1 files changed, 137 insertions, 168 deletions

diff --git a/fs/xfs/linux-2.6/xfs_ioctl.c b/fs/xfs/linux-2.6/xfs_ioctl.c
index e5be1e0be802..4bd112313f33 100644
--- a/fs/xfs/linux-2.6/xfs_ioctl.c
+++ b/fs/xfs/linux-2.6/xfs_ioctl.c
@@ -50,12 +50,14 @@
 #include "xfs_vnodeops.h"
 #include "xfs_quota.h"
 #include "xfs_inode_item.h"
+#include "xfs_export.h"
 
 #include <linux/capability.h>
 #include <linux/dcache.h>
 #include <linux/mount.h>
 #include <linux/namei.h>
 #include <linux/pagemap.h>
+#include <linux/exportfs.h>
 
 /*
  * xfs_find_handle maps from userspace xfs_fsop_handlereq structure to
@@ -164,97 +166,69 @@ xfs_find_handle(
         return 0;
 }
 
-
 /*
- * Convert userspace handle data into inode.
- *
- * We use the fact that all the fsop_handlereq ioctl calls have a data
- * structure argument whose first component is always a xfs_fsop_handlereq_t,
- * so we can pass that sub structure into this handy, shared routine.
- *
- * If no error, caller must always iput the returned inode.
+ * No need to do permission checks on the various pathname components
+ * as the handle operations are privileged.
  */
 STATIC int
-xfs_vget_fsop_handlereq(
-        xfs_mount_t             *mp,
-        struct inode            *parinode,      /* parent inode pointer    */
-        xfs_fsop_handlereq_t    *hreq,
-        struct inode            **inode)
+xfs_handle_acceptable(
+        void                    *context,
+        struct dentry           *dentry)
+{
+        return 1;
+}
+
+/*
+ * Convert userspace handle data into a dentry.
+ */
+struct dentry *
+xfs_handle_to_dentry(
+        struct file             *parfilp,
+        void __user             *uhandle,
+        u32                     hlen)
 {
-        void                    __user *hanp;
-        size_t                  hlen;
-        xfs_fid_t               *xfid;
-        xfs_handle_t            *handlep;
         xfs_handle_t            handle;
-        xfs_inode_t             *ip;
-        xfs_ino_t               ino;
-        __u32                   igen;
-        int                     error;
+        struct xfs_fid64        fid;
 
         /*
          * Only allow handle opens under a directory.
          */
-        if (!S_ISDIR(parinode->i_mode))
-                return XFS_ERROR(ENOTDIR);
-
-        hanp = hreq->ihandle;
-        hlen = hreq->ihandlen;
-        handlep = &handle;
-
-        if (hlen < sizeof(handlep->ha_fsid) || hlen > sizeof(*handlep))
-                return XFS_ERROR(EINVAL);
-        if (copy_from_user(handlep, hanp, hlen))
-                return XFS_ERROR(EFAULT);
-        if (hlen < sizeof(*handlep))
-                memset(((char *)handlep) + hlen, 0, sizeof(*handlep) - hlen);
-        if (hlen > sizeof(handlep->ha_fsid)) {
-                if (handlep->ha_fid.fid_len !=
-                    (hlen - sizeof(handlep->ha_fsid) -
-                            sizeof(handlep->ha_fid.fid_len)) ||
-                    handlep->ha_fid.fid_pad)
-                        return XFS_ERROR(EINVAL);
-        }
-
-        /*
-         * Crack the handle, obtain the inode # & generation #
-         */
-        xfid = (struct xfs_fid *)&handlep->ha_fid;
-        if (xfid->fid_len == sizeof(*xfid) - sizeof(xfid->fid_len)) {
-                ino  = xfid->fid_ino;
-                igen = xfid->fid_gen;
-        } else {
-                return XFS_ERROR(EINVAL);
-        }
-
-        /*
-         * Get the XFS inode, building a Linux inode to go with it.
-         */
-        error = xfs_iget(mp, NULL, ino, 0, XFS_ILOCK_SHARED, &ip, 0);
-        if (error)
-                return error;
-        if (ip == NULL)
-                return XFS_ERROR(EIO);
-        if (ip->i_d.di_gen != igen) {
-                xfs_iput_new(ip, XFS_ILOCK_SHARED);
-                return XFS_ERROR(ENOENT);
-        }
-
-        xfs_iunlock(ip, XFS_ILOCK_SHARED);
+        if (!S_ISDIR(parfilp->f_path.dentry->d_inode->i_mode))
+                return ERR_PTR(-ENOTDIR);
+
+        if (hlen != sizeof(xfs_handle_t))
+                return ERR_PTR(-EINVAL);
+        if (copy_from_user(&handle, uhandle, hlen))
+                return ERR_PTR(-EFAULT);
+        if (handle.ha_fid.fid_len !=
+            sizeof(handle.ha_fid) - sizeof(handle.ha_fid.fid_len))
+                return ERR_PTR(-EINVAL);
+
+        memset(&fid, 0, sizeof(struct fid));
+        fid.ino = handle.ha_fid.fid_ino;
+        fid.gen = handle.ha_fid.fid_gen;
+
+        return exportfs_decode_fh(parfilp->f_path.mnt, (struct fid *)&fid, 3,
+                        FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG,
+                        xfs_handle_acceptable, NULL);
+}
 
