NFS: check for nfs_refresh_inode() errors in nfs_fhget()
authorNeilBrown <neilb@suse.com>
Mon, 3 Jul 2017 05:27:26 +0000 (15:27 +1000)
committerAnna Schumaker <Anna.Schumaker@Netapp.com>
Thu, 13 Jul 2017 20:00:09 +0000 (16:00 -0400)
If an NFS server returns a filehandle that we have previously
seen, and reports a different type, then nfs_refresh_inode()
will log a warning and return an error.

nfs_fhget() does not check for this error and may return an
inode with a different type than the one that the server
reported.

This is likely to cause confusion, and is one way that
->open_context() could return a directory inode as discussed
in the previous patch.

So if nfs_refresh_inode() returns and error, return that error
from nfs_fhget() to avoid the confusion propagating.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
fs/nfs/inode.c

index 8c465d3c7e057caad1dbf2c692fe054ef7a01177..7e7a894601b9bda412c1addcdaa0ae934ac6d108 100644 (file)
@@ -525,8 +525,14 @@ nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr, st
                nfs_fscache_init_inode(inode);
 
                unlock_new_inode(inode);
-       } else
-               nfs_refresh_inode(inode, fattr);
+       } else {
+               int err = nfs_refresh_inode(inode, fattr);
+               if (err < 0) {
+                       iput(inode);
+                       inode = ERR_PTR(err);
+                       goto out_no_inode;
+               }
+       }
        dprintk("NFS: nfs_fhget(%s/%Lu fh_crc=0x%08x ct=%d)\n",
                inode->i_sb->s_id,
                (unsigned long long)NFS_FILEID(inode),