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freebsd-dev/sys/gnu/fs/ext2fs/ext2_vnops.c
Bruce Evans 1c1752872f Fixed breakage of mknod() in rev.1.48 of ext2_vnops.c and rev.1.126 of 
ufs_vnops.c:

1) i_ino was confused with i_number, so the inode number passed to
   VFS_VGET() was usually wrong (usually 0U).
2) ip was dereferenced after vgone() freed it, so the inode number
   passed to VFS_VGET() was sometimes not even wrong.

Bug (1) was usually fatal in ext2_mknod(), since ext2fs doesn't have
space for inode 0 on the disk; ino_to_fsba() subtracts 1 from the
inode number, so inode number 0U gives a way out of bounds array
index.  Bug(1) was usually harmless in ufs_mknod(); ino_to_fsba()
doesn't subtract 1, and VFS_VGET() reads suitable garbage (all 0's?)
from the disk for the invalid inode number 0U; ufs_mknod() returns
a wrong vnode, but most callers just vput() it; the correct vnode is
eventually obtained by an implicit VFS_VGET() just like it used to be.

Bug (2) usually doesn't happen.
2000-11-04 08:10:56 +00:00

1217 lines
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/*
* modified for EXT2FS support in Lites 1.1
*
* Aug 1995, Godmar Back (gback@cs.utah.edu)
* University of Utah, Department of Computer Science
*/
/*
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)ufs_vnops.c 8.27 (Berkeley) 5/27/95
* @(#)ext2_vnops.c 8.7 (Berkeley) 2/3/94
* $FreeBSD$
*/
#include "opt_quota.h"
#include "opt_suiddir.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/resourcevar.h>
#include <sys/kernel.h>
#include <sys/stat.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <sys/mount.h>
#include <sys/time.h>
#include <sys/vnode.h>
#include <sys/namei.h>
#include <vm/vm.h>
#include <vm/vm_extern.h>
#include <vm/vnode_pager.h>
#include <sys/signalvar.h>
#include <ufs/ufs/dir.h>
#include <ufs/ufs/extattr.h>
#include <ufs/ufs/quota.h>
#include <ufs/ufs/inode.h>
#include <ufs/ufs/ufsmount.h>
#include <ufs/ufs/ufs_extern.h>
#include <gnu/ext2fs/ext2_fs_sb.h>
#include <gnu/ext2fs/fs.h>
#include <gnu/ext2fs/ext2_extern.h>
#include <gnu/ext2fs/ext2_fs.h>
static int ext2_makeinode __P((int mode, struct vnode *, struct vnode **, struct componentname *));
static int ext2_fsync __P((struct vop_fsync_args *));
static int ext2_read __P((struct vop_read_args *));
static int ext2_write __P((struct vop_write_args *));
static int ext2_remove __P((struct vop_remove_args *));
static int ext2_link __P((struct vop_link_args *));
static int ext2_rename __P((struct vop_rename_args *));
static int ext2_mkdir __P((struct vop_mkdir_args *));
static int ext2_rmdir __P((struct vop_rmdir_args *));
static int ext2_create __P((struct vop_create_args *));
static int ext2_mknod __P((struct vop_mknod_args *));
static int ext2_symlink __P((struct vop_symlink_args *));
static int ext2_getpages __P((struct vop_getpages_args *));
static int ext2_putpages __P((struct vop_putpages_args *));
/* Global vfs data structures for ufs. */
vop_t **ext2_vnodeop_p;
static struct vnodeopv_entry_desc ext2_vnodeop_entries[] = {
{ &vop_default_desc, (vop_t *) ufs_vnoperate },
{ &vop_cachedlookup_desc, (vop_t *) ext2_lookup },
{ &vop_fsync_desc, (vop_t *) ext2_fsync },
{ &vop_inactive_desc, (vop_t *) ext2_inactive },
{ &vop_lookup_desc, (vop_t *) vfs_cache_lookup },
{ &vop_read_desc, (vop_t *) ext2_read },
{ &vop_readdir_desc, (vop_t *) ext2_readdir },
{ &vop_reallocblks_desc, (vop_t *) ext2_reallocblks },
{ &vop_write_desc, (vop_t *) ext2_write },
{ &vop_remove_desc, (vop_t *) ext2_remove },
{ &vop_link_desc, (vop_t *) ext2_link },
{ &vop_rename_desc, (vop_t *) ext2_rename },
{ &vop_mkdir_desc, (vop_t *) ext2_mkdir },
{ &vop_rmdir_desc, (vop_t *) ext2_rmdir },
{ &vop_create_desc, (vop_t *) ext2_create },
{ &vop_mknod_desc, (vop_t *) ext2_mknod },
