NFS: Fix an Oops in nfs_d_automount()

[ Upstream commit 35e3b6ae84935d0d7ff76cbdaa83411b0ad5e471 ]

When mounting from a NFSv4 referral, path->dentry can end up being a
negative dentry, so derive the struct nfs_server from the dentry
itself instead.

Fixes: 2b0143b5c986 ("VFS: normal filesystems (and lustre): d_inode() annotations")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c
index 2f336ac..88a23af 100644 (file)
--- a/fs/nfs/namespace.c
+++ b/fs/nfs/namespace.c
@@ -147,7 +147,7 @@ struct vfsmount *nfs_d_automount(struct path *path)
        struct nfs_fs_context *ctx;
        struct fs_context *fc;
        struct vfsmount *mnt = ERR_PTR(-ENOMEM);
-       struct nfs_server *server = NFS_SERVER(d_inode(path->dentry));
+       struct nfs_server *server = NFS_SB(path->dentry->d_sb);
        struct nfs_client *client = server->nfs_client;
        int timeout = READ_ONCE(nfs_mountpoint_expiry_timeout);
        int ret;