-        *inode = VFS_I(ip);
-        return 0;
+STATIC struct dentry *
+xfs_handlereq_to_dentry(
+        struct file             *parfilp,
+        xfs_fsop_handlereq_t    *hreq)
+{
+        return xfs_handle_to_dentry(parfilp, hreq->ihandle, hreq->ihandlen);
 }
 
 int
 xfs_open_by_handle(
-        xfs_mount_t             *mp,
-        xfs_fsop_handlereq_t    *hreq,
         struct file             *parfilp,
-        struct inode            *parinode)
+        xfs_fsop_handlereq_t    *hreq)
 {
         const struct cred       *cred = current_cred();
         int                     error;
-        int                     new_fd;
+        int                     fd;
         int                     permflag;
         struct file             *filp;
         struct inode            *inode;
@@ -263,19 +237,21 @@ xfs_open_by_handle(
         if (!capable(CAP_SYS_ADMIN))
                 return -XFS_ERROR(EPERM);
 
-        error = xfs_vget_fsop_handlereq(mp, parinode, hreq, &inode);
-        if (error)
-                return -error;
+        dentry = xfs_handlereq_to_dentry(parfilp, hreq);
+        if (IS_ERR(dentry))
+                return PTR_ERR(dentry);
+        inode = dentry->d_inode;
 
         /* Restrict xfs_open_by_handle to directories & regular files. */
         if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode))) {
-                iput(inode);
-                return -XFS_ERROR(EINVAL);
+                error = -XFS_ERROR(EPERM);
+                goto out_dput;
         }
 
 #if BITS_PER_LONG != 32
         hreq->oflags |= O_LARGEFILE;
 #endif
+
         /* Put open permission in namei format. */
         permflag = hreq->oflags;
         if ((permflag+1) & O_ACCMODE)
@@ -285,50 +261,45 @@ xfs_open_by_handle(
 
         if ((!(permflag & O_APPEND) || (permflag & O_TRUNC)) &&
             (permflag & FMODE_WRITE) && IS_APPEND(inode)) {
-                iput(inode);
-                return -XFS_ERROR(EPERM);
+                error = -XFS_ERROR(EPERM);
+                goto out_dput;
         }
 
         if ((permflag & FMODE_WRITE) && IS_IMMUTABLE(inode)) {
-                iput(inode);
-                return -XFS_ERROR(EACCES);
+                error = -XFS_ERROR(EACCES);
+                goto out_dput;
         }
 
         /* Can't write directories. */
-        if ( S_ISDIR(inode->i_mode) && (permflag & FMODE_WRITE)) {
-                iput(inode);
-                return -XFS_ERROR(EISDIR);
+        if (S_ISDIR(inode->i_mode) && (permflag & FMODE_WRITE)) {
+                error = -XFS_ERROR(EISDIR);
+                goto out_dput;
         }
 