{ &vop_symlink_desc, (vop_t *) ext2_symlink },
{ &vop_getpages_desc, (vop_t *) ext2_getpages },
{ &vop_putpages_desc, (vop_t *) ext2_putpages },
{ NULL, NULL }
};
static struct vnodeopv_desc ext2fs_vnodeop_opv_desc =
{ &ext2_vnodeop_p, ext2_vnodeop_entries };
vop_t **ext2_specop_p;
static struct vnodeopv_entry_desc ext2_specop_entries[] = {
{ &vop_default_desc, (vop_t *) ufs_vnoperatespec },
{ &vop_fsync_desc, (vop_t *) ext2_fsync },
{ &vop_inactive_desc, (vop_t *) ext2_inactive },
{ NULL, NULL }
};
static struct vnodeopv_desc ext2fs_specop_opv_desc =
{ &ext2_specop_p, ext2_specop_entries };
vop_t **ext2_fifoop_p;
static struct vnodeopv_entry_desc ext2_fifoop_entries[] = {
{ &vop_default_desc, (vop_t *) ufs_vnoperatefifo },
{ &vop_fsync_desc, (vop_t *) ext2_fsync },
{ &vop_inactive_desc, (vop_t *) ext2_inactive },
{ NULL, NULL }
};
static struct vnodeopv_desc ext2fs_fifoop_opv_desc =
{ &ext2_fifoop_p, ext2_fifoop_entries };
VNODEOP_SET(ext2fs_vnodeop_opv_desc);
VNODEOP_SET(ext2fs_specop_opv_desc);
VNODEOP_SET(ext2fs_fifoop_opv_desc);
#include <gnu/ext2fs/ext2_readwrite.c>
/*
* A virgin directory (no blushing please).
* Note that the type and namlen fields are reversed relative to ufs.
* Also, we don't use `struct odirtemplate', since it would just cause
* endianness problems.
*/
static struct dirtemplate mastertemplate = {
0, 12, 1, EXT2_FT_DIR, ".",
0, DIRBLKSIZ - 12, 2, EXT2_FT_DIR, ".."
};
static struct dirtemplate omastertemplate = {
0, 12, 1, EXT2_FT_UNKNOWN, ".",
0, DIRBLKSIZ - 12, 2, EXT2_FT_UNKNOWN, ".."
};
/*
* Create a regular file
*/
static int
ext2_create(ap)
struct vop_create_args /* {
struct vnode *a_dvp;
struct vnode **a_vpp;
struct componentname *a_cnp;
struct vattr *a_vap;
} */ *ap;
{
int error;
error =
ext2_makeinode(MAKEIMODE(ap->a_vap->va_type, ap->a_vap->va_mode),
ap->a_dvp, ap->a_vpp, ap->a_cnp);
if (error)
return (error);
return (0);
}
/*
* Synch an open file.
*/
/* ARGSUSED */
static int
ext2_fsync(ap)
struct vop_fsync_args /* {
struct vnode *a_vp;
struct ucred *a_cred;
int a_waitfor;
struct proc *a_p;
} */ *ap;
{
register struct vnode *vp = ap->a_vp;
register struct buf *bp;
struct buf *nbp;
int s;
/*
* XXX why is all this fs specific?
*/
/*
* Flush all dirty buffers associated with a vnode.
*/
ext2_discard_prealloc(VTOI(vp));
loop:
s = splbio();
for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
nbp = TAILQ_NEXT(bp, b_vnbufs);
if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT))
continue;
if ((bp->b_flags & B_DELWRI) == 0)
panic("ext2_fsync: not dirty");
bremfree(bp);
splx(s);
/*
* Wait for I/O associated with indirect blocks to complete,
* since there is no way to quickly wait for them below.
*/
if (bp->b_vp == vp || ap->a_waitfor == MNT_NOWAIT)
(void) bawrite(bp);
else
(void) bwrite(bp);
goto loop;
}
if (ap->a_waitfor == MNT_WAIT) {
while (vp->v_numoutput) {
vp->v_flag |= VBWAIT;
tsleep(&vp->v_numoutput, PRIBIO + 1, "e2fsyn", 0);
}
#if DIAGNOSTIC
if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) {
vprint("ext2_fsync: dirty", vp);
goto loop;
}
#endif
}
splx(s);
return (UFS_UPDATE(ap->a_vp, ap->a_waitfor == MNT_WAIT));
}
/*
* Mknod vnode call
*/
/* ARGSUSED */
static int
ext2_mknod(ap)
struct vop_mknod_args /* {
struct vnode *a_dvp;
struct vnode **a_vpp;
struct componentname *a_cnp;
struct vattr *a_vap;
} */ *ap;
{
struct vattr *vap = ap->a_vap;
struct vnode **vpp = ap->a_vpp;
struct inode *ip;
ino_t ino;
int error;
error = ext2_makeinode(MAKEIMODE(vap->va_type, vap->va_mode),
ap->a_dvp, vpp, ap->a_cnp);
if (error)
return (error);
ip = VTOI(*vpp);
ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE;
if (vap->va_rdev != VNOVAL) {
/*
* Want to be able to use this to make badblock
* inodes, so don't truncate the dev number.
