227
sys/ufs/ext2fs/ext2fs_vfsops.c: revision 1.180
sys/ufs/ffs/ffs_vfsops.c: revision 1.297
sys/ufs/lfs/lfs_vfsops.c: revision 1.321
sys/ufs/mfs/mfs_vfsops.c: revision 1.107

Due to missing checks in the mount syscall, and a wrong assumption on the
file systems side, the kernel could allocate an unbounded or zero-sized
memory buffer, and could dereference a NULL pointer when particular
arguments are given by a user.
 1.57.6.2  17-Sep-2011  bouyer branches: 1.57.6.2.2;
Pull up following revision(s) (requested by hannken in ticket #1667):
sys/fs/union/union_vfsops.c: revision 1.64
Print the warning message on mount once.
=20
Should fix PR #42795 (patch to make mounting union filesystems less =
obnoxious)
=20
=20
 1.57.6.1  04-Apr-2009  snj branches: 1.57.6.1.6;
Pull up following revision(s) (requested by ad in ticket #663):
sys/fs/union/union_vfsops.c: revision 1.59
Turn up the volume on the warning message a bit and note that unionfs can
corrupt the underlying file system. This is an old problem but is now
much easier to trigger because VFS has gone fully multithreaded.
 1.57.6.2.2.1  28-Apr-2014  sborrill Pull up the following revisions(s) (requested by maxv in ticket #1901):
sys/kern/vfs_syscalls.c: revision 1.478, 1.480 via patch
sys/coda/coda_vfsops.c: revision 1.81
sys/fs/adosfs/advfsops.c: revision 1.70
sys/fs/cd9660/cd9660_vfsops.c: revision 1.84
sys/fs/efs/efs_vfsops.c: revision 1.25
sys/fs/filecorefs/filecore_vfsops.c: revision 1.76
sys/fs/hfs/hfs_vfsops.c: revision 1.31
sys/fs/msdosfs/msdosfs_vfsops.c: revision 1.107
sys/fs/ntfs/ntfs_vfsops.c: revision 1.94
sys/fs/ptyfs/ptyfs_vfsops.c: revision 1.50 via patch
sys/fs/puffs/puffs_vfsops.c: revision 1.110 via patch
sys/fs/smbfs/smbfs_vfsops.c: revision 1.100
sys/fs/sysvbfs/sysvbfs_vfsops.c: revision 1.43
sys/fs/tmpfs/tmpfs_vfsops.c: revision 1.59 via patch
sys/fs/udf/udf_vfsops.c: revision 1.67
sys/fs/union/union_vfsops.c: revision 1.72
sys/fs/unionfs/unionfs_vfsops.c: revision 1.13
sys/kern/vfs_syscalls.c: revision 1.479
sys/miscfs/nullfs/null_vfsops.c: revision 1.88 via patch
sys/miscfs/overlay/overlay_vfsops.c: revision 1.61
sys/miscfs/procfs/procfs_vfsops.c: revision 1.91
sys/miscfs/umapfs/umap_vfsops.c: revision 1.92
sys/nfs/nfs_vfsops.c: revision 1.227
sys/ufs/ext2fs/ext2fs_vfsops.c: revision 1.180
sys/ufs/ffs/ffs_vfsops.c: revision 1.297
sys/ufs/lfs/lfs_vfsops.c: revision 1.321
sys/ufs/mfs/mfs_vfsops.c: revision 1.107

Due to missing checks in the mount syscall, and a wrong assumption on the
file systems side, the kernel could allocate an unbounded or zero-sized
memory buffer, and could dereference a NULL pointer when particular
arguments are given by a user.
 1.57.6.1.6.1  28-Apr-2014  sborrill Pull up the following revisions(s) (requested by maxv in ticket #1901):
sys/kern/vfs_syscalls.c: revision 1.478, 1.480 via patch
sys/coda/coda_vfsops.c: revision 1.81
sys/fs/adosfs/advfsops.c: revision 1.70
sys/fs/cd9660/cd9660_vfsops.c: revision 1.84
sys/fs/efs/efs_vfsops.c: revision 1.25
sys/fs/filecorefs/filecore_vfsops.c: revision 1.76
sys/fs/hfs/hfs_vfsops.c: revision 1.31
sys/fs/msdosfs/msdosfs_vfsops.c: revision 1.107
sys/fs/ntfs/ntfs_vfsops.c: revision 1.94
sys/fs/ptyfs/ptyfs_vfsops.c: revision 1.50 via patch
sys/fs/puffs/puffs_vfsops.c: revision 1.110 via patch
sys/fs/smbfs/smbfs_vfsops.c: revision 1.100
sys/fs/sysvbfs/sysvbfs_vfsops.c: revision 1.43
sys/fs/tmpfs/tmpfs_vfsops.c: revision 1.59 via patch
sys/fs/udf/udf_vfsops.c: revision 1.67
sys/fs/union/union_vfsops.c: revision 1.72
sys/fs/unionfs/unionfs_vfsops.c: revision 1.13
sys/kern/vfs_syscalls.c: revision 1.479
sys/miscfs/nullfs/null_vfsops.c: revision 1.88 via patch
sys/miscfs/overlay/overlay_vfsops.c: revision 1.61
sys/miscfs/procfs/procfs_vfsops.c: revision 1.91
sys/miscfs/umapfs/umap_vfsops.c: revision 1.92
sys/nfs/nfs_vfsops.c: revision 1.227
sys/ufs/ext2fs/ext2fs_vfsops.c: revision 1.180
sys/ufs/ffs/ffs_vfsops.c: revision 1.297
sys/ufs/lfs/lfs_vfsops.c: revision 1.321
sys/ufs/mfs/mfs_vfsops.c: revision 1.107

