[PATCH 5.15 058/511] fs: Fix error checking for d_hash_and_lookup()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

5.15-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Wang Ming <machel@vivo.com>

[ Upstream commit 0d5a4f8f775ff990142cdc810a84eae078589d27 ]

The d_hash_and_lookup() function returns error pointers or NULL.
Most incorrect error checks were fixed, but the one in int path_pts()
was forgotten.

Fixes: eedf265aa003 ("devpts: Make each mount of devpts an independent filesystem.")
Signed-off-by: Wang Ming <machel@vivo.com>
Message-Id: <20230713120555.7025-1-machel@vivo.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/namei.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/namei.c b/fs/namei.c
index 885b0e93ee966..ea2785103376e 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2836,7 +2836,7 @@ int path_pts(struct path *path)
 	dput(path->dentry);
 	path->dentry = parent;
 	child = d_hash_and_lookup(parent, &this);
-	if (!child)
+	if (IS_ERR_OR_NULL(child))
 		return -ENOENT;
 
 	path->dentry = child;
-- 
2.40.1