*/
ip->i_rdev = vap->va_rdev;
}
/*
* Remove inode, then reload it through VFS_VGET so it is
* checked to see if it is an alias of an existing entry in
* the inode cache.
*/
vput(*vpp);
(*vpp)->v_type = VNON;
ino = ip->i_number; /* Save this before vgone() invalidates ip. */
vgone(*vpp);
error = VFS_VGET(ap->a_dvp->v_mount, ino, vpp);
if (error) {
*vpp = NULL;
return (error);
}
return (0);
}
static int
ext2_remove(ap)
struct vop_remove_args /* {
struct vnode *a_dvp;
struct vnode *a_vp;
struct componentname *a_cnp;
} */ *ap;
{
struct inode *ip;
struct vnode *vp = ap->a_vp;
struct vnode *dvp = ap->a_dvp;
int error;
ip = VTOI(vp);
if ((ip->i_flags & (NOUNLINK | IMMUTABLE | APPEND)) ||
(VTOI(dvp)->i_flags & APPEND)) {
error = EPERM;
goto out;
}
error = ext2_dirremove(dvp, ap->a_cnp);
if (error == 0) {
ip->i_nlink--;
ip->i_flag |= IN_CHANGE;
}
out:
return (error);
}
/*
* link vnode call
*/
static int
ext2_link(ap)
struct vop_link_args /* {
struct vnode *a_tdvp;
struct vnode *a_vp;
struct componentname *a_cnp;
} */ *ap;
{
struct vnode *vp = ap->a_vp;
struct vnode *tdvp = ap->a_tdvp;
struct componentname *cnp = ap->a_cnp;
struct proc *p = cnp->cn_proc;
struct inode *ip;
int error;
#ifdef DIAGNOSTIC
if ((cnp->cn_flags & HASBUF) == 0)
panic("ufs_link: no name");
#endif
if (tdvp->v_mount != vp->v_mount) {
error = EXDEV;
goto out2;
}
if (tdvp != vp && (error = vn_lock(vp, LK_EXCLUSIVE, p))) {
goto out2;
}
ip = VTOI(vp);
if ((nlink_t)ip->i_nlink >= LINK_MAX) {
error = EMLINK;
goto out1;
}
if (ip->i_flags & (IMMUTABLE | APPEND)) {
error = EPERM;
goto out1;
}
ip->i_nlink++;
ip->i_flag |= IN_CHANGE;
error = UFS_UPDATE(vp, 1);
if (!error)
error = ext2_direnter(ip, tdvp, cnp);
if (error) {
ip->i_nlink--;
ip->i_flag |= IN_CHANGE;
}
out1:
if (tdvp != vp)
VOP_UNLOCK(vp, 0, p);
out2:
return (error);
}
/*
* Rename system call.
* See comments in sys/ufs/ufs/ufs_vnops.c
*/
static int
ext2_rename(ap)
struct vop_rename_args /* {
struct vnode *a_fdvp;
struct vnode *a_fvp;
struct componentname *a_fcnp;
struct vnode *a_tdvp;
struct vnode *a_tvp;
struct componentname *a_tcnp;
} */ *ap;
{
struct vnode *tvp = ap->a_tvp;
register struct vnode *tdvp = ap->a_tdvp;
struct vnode *fvp = ap->a_fvp;
struct vnode *fdvp = ap->a_fdvp;
struct componentname *tcnp = ap->a_tcnp;
struct componentname *fcnp = ap->a_fcnp;
struct proc *p = fcnp->cn_proc;
struct inode *ip, *xp, *dp;
struct dirtemplate dirbuf;
int doingdirectory = 0, oldparent = 0, newparent = 0;
int error = 0;
u_char namlen;
#ifdef DIAGNOSTIC
if ((tcnp->cn_flags & HASBUF) == 0 ||
(fcnp->cn_flags & HASBUF) == 0)
panic("ufs_rename: no name");
#endif
/*
* Check for cross-device rename.
*/
if ((fvp->v_mount != tdvp->v_mount) ||
(tvp && (fvp->v_mount != tvp->v_mount))) {
error = EXDEV;
abortit:
if (tdvp == tvp)
vrele(tdvp);
else
vput(tdvp);
if (tvp)
vput(tvp);
vrele(fdvp);
vrele(fvp);
return (error);
}
if (tvp && ((VTOI(tvp)->i_flags & (NOUNLINK | IMMUTABLE | APPEND)) ||
(VTOI(tdvp)->i_flags & APPEND))) {
error = EPERM;
goto abortit;
}
/*
* Check if just deleting a link name or if we've lost a race.