Due to missing checks in the mount syscall, and a wrong assumption on the
file systems side, the kernel could allocate an unbounded or zero-sized
memory buffer, and could dereference a NULL pointer when particular
arguments are given by a user.
 1.57.4.2  28-Apr-2009  skrll Sync with HEAD.
 1.57.4.1  19-Jan-2009  skrll Sync with HEAD.
 1.57.2.1  13-Dec-2008  haad Update haad-dm branch to haad-dm-base2.
 1.58.4.2  23-Jul-2009  jym Sync with HEAD.
 1.58.4.1  13-May-2009  jym Sync with HEAD.

Commit is split, to avoid a "too many arguments" protocol error.
 1.61.4.2  05-Mar-2011  rmind sync with head
 1.61.4.1  03-Jul-2010  rmind sync with head
 1.61.2.1  17-Aug-2010  uebayasi Sync with HEAD.
 1.64.2.3  22-May-2014  yamt sync with head.

for a reference, the tree before this commit was tagged
as yamt-pagecache-tag8.

this commit was splitted into small chunks to avoid
a limitation of cvs. ("Protocol error: too many arguments")
 1.64.2.2  23-May-2012  yamt sync with head.
 1.64.2.1  17-Apr-2012  yamt sync with head
 1.66.2.2  02-Jun-2012  mrg sync to latest -current.
 1.66.2.1  18-Feb-2012  mrg merge to -current.
 1.67.8.1  21-Apr-2014  bouyer Pull up following revision(s) (requested by maxv in ticket #1050):
sys/ufs/chfs/chfs_vfsops.c: revision 1.11
sys/fs/unionfs/unionfs_vfsops.c: revision 1.13
sys/fs/nilfs/nilfs_vfsops.c: revision 1.16
sys/ufs/mfs/mfs_vfsops.c: revision 1.107
sys/fs/sysvbfs/sysvbfs_vfsops.c: revision 1.43
sys/ufs/ffs/ffs_vfsops.c: revision 1.297
sys/kern/vfs_syscalls.c: revision 1.478
sys/kern/vfs_syscalls.c: revision 1.479
sys/fs/puffs/puffs_vfsops.c: revision 1.110
sys/fs/cd9660/cd9660_vfsops.c: revision 1.84
sys/nfs/nfs_vfsops.c: revision 1.227
sys/fs/v7fs/v7fs_vfsops.c: revision 1.10
sys/ufs/ext2fs/ext2fs_vfsops.c: revision 1.180
sys/miscfs/umapfs/umap_vfsops.c: revision 1.92
sys/fs/filecorefs/filecore_vfsops.c: revision 1.76
sys/miscfs/nullfs/null_vfsops.c: revision 1.88
sys/fs/ptyfs/ptyfs_vfsops.c: revision 1.50
sys/coda/coda_vfsops.c: revision 1.81
sys/ufs/lfs/lfs_vfsops.c: revision 1.321
sys/fs/tmpfs/tmpfs_vfsops.c: revision 1.59
sys/fs/hfs/hfs_vfsops.c: revision 1.31
sys/miscfs/overlay/overlay_vfsops.c: revision 1.61
sys/fs/union/union_vfsops.c: revision 1.72
sys/fs/ntfs/ntfs_vfsops.c: revision 1.94
sys/kern/vfs_syscalls.c: revision 1.480
sys/fs/efs/efs_vfsops.c: revision 1.25
sys/kern/vfs_syscalls.c: revision 1.482
sys/fs/msdosfs/msdosfs_vfsops.c: revision 1.107
external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vfsops.c: revision 1.12
sys/miscfs/procfs/procfs_vfsops.c: revision 1.91
sys/fs/smbfs/smbfs_vfsops.c: revision 1.100
sys/fs/adosfs/advfsops.c: revision 1.70
sys/fs/udf/udf_vfsops.c: revision 1.67
Limit check for 'data_len'. Otherwise a (un)privileged user can easily
panic the system by passing a huge size.
ok christos@
An (un)privileged user can easily make the kernel dereference a NULL
pointer.
The kernel allows 'data' to be NULL; it's the fs's responsibility to
ensure that it isn't NULL (if the fs actually needs data).
ok christos@
Some fs's - like kernfs - set their vfs_min_mount_data to zero. Add a check
