From: Al Viro <viro@zeniv.linux.org.uk>
Date: Wed, 8 Jun 2016 01:53:51 +0000 (-0400)
Subject: fix a regression in atomic_open()
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=a01e718f7241c53f564402f7acff373eed5bd166;p=linux-beck.git

fix a regression in atomic_open()

open("/foo/no_such_file", O_RDONLY | O_CREAT) on should fail with
EACCES when /foo is not writable; failing with ENOENT is obviously
wrong.  That got broken by a braino introduced when moving the
creat_error logics from atomic_open() to lookup_open().  Easy to
fix, fortunately.

Spotted-by: "Yan, Zheng" <ukernel@gmail.com>
Tested-by: "Yan, Zheng" <ukernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/fs/namei.c b/fs/namei.c
index d7c0cac56d89..28cb1cd8507c 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2995,9 +2995,13 @@ static int atomic_open(struct nameidata *nd, struct dentry *dentry,
 			}
 			if (*opened & FILE_CREATED)
 				fsnotify_create(dir, dentry);
-			path->dentry = dentry;
-			path->mnt = nd->path.mnt;
-			return 1;
+			if (unlikely(d_is_negative(dentry))) {
+				error = -ENOENT;
+			} else {
+				path->dentry = dentry;
+				path->mnt = nd->path.mnt;
+				return 1;
+			}
 		}
 	}
 	dput(dentry);