* If another process completes the same rename after we've looked
* up the source and have blocked looking up the target, then the
* source and target inodes may be identical now although the
* names were never linked.
*/
if (fvp == tvp) {
if (fvp->v_type == VDIR) {
/*
* Linked directories are impossible, so we must
* have lost the race. Pretend that the rename
* completed before the lookup.
*/
#ifdef UFS_RENAME_DEBUG
printf("ufs_rename: fvp == tvp for directories\n");
#endif
error = ENOENT;
goto abortit;
}
/* Release destination completely. */
vput(tdvp);
vput(tvp);
/*
* Delete source. There is another race now that everything
* is unlocked, but this doesn't cause any new complications.
* Relookup() may find a file that is unrelated to the
* original one, or it may fail. Too bad.
*/
vrele(fdvp);
vrele(fvp);
fcnp->cn_flags &= ~MODMASK;
fcnp->cn_flags |= LOCKPARENT | LOCKLEAF;
fcnp->cn_nameiop = DELETE;
VREF(fdvp);
error = relookup(fdvp, &fvp, fcnp);
if (error == 0)
vrele(fdvp);
if (fvp == NULL) {
#ifdef UFS_RENAME_DEBUG
printf("ufs_rename: from name disappeared\n");
#endif
return (ENOENT);
}
error = VOP_REMOVE(fdvp, fvp, fcnp);
if (fdvp == fvp)
vrele(fdvp);
else
vput(fdvp);
if (fvp != NULLVP)
vput(fvp);
return (error);
}
if ((error = vn_lock(fvp, LK_EXCLUSIVE, p)) != 0)
goto abortit;
dp = VTOI(fdvp);
ip = VTOI(fvp);
if (ip->i_nlink >= LINK_MAX) {
VOP_UNLOCK(fvp, 0, p);
error = EMLINK;
goto abortit;
}
if ((ip->i_flags & (NOUNLINK | IMMUTABLE | APPEND))
|| (dp->i_flags & APPEND)) {
VOP_UNLOCK(fvp, 0, p);
error = EPERM;
goto abortit;
}
if ((ip->i_mode & IFMT) == IFDIR) {
/*
* Avoid ".", "..", and aliases of "." for obvious reasons.
*/
if ((fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.') ||
dp == ip || (fcnp->cn_flags | tcnp->cn_flags) & ISDOTDOT ||
(ip->i_flag & IN_RENAME)) {
VOP_UNLOCK(fvp, 0, p);
error = EINVAL;
goto abortit;
}
ip->i_flag |= IN_RENAME;
oldparent = dp->i_number;
doingdirectory++;
}
vrele(fdvp);
/*
* When the target exists, both the directory
* and target vnodes are returned locked.
*/
dp = VTOI(tdvp);
xp = NULL;
if (tvp)
xp = VTOI(tvp);
/*
* 1) Bump link count while we're moving stuff
* around. If we crash somewhere before
* completing our work, the link count
* may be wrong, but correctable.
*/
ip->i_nlink++;
ip->i_flag |= IN_CHANGE;
if ((error = UFS_UPDATE(fvp, 1)) != 0) {
VOP_UNLOCK(fvp, 0, p);
goto bad;
}
/*
* If ".." must be changed (ie the directory gets a new
* parent) then the source directory must not be in the
* directory heirarchy above the target, as this would
* orphan everything below the source directory. Also
* the user must have write permission in the source so
* as to be able to change "..". We must repeat the call
* to namei, as the parent directory is unlocked by the
* call to checkpath().
*/
error = VOP_ACCESS(fvp, VWRITE, tcnp->cn_cred, tcnp->cn_proc);
VOP_UNLOCK(fvp, 0, p);
if (oldparent != dp->i_number)
newparent = dp->i_number;
if (doingdirectory && newparent) {
if (error) /* write access check above */
goto bad;
if (xp != NULL)
vput(tvp);
error = ext2_checkpath(ip, dp, tcnp->cn_cred);
if (error)
goto out;
VREF(tdvp);
error = relookup(tdvp, &tvp, tcnp);
if (error)
goto out;
vrele(tdvp);
dp = VTOI(tdvp);
xp = NULL;
if (tvp)
xp = VTOI(tvp);
}
/*
* 2) If target doesn't exist, link the target
* to the source and unlink the source.
* Otherwise, rewrite the target directory
* entry to reference the source inode and
* expunge the original entry's existence.
*/
if (xp == NULL) {
if (dp->i_dev != ip->i_dev)
panic("ufs_rename: EXDEV");
/*
* Account for ".." in new directory.
* When source and destination have the same
* parent we don't fool with the link count.