to prevent an (un)privileged user from requesting a zero-sized allocation
(and thus a panic).
This thing is totally buggy: 'data_len' is modified by the fs, so calling
kmem_free with it while its value has changed since the kmem_alloc is far
from being a good idea.
If the kernel figures out that something mismatches, it will panic
(typically with kernfs).
 1.67.6.1  21-Apr-2014  bouyer Pull up following revision(s) (requested by maxv in ticket #1050):
sys/ufs/chfs/chfs_vfsops.c: revision 1.11
sys/fs/unionfs/unionfs_vfsops.c: revision 1.13
sys/fs/nilfs/nilfs_vfsops.c: revision 1.16
sys/ufs/mfs/mfs_vfsops.c: revision 1.107
sys/fs/sysvbfs/sysvbfs_vfsops.c: revision 1.43
sys/ufs/ffs/ffs_vfsops.c: revision 1.297
sys/kern/vfs_syscalls.c: revision 1.478
sys/kern/vfs_syscalls.c: revision 1.479
sys/fs/puffs/puffs_vfsops.c: revision 1.110
sys/fs/cd9660/cd9660_vfsops.c: revision 1.84
sys/nfs/nfs_vfsops.c: revision 1.227
sys/fs/v7fs/v7fs_vfsops.c: revision 1.10
sys/ufs/ext2fs/ext2fs_vfsops.c: revision 1.180
sys/miscfs/umapfs/umap_vfsops.c: revision 1.92
sys/fs/filecorefs/filecore_vfsops.c: revision 1.76
sys/miscfs/nullfs/null_vfsops.c: revision 1.88
sys/fs/ptyfs/ptyfs_vfsops.c: revision 1.50
sys/coda/coda_vfsops.c: revision 1.81
sys/ufs/lfs/lfs_vfsops.c: revision 1.321
sys/fs/tmpfs/tmpfs_vfsops.c: revision 1.59
sys/fs/hfs/hfs_vfsops.c: revision 1.31
sys/miscfs/overlay/overlay_vfsops.c: revision 1.61
sys/fs/union/union_vfsops.c: revision 1.72
sys/fs/ntfs/ntfs_vfsops.c: revision 1.94
sys/kern/vfs_syscalls.c: revision 1.480
sys/fs/efs/efs_vfsops.c: revision 1.25
sys/kern/vfs_syscalls.c: revision 1.482
sys/fs/msdosfs/msdosfs_vfsops.c: revision 1.107
external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vfsops.c: revision 1.12
sys/miscfs/procfs/procfs_vfsops.c: revision 1.91
sys/fs/smbfs/smbfs_vfsops.c: revision 1.100
sys/fs/adosfs/advfsops.c: revision 1.70
sys/fs/udf/udf_vfsops.c: revision 1.67
Limit check for 'data_len'. Otherwise a (un)privileged user can easily
panic the system by passing a huge size.
ok christos@
An (un)privileged user can easily make the kernel dereference a NULL
pointer.
The kernel allows 'data' to be NULL; it's the fs's responsibility to
ensure that it isn't NULL (if the fs actually needs data).
ok christos@
Some fs's - like kernfs - set their vfs_min_mount_data to zero. Add a check
to prevent an (un)privileged user from requesting a zero-sized allocation
(and thus a panic).
This thing is totally buggy: 'data_len' is modified by the fs, so calling
kmem_free with it while its value has changed since the kmem_alloc is far
from being a good idea.
If the kernel figures out that something mismatches, it will panic
(typically with kernfs).
 1.67.2.1  21-Apr-2014  bouyer Pull up following revision(s) (requested by maxv in ticket #1050):
sys/ufs/chfs/chfs_vfsops.c: revision 1.11
sys/fs/unionfs/unionfs_vfsops.c: revision 1.13
sys/fs/nilfs/nilfs_vfsops.c: revision 1.16
sys/ufs/mfs/mfs_vfsops.c: revision 1.107
sys/fs/sysvbfs/sysvbfs_vfsops.c: revision 1.43
sys/ufs/ffs/ffs_vfsops.c: revision 1.297
sys/kern/vfs_syscalls.c: revision 1.478
