NFS: Really fix put_nfs_open_context()

In nfs_open_revalidate(), if the open_context() call returns an inode that
is not the same as dentry->d_inode, then we will call
put_nfs_open_context() with a valid dentry->d_inode, but without the
context being part of the nfsi->open_files list.

In this case too, we want to just skip the list removal, but we do want to
call the ->close_context() callback in order to close the NFSv4 state.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Jeff Layton <jlayton@redhat.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 702ed096e790..18be041abd23 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -639,6 +639,7 @@ struct nfs_open_context *alloc_nfs_open_context(struct path *path, struct rpc_cr
                 ctx->dir_cookie = 0;
                 nfs_init_lock_context(&ctx->lock_context);
                 ctx->lock_context.open_context = ctx;
+                INIT_LIST_HEAD(&ctx->list);
         }
         return ctx;
 }
@@ -654,14 +655,15 @@ static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
 {
         struct inode *inode = ctx->path.dentry->d_inode;
 
-        if (inode) {
+        if (!list_empty(&ctx->list)) {
                 if (!atomic_dec_and_lock(&ctx->lock_context.count, &inode->i_lock))
                         return;
                 list_del(&ctx->list);
                 spin_unlock(&inode->i_lock);
-                NFS_PROTO(inode)->close_context(ctx, is_sync);
         } else if (!atomic_dec_and_test(&ctx->lock_context.count))
                 return;
+        if (inode != NULL)
+                NFS_PROTO(inode)->close_context(ctx, is_sync);
         if (ctx->cred != NULL)
                 put_rpccred(ctx->cred);
         path_put(&ctx->path);