*/
if (doingdirectory && newparent) {
if ((nlink_t)dp->i_nlink >= LINK_MAX) {
error = EMLINK;
goto bad;
}
dp->i_nlink++;
dp->i_flag |= IN_CHANGE;
error = UFS_UPDATE(tdvp, 1);
if (error)
goto bad;
}
error = ext2_direnter(ip, tdvp, tcnp);
if (error) {
if (doingdirectory && newparent) {
dp->i_nlink--;
dp->i_flag |= IN_CHANGE;
(void)UFS_UPDATE(tdvp, 1);
}
goto bad;
}
vput(tdvp);
} else {
if (xp->i_dev != dp->i_dev || xp->i_dev != ip->i_dev)
panic("ufs_rename: EXDEV");
/*
* Short circuit rename(foo, foo).
*/
if (xp->i_number == ip->i_number)
panic("ufs_rename: same file");
/*
* If the parent directory is "sticky", then the user must
* own the parent directory, or the destination of the rename,
* otherwise the destination may not be changed (except by
* root). This implements append-only directories.
*/
if ((dp->i_mode & S_ISTXT) && tcnp->cn_cred->cr_uid != 0 &&
tcnp->cn_cred->cr_uid != dp->i_uid &&
xp->i_uid != tcnp->cn_cred->cr_uid) {
error = EPERM;
goto bad;
}
/*
* Target must be empty if a directory and have no links
* to it. Also, ensure source and target are compatible
* (both directories, or both not directories).
*/
if ((xp->i_mode&IFMT) == IFDIR) {
if (! ext2_dirempty(xp, dp->i_number, tcnp->cn_cred) ||
xp->i_nlink > 2) {
error = ENOTEMPTY;
goto bad;
}
if (!doingdirectory) {
error = ENOTDIR;
goto bad;
}
cache_purge(tdvp);
} else if (doingdirectory) {
error = EISDIR;
goto bad;
}
error = ext2_dirrewrite(dp, ip, tcnp);
if (error)
goto bad;
/*
* If the target directory is in the same
* directory as the source directory,
* decrement the link count on the parent
* of the target directory.
*/
if (doingdirectory && !newparent) {
dp->i_nlink--;
dp->i_flag |= IN_CHANGE;
}
vput(tdvp);
/*
* Adjust the link count of the target to
* reflect the dirrewrite above. If this is
* a directory it is empty and there are
* no links to it, so we can squash the inode and
* any space associated with it. We disallowed
* renaming over top of a directory with links to
* it above, as the remaining link would point to
* a directory without "." or ".." entries.
*/
xp->i_nlink--;
if (doingdirectory) {
if (--xp->i_nlink != 0)
panic("ufs_rename: linked directory");
error = UFS_TRUNCATE(tvp, (off_t)0, IO_SYNC,
tcnp->cn_cred, tcnp->cn_proc);
}
xp->i_flag |= IN_CHANGE;
vput(tvp);
xp = NULL;
}
/*
* 3) Unlink the source.
*/
fcnp->cn_flags &= ~MODMASK;
fcnp->cn_flags |= LOCKPARENT | LOCKLEAF;
VREF(fdvp);
error = relookup(fdvp, &fvp, fcnp);
if (error == 0)
vrele(fdvp);
if (fvp != NULL) {
xp = VTOI(fvp);
dp = VTOI(fdvp);
} else {
/*
* From name has disappeared.
*/
if (doingdirectory)
panic("ufs_rename: lost dir entry");
vrele(ap->a_fvp);
return (0);
}
/*
* Ensure that the directory entry still exists and has not
* changed while the new name has been entered. If the source is
* a file then the entry may have been unlinked or renamed. In
* either case there is no further work to be done. If the source
* is a directory then it cannot have been rmdir'ed; its link
* count of three would cause a rmdir to fail with ENOTEMPTY.
* The IN_RENAME flag ensures that it cannot be moved by another
* rename.
*/
if (xp != ip) {
if (doingdirectory)
panic("ufs_rename: lost dir entry");
} else {
/*
* If the source is a directory with a
* new parent, the link count of the old
* parent directory must be decremented
* and ".." set to point to the new parent.
