vfs: have do_sys_truncate retry once on an ESTALE error

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

1 files changed, 7 insertions, 1 deletions

diff --git a/fs/open.c b/fs/open.c
index c819bbdab47f..07449b911a4d 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -115,17 +115,23 @@ EXPORT_SYMBOL_GPL(vfs_truncate);
 
 static long do_sys_truncate(const char __user *pathname, loff_t length)
 {
+        unsigned int lookup_flags = LOOKUP_FOLLOW;
         struct path path;
         int error;
 
         if (length < 0) /* sorry, but loff_t says... */
                 return -EINVAL;
 
-        error = user_path(pathname, &path);
+retry:
+        error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path);
         if (!error) {
                 error = vfs_truncate(&path, length);
                 path_put(&path);
         }
+        if (retry_estale(error, lookup_flags)) {
+                lookup_flags |= LOOKUP_REVAL;
+                goto retry;
+        }
         return error;
 }