From 4a3877c4cedd95543f8726b0a98743ed8db0c0fb Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Tue, 3 Apr 2018 01:15:46 -0400
Subject: [PATCH] rpc_pipefs: fix double-dput()
Git-commit: 4a3877c4cedd95543f8726b0a98743ed8db0c0fb
Patch-mainline: v4.17-rc2
References: bsc#1051510

if we ever hit rpc_gssd_dummy_depopulate() dentry passed to
it has refcount equal to 1.  __rpc_rmpipe() drops it and
dput() done after that hits an already freed dentry.

Cc: stable@kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 net/sunrpc/rpc_pipe.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index 0f08934b2cea..c81ef5e6c981 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -1375,6 +1375,7 @@ rpc_gssd_dummy_depopulate(struct dentry *pipe_dentry)
 	struct dentry *clnt_dir = pipe_dentry->d_parent;
 	struct dentry *gssd_dir = clnt_dir->d_parent;
 
+	dget(pipe_dentry);
 	__rpc_rmpipe(d_inode(clnt_dir), pipe_dentry);
 	__rpc_depopulate(clnt_dir, gssd_dummy_info_file, 0, 1);
 	__rpc_depopulate(gssd_dir, gssd_dummy_clnt_dir, 0, 1);
-- 
2.19.0