*/
if (doingdirectory && newparent) {
dp->i_nlink--;
dp->i_flag |= IN_CHANGE;
error = vn_rdwr(UIO_READ, fvp, (caddr_t)&dirbuf,
sizeof (struct dirtemplate), (off_t)0,
UIO_SYSSPACE, IO_NODELOCKED,
tcnp->cn_cred, (int *)0, (struct proc *)0);
if (error == 0) {
/* Like ufs little-endian: */
namlen = dirbuf.dotdot_type;
if (namlen != 2 ||
dirbuf.dotdot_name[0] != '.' ||
dirbuf.dotdot_name[1] != '.') {
ufs_dirbad(xp, (doff_t)12,
"rename: mangled dir");
} else {
dirbuf.dotdot_ino = newparent;
(void) vn_rdwr(UIO_WRITE, fvp,
(caddr_t)&dirbuf,
sizeof (struct dirtemplate),
(off_t)0, UIO_SYSSPACE,
IO_NODELOCKED|IO_SYNC,
tcnp->cn_cred, (int *)0,
(struct proc *)0);
cache_purge(fdvp);
}
}
}
error = ext2_dirremove(fdvp, fcnp);
if (!error) {
xp->i_nlink--;
xp->i_flag |= IN_CHANGE;
}
xp->i_flag &= ~IN_RENAME;
}
if (dp)
vput(fdvp);
if (xp)
vput(fvp);
vrele(ap->a_fvp);
return (error);
bad:
if (xp)
vput(ITOV(xp));
vput(ITOV(dp));
out:
if (doingdirectory)
ip->i_flag &= ~IN_RENAME;
if (vn_lock(fvp, LK_EXCLUSIVE, p) == 0) {
ip->i_nlink--;
ip->i_flag |= IN_CHANGE;
ip->i_flag &= ~IN_RENAME;
vput(fvp);
} else
vrele(fvp);
return (error);
}
/*
* Mkdir system call
*/
static int
ext2_mkdir(ap)
struct vop_mkdir_args /* {
struct vnode *a_dvp;
struct vnode **a_vpp;
struct componentname *a_cnp;
struct vattr *a_vap;
} */ *ap;
{
register struct vnode *dvp = ap->a_dvp;
register struct vattr *vap = ap->a_vap;
register struct componentname *cnp = ap->a_cnp;
register struct inode *ip, *dp;
struct vnode *tvp;
struct dirtemplate dirtemplate, *dtp;
int error, dmode;
#ifdef DIAGNOSTIC
if ((cnp->cn_flags & HASBUF) == 0)
panic("ufs_mkdir: no name");
#endif
dp = VTOI(dvp);
if ((nlink_t)dp->i_nlink >= LINK_MAX) {
error = EMLINK;
goto out;
}
dmode = vap->va_mode & 0777;
dmode |= IFDIR;
/*
* Must simulate part of ext2_makeinode here to acquire the inode,
* but not have it entered in the parent directory. The entry is
* made later after writing "." and ".." entries.
*/
error = UFS_VALLOC(dvp, dmode, cnp->cn_cred, &tvp);
if (error)
goto out;
ip = VTOI(tvp);
ip->i_gid = dp->i_gid;
#ifdef SUIDDIR
{
#ifdef QUOTA
struct ucred ucred, *ucp;
ucp = cnp->cn_cred;
#endif I
/*
* if we are hacking owners here, (only do this where told to)
* and we are not giving it TOO root, (would subvert quotas)
* then go ahead and give it to the other user.
* The new directory also inherits the SUID bit.
* If user's UID and dir UID are the same,
* 'give it away' so that the SUID is still forced on.
*/
if ( (dvp->v_mount->mnt_flag & MNT_SUIDDIR) &&
(dp->i_mode & ISUID) && dp->i_uid) {
dmode |= ISUID;
ip->i_uid = dp->i_uid;
#ifdef QUOTA
if (dp->i_uid != cnp->cn_cred->cr_uid) {
/*
* make sure the correct user gets charged
* for the space.
* Make a dummy credential for the victim.
* XXX This seems to never be accessed out of
* our context so a stack variable is ok.
*/
ucred.cr_ref = 1;
ucred.cr_uid = ip->i_uid;
ucred.cr_ngroups = 1;
ucred.cr_groups[0] = dp->i_gid;
ucp = &ucred;
}
#endif I
} else {
ip->i_uid = cnp->cn_cred->cr_uid;
}
#ifdef QUOTA
if ((error = getinoquota(ip)) ||
(error = chkiq(ip, 1, ucp, 0))) {
UFS_VFREE(tvp, ip->i_number, dmode);
vput(tvp);
return (error);
}
#endif
}
#else
ip->i_uid = cnp->cn_cred->cr_uid;
#ifdef QUOTA
if ((error = getinoquota(ip)) ||
(error = chkiq(ip, 1, cnp->cn_cred, 0))) {
UFS_VFREE(tvp, ip->i_number, dmode);
vput(tvp);
return (error);
}
#endif
#endif
ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE;
ip->i_mode = dmode;
tvp->v_type = VDIR; /* Rest init'd in getnewvnode(). */
ip->i_nlink = 2;
if (cnp->cn_flags & ISWHITEOUT)
ip->i_flags |= UF_OPAQUE;
error = UFS_UPDATE(tvp, 1);
/*
* Bump link count in parent directory
* to reflect work done below. Should
* be done before reference is created
* so reparation is possible if we crash.
