vfs: allow setxattr to retry once on ESTALE errors

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

diff --git a/fs/xattr.c b/fs/xattr.c
index e21c119f4f99d8512208a9c08983dd5f9c25d821..c5e90d2d751fb6fa50200bd98ac2fdbcb26df89e 100644 (file)
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -370,8 +370,9 @@ SYSCALL_DEFINE5(setxattr, const char __user *, pathname,
 {
        struct path path;
        int error;
-
-       error = user_path(pathname, &path);
+       unsigned int lookup_flags = LOOKUP_FOLLOW;
+retry:
+       error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path);
        if (error)
                return error;
        error = mnt_want_write(path.mnt);
@@ -380,6 +381,10 @@ SYSCALL_DEFINE5(setxattr, const char __user *, pathname,
                mnt_drop_write(path.mnt);
        }
        path_put(&path);
+       if (retry_estale(error, lookup_flags)) {
+               lookup_flags |= LOOKUP_REVAL;
+               goto retry;
+       }
        return error;
 }