xfs: always check the existence of a dirent's child inode

When we're scrubbing directory entries, we always need to iget the child
inode to make sure that the inode pointer points to a valid inode.  The
original directory scrub code (commit a5c4) only set us up to do this
for ftype=1 filesystems, which is not sufficient; and then commit 4b80
made it worse by exempting the dot and dotdot entries.

Sorta-fixes: a5c46e5e8912 ("xfs: scrub directory metadata")
Sorta-fixes: 4b80ac64450f ("xfs: scrub should mark a directory corrupt if any entries cannot be iget'd")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

diff --git a/fs/xfs/scrub/dir.c b/fs/xfs/scrub/dir.c
index 41f10e1..6404201 100644 (file)
--- a/fs/xfs/scrub/dir.c
+++ b/fs/xfs/scrub/dir.c
@@ -33,52 +33,23 @@ xchk_setup_directory(
 /* Scrub a directory entry. */
 
 /* Check that an inode's mode matches a given XFS_DIR3_FT_* type. */
-STATIC int
+STATIC void
 xchk_dir_check_ftype(
        struct xfs_scrub        *sc,
        xfs_fileoff_t           offset,
-       xfs_ino_t               inum,
+       struct xfs_inode        *ip,
        int                     ftype)
 {
        struct xfs_mount        *mp = sc->mp;
-       struct xfs_inode        *ip;
-       int                     error = 0;
 
        if (!xfs_has_ftype(mp)) {
                if (ftype != XFS_DIR3_FT_UNKNOWN && ftype != XFS_DIR3_FT_DIR)
                        xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
-               goto out;
-       }
-
-       /*
-        * Grab the inode pointed to by the dirent.  We release the
-        * inode before we cancel the scrub transaction.  Since we're
-        * don't know a priori that releasing the inode won't trigger
-        * eofblocks cleanup (which allocates what would be a nested
-        * transaction), we can't use DONTCACHE here because DONTCACHE
-        * inodes can trigger immediate inactive cleanup of the inode.
-        * Use UNTRUSTED here to check the allocation status of the inode in
-        * the inode btrees.
-        *
-        * If _iget returns -EINVAL or -ENOENT then the child inode number is
-        * garbage and the directory is corrupt.  If the _iget returns
-        * -EFSCORRUPTED or -EFSBADCRC then the child is corrupt which is a
-        *  cross referencing error.  Any other error is an operational error.
-        */
-       error = xfs_iget(mp, sc->tp, inum, XFS_IGET_UNTRUSTED, 0, &ip);
-       if (error == -EINVAL || error == -ENOENT) {
-               error = -EFSCORRUPTED;
-               xchk_fblock_process_error(sc, XFS_DATA_FORK, 0, &error);
-               goto out;
+               return;
        }
-       if (!xchk_fblock_xref_process_error(sc, XFS_DATA_FORK, offset, &error))
-               goto out;
 
        if (xfs_mode_to_ftype(VFS_I(ip)->i_mode) != ftype)
                xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
-       xfs_irele(ip);
-out:
-       return error;
 }
 
 /*
@@ -97,9 +68,9 @@ xchk_dir_actor(
        void                    *priv)
 {
        struct xfs_mount        *mp = dp->i_mount;
+       struct xfs_inode        *ip;
        xfs_ino_t               lookup_ino;
        xfs_dablk_t             offset;
-       bool                    checked_ftype = false;
        int                     error = 0;
 
        offset = xfs_dir2_db_to_da(mp->m_dir_geo,
@@ -122,9 +93,6 @@ xchk_dir_actor(
 
        if (!strncmp(".", name->name, name->len)) {
                /* If this is "." then check that the inum matches the dir. */
-               if (xfs_has_ftype(mp) && name->type != XFS_DIR3_FT_DIR)
-                       xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
-               checked_ftype = true;
                if (ino != dp->i_ino)
                        xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
        } else if (!strncmp("..", name->name, name->len)) {
@@ -132,9 +100,6 @@ xchk_dir_actor(
                 * If this is ".." in the root inode, check that the inum
                 * matches this dir.
                 */
-               if (xfs_has_ftype(mp) && name->type != XFS_DIR3_FT_DIR)
-                       xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
-               checked_ftype = true;
                if (dp->i_ino == mp->m_sb.sb_rootino && ino != dp->i_ino)
                        xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
        }
@@ -151,14 +116,32 @@ xchk_dir_actor(
                return -ECANCELED;
        }
 
-       /* Verify the file type.  This function absorbs error codes. */
-       if (!checked_ftype) {
-               error = xchk_dir_check_ftype(sc, offset, lookup_ino,
-                               name->type);
-               if (error)
-                       goto out;
+       /*
+        * Grab the inode pointed to by the dirent.  We release the
+        * inode before we cancel the scrub transaction.  Since we're
+        * don't know a priori that releasing the inode won't trigger
+        * eofblocks cleanup (which allocates what would be a nested
+        * transaction), we can't use DONTCACHE here because DONTCACHE
+        * inodes can trigger immediate inactive cleanup of the inode.
+        * Use UNTRUSTED here to check the allocation status of the inode in
+        * the inode btrees.
+        *
+        * If _iget returns -EINVAL or -ENOENT then the child inode number is
+        * garbage and the directory is corrupt.  If the _iget returns
+        * -EFSCORRUPTED or -EFSBADCRC then the child is corrupt which is a
+        *  cross referencing error.  Any other error is an operational error.
+        */
+       error = xfs_iget(mp, sc->tp, ino, XFS_IGET_UNTRUSTED, 0, &ip);
+       if (error == -EINVAL || error == -ENOENT) {
+               error = -EFSCORRUPTED;
+               xchk_fblock_process_error(sc, XFS_DATA_FORK, 0, &error);
+               goto out;
        }
+       if (!xchk_fblock_xref_process_error(sc, XFS_DATA_FORK, offset, &error))
+               goto out;
 
+       xchk_dir_check_ftype(sc, offset, ip, name->type);
+       xfs_irele(ip);
 out:
        if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
                return -ECANCELED;