From: Jeff Layton <jlayton@redhat.com>
Date: Tue, 11 Dec 2012 17:10:12 +0000 (-0500)
Subject: vfs: have chdir retry lookup and call once on ESTALE error
X-Git-Tag: firefly_0821_release~3680^2~1354^2~13
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0291c0a551d5b0856627f2cb294da05f122414a0;p=firefly-linux-kernel-4.4.55.git

vfs: have chdir retry lookup and call once on ESTALE error

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/fs/open.c b/fs/open.c
index a994ccf39b40..402dfcb6720b 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -394,8 +394,9 @@ SYSCALL_DEFINE1(chdir, const char __user *, filename)
 {
 	struct path path;
 	int error;
-
-	error = user_path_dir(filename, &path);
+	unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_DIRECTORY;
+retry:
+	error = user_path_at(AT_FDCWD, filename, lookup_flags, &path);
 	if (error)
 		goto out;
 
@@ -407,6 +408,10 @@ SYSCALL_DEFINE1(chdir, const char __user *, filename)
 
 dput_and_out:
 	path_put(&path);
+	if (retry_estale(error, lookup_flags)) {
+		lookup_flags |= LOOKUP_REVAL;
+		goto retry;
+	}
 out:
 	return error;
 }