-        if ((new_fd = get_unused_fd()) < 0) {
-                iput(inode);
-                return new_fd;
+        fd = get_unused_fd();
+        if (fd < 0) {
+                error = fd;
+                goto out_dput;
         }
 
-        dentry = d_obtain_alias(inode);
-        if (IS_ERR(dentry)) {
-                put_unused_fd(new_fd);
-                return PTR_ERR(dentry);
-        }
-
-        /* Ensure umount returns EBUSY on umounts while this file is open. */
-        mntget(parfilp->f_path.mnt);
-
-        /* Create file pointer. */
-        filp = dentry_open(dentry, parfilp->f_path.mnt, hreq->oflags, cred);
+        filp = dentry_open(dentry, mntget(parfilp->f_path.mnt),
+                           hreq->oflags, cred);
         if (IS_ERR(filp)) {
-                put_unused_fd(new_fd);
-                return -XFS_ERROR(-PTR_ERR(filp));
+                put_unused_fd(fd);
+                return PTR_ERR(filp);
         }
 
         if (inode->i_mode & S_IFREG) {
-                /* invisible operation should not change atime */
                 filp->f_flags |= O_NOATIME;
                 filp->f_mode |= FMODE_NOCMTIME;
         }
 
-        fd_install(new_fd, filp);
-        return new_fd;
+        fd_install(fd, filp);
+        return fd;
+
+ out_dput:
+        dput(dentry);
+        return error;
 }
 
 /*
@@ -359,11 +330,10 @@ do_readlink(
 
 int
 xfs_readlink_by_handle(
-        xfs_mount_t             *mp,
-        xfs_fsop_handlereq_t    *hreq,
-        struct inode            *parinode)
+        struct file             *parfilp,
+        xfs_fsop_handlereq_t    *hreq)
 {
-        struct inode            *inode;
+        struct dentry           *dentry;
         __u32                   olen;
         void                    *link;
         int                     error;
@@ -371,26 +341,28 @@ xfs_readlink_by_handle(
         if (!capable(CAP_SYS_ADMIN))
                 return -XFS_ERROR(EPERM);
 
-        error = xfs_vget_fsop_handlereq(mp, parinode, hreq, &inode);
-        if (error)
-                return -error;
+        dentry = xfs_handlereq_to_dentry(parfilp, hreq);
+        if (IS_ERR(dentry))
+                return PTR_ERR(dentry);
 
         /* Restrict this handle operation to symlinks only. */
-        if (!S_ISLNK(inode->i_mode)) {
+        if (!S_ISLNK(dentry->d_inode->i_mode)) {
                 error = -XFS_ERROR(EINVAL);
-                goto out_iput;
+                goto out_dput;
         }
 
         if (copy_from_user(&olen, hreq->ohandlen, sizeof(__u32))) {
                 error = -XFS_ERROR(EFAULT);
-                goto out_iput;
+                goto out_dput;
         }
 
         link = kmalloc(MAXPATHLEN+1, GFP_KERNEL);
-        if (!link)
-                goto out_iput;
+        if (!link) {
+                error = -XFS_ERROR(ENOMEM);
+                goto out_dput;
+        }
 
-        error = -xfs_readlink(XFS_I(inode), link);
+        error = -xfs_readlink(XFS_I(dentry->d_inode), link);
         if (error)
                 goto out_kfree;
         error = do_readlink(hreq->ohandle, olen, link);
@@ -399,32 +371,31 @@ xfs_readlink_by_handle(
 
  out_kfree:
         kfree(link);
- out_iput:
-        iput(inode);
+ out_dput:
+        dput(dentry);
         return error;
 }
 
 STATIC int
 xfs_fssetdm_by_handle(
-        xfs_mount_t             *mp,
-        void                    __user *arg,
-        struct inode            *parinode)
+        struct file             *parfilp,
+        void                    __user *arg)
 {
         int                     error;
         struct fsdmidata        fsd;
         xfs_fsop_setdm_handlereq_t dmhreq;
-        struct inode            *inode;
+        struct dentry           *dentry;
 
         if (!capable(CAP_MKNOD))
                 return -XFS_ERROR(EPERM);
         if (copy_from_user(&dmhreq, arg, sizeof(xfs_fsop_setdm_handlereq_t)))
                 return -XFS_ERROR(EFAULT);
 
