vfs: fix mknodat to retry on ESTALE errors

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

1 files changed, 7 insertions, 2 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 8f8e41f6eb52..b70c191b7e2b 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3172,12 +3172,13 @@ SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, umode_t, mode,
         struct dentry *dentry;
         struct path path;
         int error;
+        unsigned int lookup_flags = 0;
 
         error = may_mknod(mode);
         if (error)
                 return error;
-
-        dentry = user_path_create(dfd, filename, &path, 0);
+retry:
+        dentry = user_path_create(dfd, filename, &path, lookup_flags);
         if (IS_ERR(dentry))
                 return PTR_ERR(dentry);
 
@@ -3200,6 +3201,10 @@ SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, umode_t, mode,
         }
 out:
         done_path_create(&path, dentry);
+        if (retry_estale(error, lookup_flags)) {
+                lookup_flags |= LOOKUP_REVAL;
+                goto retry;
+        }
         return error;
 }