sys/kern/vfs_syscalls.c: revision 1.479
sys/fs/puffs/puffs_vfsops.c: revision 1.110
sys/fs/cd9660/cd9660_vfsops.c: revision 1.84
sys/nfs/nfs_vfsops.c: revision 1.227
sys/fs/v7fs/v7fs_vfsops.c: revision 1.10
sys/ufs/ext2fs/ext2fs_vfsops.c: revision 1.180
sys/miscfs/umapfs/umap_vfsops.c: revision 1.92
sys/fs/filecorefs/filecore_vfsops.c: revision 1.76
sys/miscfs/nullfs/null_vfsops.c: revision 1.88
sys/fs/ptyfs/ptyfs_vfsops.c: revision 1.50
sys/coda/coda_vfsops.c: revision 1.81
sys/ufs/lfs/lfs_vfsops.c: revision 1.321
sys/fs/tmpfs/tmpfs_vfsops.c: revision 1.59
sys/fs/hfs/hfs_vfsops.c: revision 1.31
sys/miscfs/overlay/overlay_vfsops.c: revision 1.61
sys/fs/union/union_vfsops.c: revision 1.72
sys/fs/ntfs/ntfs_vfsops.c: revision 1.94
sys/kern/vfs_syscalls.c: revision 1.480
sys/fs/efs/efs_vfsops.c: revision 1.25
sys/kern/vfs_syscalls.c: revision 1.482
sys/fs/msdosfs/msdosfs_vfsops.c: revision 1.107
external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vfsops.c: revision 1.12
sys/miscfs/procfs/procfs_vfsops.c: revision 1.91
sys/fs/smbfs/smbfs_vfsops.c: revision 1.100
sys/fs/adosfs/advfsops.c: revision 1.70
sys/fs/udf/udf_vfsops.c: revision 1.67
Limit check for 'data_len'. Otherwise a (un)privileged user can easily
panic the system by passing a huge size.
ok christos@
An (un)privileged user can easily make the kernel dereference a NULL
pointer.
The kernel allows 'data' to be NULL; it's the fs's responsibility to
ensure that it isn't NULL (if the fs actually needs data).
ok christos@
Some fs's - like kernfs - set their vfs_min_mount_data to zero. Add a check
to prevent an (un)privileged user from requesting a zero-sized allocation
(and thus a panic).
This thing is totally buggy: 'data_len' is modified by the fs, so calling
kmem_free with it while its value has changed since the kmem_alloc is far
from being a good idea.
If the kernel figures out that something mismatches, it will panic
(typically with kernfs).
 1.68.4.1  18-May-2014  rmind sync with head
 1.68.2.2  03-Dec-2017  jdolecek update from HEAD
 1.68.2.1  20-Aug-2014  tls Rebase to HEAD as of a few days ago.
 1.71.2.1  10-Aug-2014  tls Rebase.
 1.73.2.3  28-Aug-2017  skrll Sync with HEAD
 1.73.2.2  22-Sep-2015  skrll Sync with HEAD
 1.73.2.1  06-Apr-2015  skrll Sync with HEAD
 1.75.4.1  21-Apr-2017  bouyer Sync with HEAD
 1.75.2.2  26-Apr-2017  pgoyette Sync with HEAD
 1.75.2.1  20-Mar-2017  pgoyette Sync with HEAD
 1.78.14.2  08-Apr-2020  martin Merge changes from current as of 20200406
 1.78.14.1  10-Jun-2019  christos Sync with HEAD
 1.79.6.1  17-Jan-2020  ad Sync with head.
 1.79.4.1  06-Feb-2023  martin Pull up following revision(s) (requested by hannken in ticket #1587):

sys/fs/union/union_vfsops.c: revision 1.86
sys/miscfs/nullfs/null_vfsops.c: revision 1.101 (via patch)

Set IMNT_MPSAFE only if all lower layers have it set.
 1.85.2.1  06-Feb-2023  martin Pull up following revision(s) (requested by hannken in ticket #68):

sys/fs/union/union_vfsops.c: revision 1.86
sys/miscfs/nullfs/null_vfsops.c: revision 1.101

Set IMNT_MPSAFE only if all lower layers have it set.

RSS XML Feed