From 508c8772760d4ef9c1a044519b564710c3684fc5 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Tue Jan 14 22:09:57 2020 -0500
Subject: [PATCH] fix autofs regression caused by follow_managed() changes 
Git-commit: 508c8772760d4ef9c1a044519b564710c3684fc5
References: bsc#1159271
Patch-mainline: v5.5-rc7

we need to reload ->d_flags after the call of ->d_manage() - the thing
might've been called with dentry still negative and have the damn thing
turned positive while we'd waited.

Fixes: d41efb522e90 "fs/namei.c: pull positivity check into follow_managed()"
Reported-by: Ian Kent <raven@themaw.net>
Tested-by: Ian Kent <raven@themaw.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Goldwyn Rodrigues <rgoldwyn@suse.com>

diff --git a/fs/namei.c b/fs/namei.c
index 204677c..d2720dc 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1232,6 +1232,7 @@ static int follow_managed(struct path *path, struct nameidata *nd)
 			BUG_ON(!path->dentry->d_op);
 			BUG_ON(!path->dentry->d_op->d_manage);
 			ret = path->dentry->d_op->d_manage(path, false);
+			flags = smp_load_acquire(&path->dentry->d_flags);
 			if (ret < 0)
 				break;
 		}