-        error = xfs_vget_fsop_handlereq(mp, parinode, &dmhreq.hreq, &inode);
-        if (error)
-                return -error;
+        dentry = xfs_handlereq_to_dentry(parfilp, &dmhreq.hreq);
+        if (IS_ERR(dentry))
+                return PTR_ERR(dentry);
 
-        if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) {
+        if (IS_IMMUTABLE(dentry->d_inode) || IS_APPEND(dentry->d_inode)) {
                 error = -XFS_ERROR(EPERM);
                 goto out;
         }
@@ -434,24 +405,23 @@ xfs_fssetdm_by_handle(
                 goto out;
         }
 
-        error = -xfs_set_dmattrs(XFS_I(inode), fsd.fsd_dmevmask,
+        error = -xfs_set_dmattrs(XFS_I(dentry->d_inode), fsd.fsd_dmevmask,
                                  fsd.fsd_dmstate);
 
  out:
-        iput(inode);
+        dput(dentry);
         return error;
 }
 
 STATIC int
 xfs_attrlist_by_handle(
-        xfs_mount_t             *mp,
-        void                    __user *arg,
-        struct inode            *parinode)
+        struct file             *parfilp,
+        void                    __user *arg)
 {
-        int                     error;
+        int                     error = -ENOMEM;
         attrlist_cursor_kern_t  *cursor;
         xfs_fsop_attrlist_handlereq_t al_hreq;
-        struct inode            *inode;
+        struct dentry           *dentry;
         char                    *kbuf;
 
         if (!capable(CAP_SYS_ADMIN))
@@ -467,16 +437,16 @@ xfs_attrlist_by_handle(
         if (al_hreq.flags & ~(ATTR_ROOT | ATTR_SECURE))
                 return -XFS_ERROR(EINVAL);
 
-        error = xfs_vget_fsop_handlereq(mp, parinode, &al_hreq.hreq, &inode);
-        if (error)
-                goto out;
+        dentry = xfs_handlereq_to_dentry(parfilp, &al_hreq.hreq);
+        if (IS_ERR(dentry))
+                return PTR_ERR(dentry);
 
         kbuf = kmalloc(al_hreq.buflen, GFP_KERNEL);
         if (!kbuf)
-                goto out_vn_rele;
+                goto out_dput;
 
         cursor = (attrlist_cursor_kern_t *)&al_hreq.pos;
-        error = xfs_attr_list(XFS_I(inode), kbuf, al_hreq.buflen,
+        error = -xfs_attr_list(XFS_I(dentry->d_inode), kbuf, al_hreq.buflen,
                                         al_hreq.flags, cursor);
         if (error)
                 goto out_kfree;
@@ -486,10 +456,9 @@ xfs_attrlist_by_handle(
 
  out_kfree:
         kfree(kbuf);
- out_vn_rele:
-        iput(inode);
- out:
-        return -error;
+ out_dput:
+        dput(dentry);
+        return error;
 }
 
 int
@@ -564,15 +533,13 @@ xfs_attrmulti_attr_remove(
 
 STATIC int
 xfs_attrmulti_by_handle(
-        xfs_mount_t             *mp,
-        void                    __user *arg,
         struct file             *parfilp,
-        struct inode            *parinode)
+        void                    __user *arg)
 {
         int                     error;
         xfs_attr_multiop_t      *ops;
         xfs_fsop_attrmulti_handlereq_t am_hreq;
-        struct inode            *inode;
+        struct dentry           *dentry;
         unsigned int            i, size;
         char                    *attr_name;
 
@@ -581,19 +548,19 @@ xfs_attrmulti_by_handle(
         if (copy_from_user(&am_hreq, arg, sizeof(xfs_fsop_attrmulti_handlereq_t)))
                 return -XFS_ERROR(EFAULT);
 