*/
dp->i_nlink++;
dp->i_flag |= IN_CHANGE;
error = UFS_UPDATE(dvp, 1);
if (error)
goto bad;
/* Initialize directory with "." and ".." from static template. */
if (EXT2_HAS_INCOMPAT_FEATURE(ip->i_e2fs->s_es,
EXT2_FEATURE_INCOMPAT_FILETYPE))
dtp = &mastertemplate;
else
dtp = &omastertemplate;
dirtemplate = *dtp;
dirtemplate.dot_ino = ip->i_number;
dirtemplate.dotdot_ino = dp->i_number;
/* note that in ext2 DIRBLKSIZ == blocksize, not DEV_BSIZE
* so let's just redefine it - for this function only
*/
#undef DIRBLKSIZ
#define DIRBLKSIZ VTOI(dvp)->i_e2fs->s_blocksize
dirtemplate.dotdot_reclen = DIRBLKSIZ - 12;
error = vn_rdwr(UIO_WRITE, tvp, (caddr_t)&dirtemplate,
sizeof (dirtemplate), (off_t)0, UIO_SYSSPACE,
IO_NODELOCKED|IO_SYNC, cnp->cn_cred, (int *)0, (struct proc *)0);
if (error) {
dp->i_nlink--;
dp->i_flag |= IN_CHANGE;
goto bad;
}
if (DIRBLKSIZ > VFSTOUFS(dvp->v_mount)->um_mountp->mnt_stat.f_bsize)
panic("ufs_mkdir: blksize"); /* XXX should grow with balloc() */
else {
ip->i_size = DIRBLKSIZ;
ip->i_flag |= IN_CHANGE;
}
/* Directory set up, now install its entry in the parent directory. */
error = ext2_direnter(ip, dvp, cnp);
if (error) {
dp->i_nlink--;
dp->i_flag |= IN_CHANGE;
}
bad:
/*
* No need to do an explicit VOP_TRUNCATE here, vrele will do this
* for us because we set the link count to 0.
*/
if (error) {
ip->i_nlink = 0;
ip->i_flag |= IN_CHANGE;
vput(tvp);
} else
*ap->a_vpp = tvp;
out:
return (error);
#undef DIRBLKSIZ
#define DIRBLKSIZ DEV_BSIZE
}
/*
* Rmdir system call.
*/
static int
ext2_rmdir(ap)
struct vop_rmdir_args /* {
struct vnode *a_dvp;
struct vnode *a_vp;
struct componentname *a_cnp;
} */ *ap;
{
struct vnode *vp = ap->a_vp;
struct vnode *dvp = ap->a_dvp;
struct componentname *cnp = ap->a_cnp;
struct proc *p = cnp->cn_proc;
struct inode *ip, *dp;
int error;
ip = VTOI(vp);
dp = VTOI(dvp);
/*
* Verify the directory is empty (and valid).
* (Rmdir ".." won't be valid since
* ".." will contain a reference to
* the current directory and thus be
* non-empty.)
*/
error = 0;
if (ip->i_nlink != 2 || !ext2_dirempty(ip, dp->i_number, cnp->cn_cred)) {
error = ENOTEMPTY;
goto out;
}
if ((dp->i_flags & APPEND)
|| (ip->i_flags & (NOUNLINK | IMMUTABLE | APPEND))) {
error = EPERM;
goto out;
}
/*
* Delete reference to directory before purging
* inode. If we crash in between, the directory
* will be reattached to lost+found,
*/
error = ext2_dirremove(dvp, cnp);
if (error)
goto out;
dp->i_nlink--;
dp->i_flag |= IN_CHANGE;
cache_purge(dvp);
VOP_UNLOCK(dvp, 0, p);
/*
* Truncate inode. The only stuff left
* in the directory is "." and "..". The
* "." reference is inconsequential since
* we're quashing it. The ".." reference
* has already been adjusted above. We've
* removed the "." reference and the reference
* in the parent directory, but there may be
* other hard links so decrement by 2 and
* worry about them later.
*/
ip->i_nlink -= 2;
error = UFS_TRUNCATE(vp, (off_t)0, IO_SYNC, cnp->cn_cred, p);
cache_purge(ITOV(ip));
vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, p);
out:
return (error);
}
/*
* symlink -- make a symbolic link
*/
static int
ext2_symlink(ap)
struct vop_symlink_args /* {
struct vnode *a_dvp;
struct vnode **a_vpp;
struct componentname *a_cnp;
struct vattr *a_vap;
char *a_target;
} */ *ap;
{
register struct vnode *vp, **vpp = ap->a_vpp;
register struct inode *ip;
int len, error;
error = ext2_makeinode(IFLNK | ap->a_vap->va_mode, ap->a_dvp,
vpp, ap->a_cnp);
if (error)
return (error);
vp = *vpp;
len = strlen(ap->a_target);
if (len < vp->v_mount->mnt_maxsymlinklen) {
ip = VTOI(vp);
bcopy(ap->a_target, (char *)ip->i_shortlink, len);
ip->i_size = len;
ip->i_flag |= IN_CHANGE | IN_UPDATE;
} else
error = vn_rdwr(UIO_WRITE, vp, ap->a_target, len, (off_t)0,
UIO_SYSSPACE, IO_NODELOCKED, ap->a_cnp->cn_cred, (int *)0,
(struct proc *)0);
if (error)
vput(vp);
return (error);
}
/*
* Allocate a new inode.
