ocfs2_inode_lock_update(): make sure we don't change the type bits of i_mode

... even if another node has gone insane.  Fail with -ESTALE if it detects
an attempt to change the type bits.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index 8e3a369086dbd56126e050b5ab0daf1035d0ff04..0fbe8bf7190fa48fa5879a0a78afe8e90f5cb9fd 100644 (file)
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -2204,7 +2204,7 @@ static void ocfs2_unpack_timespec(struct timespec64 *spec,
        spec->tv_nsec = packed_time & OCFS2_NSEC_MASK;
 }
 
-static void ocfs2_refresh_inode_from_lvb(struct inode *inode)
+static int ocfs2_refresh_inode_from_lvb(struct inode *inode)
 {
        struct ocfs2_inode_info *oi = OCFS2_I(inode);
        struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres;
@@ -2213,6 +2213,8 @@ static void ocfs2_refresh_inode_from_lvb(struct inode *inode)
        mlog_meta_lvb(0, lockres);
 
        lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
+       if (inode_wrong_type(inode, be16_to_cpu(lvb->lvb_imode)))
+               return -ESTALE;
 
        /* We're safe here without the lockres lock... */
        spin_lock(&oi->ip_lock);
@@ -2240,6 +2242,7 @@ static void ocfs2_refresh_inode_from_lvb(struct inode *inode)
        ocfs2_unpack_timespec(&inode->i_ctime,
                              be64_to_cpu(lvb->lvb_ictime_packed));
        spin_unlock(&oi->ip_lock);
+       return 0;
 }
 
 static inline int ocfs2_meta_lvb_is_trustable(struct inode *inode,
@@ -2342,7 +2345,8 @@ static int ocfs2_inode_lock_update(struct inode *inode,
        if (ocfs2_meta_lvb_is_trustable(inode, lockres)) {
                mlog(0, "Trusting LVB on inode %llu\n",
                     (unsigned long long)oi->ip_blkno);
-               ocfs2_refresh_inode_from_lvb(inode);
+               status = ocfs2_refresh_inode_from_lvb(inode);
+               goto bail_refresh;
        } else {
                /* Boo, we have to go to disk. */
                /* read bh, cast, ocfs2_refresh_inode */
@@ -2352,6 +2356,10 @@ static int ocfs2_inode_lock_update(struct inode *inode,
                        goto bail_refresh;
                }
                fe = (struct ocfs2_dinode *) (*bh)->b_data;
+               if (inode_wrong_type(inode, le16_to_cpu(fe->i_mode))) {
+                       status = -ESTALE;
+                       goto bail_refresh;
+               }
 
                /* This is a good chance to make sure we're not
                 * locking an invalid object.  ocfs2_read_inode_block()