-        error = xfs_vget_fsop_handlereq(mp, parinode, &am_hreq.hreq, &inode);
-        if (error)
-                goto out;
+        dentry = xfs_handlereq_to_dentry(parfilp, &am_hreq.hreq);
+        if (IS_ERR(dentry))
+                return PTR_ERR(dentry);
 
         error = E2BIG;
         size = am_hreq.opcount * sizeof(xfs_attr_multiop_t);
         if (!size || size > 16 * PAGE_SIZE)
-                goto out_vn_rele;
+                goto out_dput;
 
         error = ENOMEM;
         ops = kmalloc(size, GFP_KERNEL);
         if (!ops)
-                goto out_vn_rele;
+                goto out_dput;
 
         error = EFAULT;
         if (copy_from_user(ops, am_hreq.ops, size))
@@ -615,25 +582,28 @@ xfs_attrmulti_by_handle(
 
                 switch (ops[i].am_opcode) {
                 case ATTR_OP_GET:
-                        ops[i].am_error = xfs_attrmulti_attr_get(inode,
-                                        attr_name, ops[i].am_attrvalue,
-                                        &ops[i].am_length, ops[i].am_flags);
+                        ops[i].am_error = xfs_attrmulti_attr_get(
+                                        dentry->d_inode, attr_name,
+                                        ops[i].am_attrvalue, &ops[i].am_length,
+                                        ops[i].am_flags);
                         break;
                 case ATTR_OP_SET:
                         ops[i].am_error = mnt_want_write(parfilp->f_path.mnt);
                         if (ops[i].am_error)
                                 break;
-                        ops[i].am_error = xfs_attrmulti_attr_set(inode,
-                                        attr_name, ops[i].am_attrvalue,
-                                        ops[i].am_length, ops[i].am_flags);
+                        ops[i].am_error = xfs_attrmulti_attr_set(
+                                        dentry->d_inode, attr_name,
+                                        ops[i].am_attrvalue, ops[i].am_length,
+                                        ops[i].am_flags);
                         mnt_drop_write(parfilp->f_path.mnt);
                         break;
                 case ATTR_OP_REMOVE:
                         ops[i].am_error = mnt_want_write(parfilp->f_path.mnt);
                         if (ops[i].am_error)
                                 break;
-                        ops[i].am_error = xfs_attrmulti_attr_remove(inode,
-                                        attr_name, ops[i].am_flags);
+                        ops[i].am_error = xfs_attrmulti_attr_remove(
+                                        dentry->d_inode, attr_name,
+                                        ops[i].am_flags);
                         mnt_drop_write(parfilp->f_path.mnt);
                         break;
                 default:
@@ -647,9 +617,8 @@ xfs_attrmulti_by_handle(
         kfree(attr_name);
  out_kfree_ops:
         kfree(ops);
- out_vn_rele:
-        iput(inode);
- out:
+ out_dput:
+        dput(dentry);
         return -error;
 }
 
@@ -1440,23 +1409,23 @@ xfs_file_ioctl(
 
                 if (copy_from_user(&hreq, arg, sizeof(xfs_fsop_handlereq_t)))
                         return -XFS_ERROR(EFAULT);
-                return xfs_open_by_handle(mp, &hreq, filp, inode);
+                return xfs_open_by_handle(filp, &hreq);
         }
         case XFS_IOC_FSSETDM_BY_HANDLE:
-                return xfs_fssetdm_by_handle(mp, arg, inode);
+                return xfs_fssetdm_by_handle(filp, arg);
 
         case XFS_IOC_READLINK_BY_HANDLE: {
                 xfs_fsop_handlereq_t    hreq;
 
                 if (copy_from_user(&hreq, arg, sizeof(xfs_fsop_handlereq_t)))
                         return -XFS_ERROR(EFAULT);
-                return xfs_readlink_by_handle(mp, &hreq, inode);
+                return xfs_readlink_by_handle(filp, &hreq);
         }
         case XFS_IOC_ATTRLIST_BY_HANDLE:
-                return xfs_attrlist_by_handle(mp, arg, inode);
+                return xfs_attrlist_by_handle(filp, arg);
 
         case XFS_IOC_ATTRMULTI_BY_HANDLE:
-                return xfs_attrmulti_by_handle(mp, arg, filp, inode);
+                return xfs_attrmulti_by_handle(filp, arg);
 
         case XFS_IOC_SWAPEXT: {
                 struct xfs_swapext      sxp;