*/
static int
ext2_makeinode(mode, dvp, vpp, cnp)
int mode;
struct vnode *dvp;
struct vnode **vpp;
struct componentname *cnp;
{
register struct inode *ip, *pdir;
struct vnode *tvp;
int error;
pdir = VTOI(dvp);
#ifdef DIAGNOSTIC
if ((cnp->cn_flags & HASBUF) == 0)
panic("ext2_makeinode: no name");
#endif
*vpp = NULL;
if ((mode & IFMT) == 0)
mode |= IFREG;
error = UFS_VALLOC(dvp, mode, cnp->cn_cred, &tvp);
if (error) {
return (error);
}
ip = VTOI(tvp);
ip->i_gid = pdir->i_gid;
#ifdef SUIDDIR
{
#ifdef QUOTA
struct ucred ucred, *ucp;
ucp = cnp->cn_cred;
#endif I
/*
* if we are
* not the owner of the directory,
* and we are hacking owners here, (only do this where told to)
* and we are not giving it TOO root, (would subvert quotas)
* then go ahead and give it to the other user.
* Note that this drops off the execute bits for security.
*/
if ( (dvp->v_mount->mnt_flag & MNT_SUIDDIR) &&
(pdir->i_mode & ISUID) &&
(pdir->i_uid != cnp->cn_cred->cr_uid) && pdir->i_uid) {
ip->i_uid = pdir->i_uid;
mode &= ~07111;
#ifdef QUOTA
/*
* make sure the correct user gets charged
* for the space.
* Quickly knock up a dummy credential for the victim.
* XXX This seems to never be accessed out of our
* context so a stack variable is ok.
*/
ucred.cr_ref = 1;
ucred.cr_uid = ip->i_uid;
ucred.cr_ngroups = 1;
ucred.cr_groups[0] = pdir->i_gid;
ucp = &ucred;
#endif I
} else {
ip->i_uid = cnp->cn_cred->cr_uid;
}
#ifdef QUOTA
if ((error = getinoquota(ip)) ||
(error = chkiq(ip, 1, ucp, 0))) {
UFS_VFREE(tvp, ip->i_number, mode);
vput(tvp);
return (error);
}
#endif
}
#else
ip->i_uid = cnp->cn_cred->cr_uid;
#ifdef QUOTA
if ((error = getinoquota(ip)) ||
(error = chkiq(ip, 1, cnp->cn_cred, 0))) {
UFS_VFREE(tvp, ip->i_number, mode);
vput(tvp);
return (error);
}
#endif
#endif
ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE;
ip->i_mode = mode;
tvp->v_type = IFTOVT(mode); /* Rest init'd in getnewvnode(). */
ip->i_nlink = 1;
if ((ip->i_mode & ISGID) && !groupmember(ip->i_gid, cnp->cn_cred) &&
suser_xxx(cnp->cn_cred, 0, PRISON_ROOT))
ip->i_mode &= ~ISGID;
if (cnp->cn_flags & ISWHITEOUT)
ip->i_flags |= UF_OPAQUE;
/*
* Make sure inode goes to disk before directory entry.
*/
error = UFS_UPDATE(tvp, 1);
if (error)
goto bad;
error = ext2_direnter(ip, dvp, cnp);
if (error)
goto bad;
*vpp = tvp;
return (0);
bad:
/*
* Write error occurred trying to update the inode
* or the directory so must deallocate the inode.
*/
ip->i_nlink = 0;
ip->i_flag |= IN_CHANGE;
vput(tvp);
return (error);
}
/*
* get page routine
*
* XXX By default, wimp out... note that a_offset is ignored (and always
* XXX has been).
*/
static int
ext2_getpages(ap)
struct vop_getpages_args *ap;
{
return (vnode_pager_generic_getpages(ap->a_vp, ap->a_m, ap->a_count,
ap->a_reqpage));
}
/*
* put page routine
*
* XXX By default, wimp out... note that a_offset is ignored (and always
* XXX has been).
*/
static int
ext2_putpages(ap)
struct vop_putpages_args *ap;
{
return (vnode_pager_generic_putpages(ap->a_vp, ap->a_m, ap->a_count,
ap->a_sync, ap->a_rtvals));
}
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